Re: Software based SATA RAID-5 expandable arrays?
I have removed the drives from my machine, the problem Im having is that I dont know the order (ports) they go back into the machine. Does anyone know how to determine the order, or how to fix the drive array if the order is not correct? Pinpoint customers who are looking for what you sell. http://searchmarketing.yahoo.com/ - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Software based SATA RAID-5 expandable arrays?
You will learn a lot by building your own system and will allow you to do more with it as far as other services if you want. However, again if you are still having problems with distro selection, configuration and commands, here is another NAS install solution I stumbled on. http://www.openfiler.com They appear to use a Fedora Distro, and remade it into their own. They also use the mdadm packages. I have not played with this, but If I had to chose, I would use this one since I have had more experience with mdadm as oppose to what the freenas is using. Their version of mdadm is not the very latest however. That won't effect you unless you want to be able to grow your RAID. You will need to update it. https://www.openfiler.com/community/forums/viewtopic.php?id=741 Oh, and they do support creating RAID6 arrays http://www.openfiler.com/screenshots/shots/RAID_Mgmt3.png Just giving you more options. Dan. - Original Message - From: Daniel Korstad Sent: Mon, 7/16/2007 7:48am To: Michael Subject: RE: Software based SATA RAID-5 expandable arrays? Something I ran across a year ago. http://www.freenas.org/index.php?option=com_versionsItemid=51 I played with it for a day or so and it look impressive. The project is sill very much alive and they just released a new version a couple days ago. The caveat or reason I did not use this is that I use my Linux box for so many other things, (Web server, Asterisk (voip), Chillispot, VMware Server, Firewall, ... If you go this route, you will pretty much dedicate your box for just a NAS function. The project is an ISO OS you download and install. This greatly simplifies things but it ties you down a bit. After it is built, clients connect to it in server different options you can configure, CIFS (this is windows file sharing or samba), FTP, NFS, RSYNCD, SSHD, Unision, AFP. It also supports hard disk standby time, and advanced power management for your drives. However, if that is all you really want (a NAS) and you are having issues with other Linux distros... This is pretty simple to get one up and running with a NAS. Nice web interface for all the configuration. Other things to consider, I don't think it has RAID6. Or it did not last time I played with it a year ago. And I think the code is different than mdadm. So, you would be looking toward their forums for help if you had issues. Also, here is the manual for you.. http://www.freenas.org/downloads/docs/user-docs/FreeNAS-SUG.pdf Cheers, Dan. - Original Message - From: [EMAIL PROTECTED] on behalf of Daniel Korstad Sent: Fri, 7/13/2007 1:24pm To: big.green.jelly.bean Cc: davidsen ; linux-raid Subject: RE: Software based SATA RAID-5 expandable arrays? I can't speak for SuSe issues but I believe there is some confusion on the packages and command syntax. So hang on, we are going for a ride, step by step... Check and repair are not packages per say. You should have a package called echo. If you run this; echo 1 Should get a 1 echoed back at you. For example; [EMAIL PROTECTED] echo 1 1 Or anything else you want; [EMAIL PROTECTED] echo check check Now all we are doing with this is redirecting with the to another location, /sys/block/md0/md/sync_action The difference between a double and a single is the will append it to the end and the single will replace the contents of the file with the value. For example; I will create a file called foo; [EMAIL PROTECTED] tmp]# vi foo In this file I add two lines of text, foo, than I will write and quit :wq Now I will take a look at the file I just made with my vi editor... [EMAIL PROTECTED] tmp]# cat foo foo foo Great, now I run my echo command to send another value to it. First I use the double to just append; [EMAIL PROTECTED] tmp]# echo foo2 foo Now I take another look at the file; [EMAIL PROTECTED] tmp]# cat foo foo foo foo2 So, I have my first two text lines the third line foo2 appended. Now I do this again but use just the single to replace the file with a value. [EMAIL PROTECTED] tmp]# echo foo3 foo Than I look at it again; [EMAIL PROTECTED] tmp]# cat foo foo3 Ahh, all the other lines are gone and now I just have foo3. So, replaces and appends. How does this affect your /sys/block/md0/md/sync_action file? As it turns out, it does not matter. Think of the proc and sys (/proc and /sys) as psuedo file system is a real time, memory resident file system that tracks the processes running on your machine and the state of your system. So first lets go to /sys/block/ Than I will list its contents; [EMAIL PROTECTED] ~]# cd /sys/block/ [EMAIL PROTECTED] block]# ls dm-0 dm-3 hda md1 ram0 ram11 ram14 ram3 ram6 ram9 sdc sdf sdi dm-1 dm-4 hdc md2 ram1 ram12 ram15 ram4 ram7 sda sdd sdg dm-2 dm-5 md0 md3 ram10 ram13 ram2 ram5 ram8 sdb sde sdh This will be different for you since your system will have different hardware
Re: Software based SATA RAID-5 expandable arrays?
Due too the nature of the data I am storing RAID-6 is not really worth the extra safety and security, though it would be if I could get another 6 drives. Maybe then I can convert my RAID 5 into a RAID 6. As for openfiler, it is a great, simple package that provides all the features I need except that they dont include the latest kernel. That means my motherboard isnt supported. (frown). I have installed Fedora, after all the hastle of SuSe, and am currently setting that up so that it can be my main OS. It seems great, just some of the GUI based Admin tools are cryptic in their function. I have Mirrored my boot drive, which means I have to check to see if the second drive can be booted from. This is my todo list (though it does fail to mention SMART!), the times on the crontab have to be corrected. -- SAMBA http://www.redhatmagazine.com/2007/06/26/how-to-build-a-dirt-easy-home-nas-server-using-samba/ Repair http://www.issociate.de/board/post/391115/Observations_of_a_failing_disk.html http://www.issociate.de/board/post/443666/how_to_deal_with_continuously_getting_more_errors?.html Crontab (Weekly Repair Schedule) http://www.unixgeeks.org/security/newbie/unix/cron-1.html http://www.ss64.com/bash/crontab.html\ crontab -e 30 3 * * Mon echo check /sys/block/md3/md/sync_action 30 4 * * Mon echo check /sys/block/md0/md/sync_action 30 4 * * Mon echo check /sys/block/md1/md/sync_action 30 4 * * Mon echo check /sys/block/md2/md/sync_action Check Boot Info on Mirrored Drive After you go through the install and have a bootable OS that is running on mdadm RAID, I would test it to make sure grub was installed correctly to both the physical drives. If grub is not installed to both drives, and you lose one drive down the road and if that one was the one with grub, you will have a system that will not boot even though it has a second drive with a copy of all the files. If this were to happen, you can recover by booting with a bootable linux CD or recover disk and manually installing grub too. For example say you only had grub installed to hda and it failed, boot with a live linux cd and type (assuming /dev/hdd is the surviving second drive); grub device (hd0) /dev/hdd root (hd0,0) setup (hd0) quit System Report Email Mutt http://www.mutt.org/ http://linux.die.net/man/8/auditd.conf - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: Michael [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Monday, July 16, 2007 10:23:23 AM Subject: RE: Software based SATA RAID-5 expandable arrays? You will learn a lot by building your own system and will allow you to do more with it as far as other services if you want. However, again if you are still having problems with distro selection, configuration and commands, here is another NAS install solution I stumbled on. http://www.openfiler.com They appear to use a Fedora Distro, and remade it into their own. They also use the mdadm packages. I have not played with this, but If I had to chose, I would use this one since I have had more experience with mdadm as oppose to what the freenas is using. Their version of mdadm is not the very latest however. That won't effect you unless you want to be able to grow your RAID. You will need to update it. https://www.openfiler.com/community/forums/viewtopic.php?id=741 Oh, and they do support creating RAID6 arrays http://www.openfiler.com/screenshots/shots/RAID_Mgmt3.png Just giving you more options. Dan. - Original Message - From: Daniel Korstad Sent: Mon, 7/16/2007 7:48am To: Michael Subject: RE: Software based SATA RAID-5 expandable arrays? Something I ran across a year ago. http://www.freenas.org/index.php?option=com_versionsItemid=51 I played with it for a day or so and it look impressive. The project is sill very much alive and they just released a new version a couple days ago. The caveat or reason I did not use this is that I use my Linux box for so many other things, (Web server, Asterisk (voip), Chillispot, VMware Server, Firewall, ... If you go this route, you will pretty much dedicate your box for just a NAS function. The project is an ISO OS you download and install. This greatly simplifies things but it ties you down a bit. After it is built, clients connect to it in server different options you can configure, CIFS (this is windows file sharing or samba), FTP, NFS, RSYNCD, SSHD, Unision, AFP. It also supports hard disk standby time, and advanced power management for your drives. However, if that is all you really want (a NAS) and you are having issues with other Linux distros... This is pretty simple to get one up and running with a NAS. Nice web interface for all the configuration. Other things to consider, I don't think it has RAID6. Or it did not last time I played with it a year ago. And I think the code is different than mdadm. So, you would be looking toward
RE: Software based SATA RAID-5 expandable arrays?
Don't forget the or either one will do... crontab -e 30 3 * * Mon echo check /sys/block/md3/md/sync_action 30 4 * * Mon echo check /sys/block/md0/md/sync_action 30 4 * * Mon echo check /sys/block/md1/md/sync_action 30 4 * * Mon echo check /sys/block/md2/md/sync_action - Original Message - From: Michael Sent: Mon, 7/16/2007 12:34pm To: Daniel Korstad Cc: linux-raid@vger.kernel.org Subject: Re: Software based SATA RAID-5 expandable arrays? Due too the nature of the data I am storing RAID-6 is not really worth the extra safety and security, though it would be if I could get another 6 drives. Maybe then I can convert my RAID 5 into a RAID 6. As for openfiler, it is a great, simple package that provides all the features I need except that they dont include the latest kernel. That means my motherboard isnt supported. (frown). I have installed Fedora, after all the hastle of SuSe, and am currently setting that up so that it can be my main OS. It seems great, just some of the GUI based Admin tools are cryptic in their function. I have Mirrored my boot drive, which means I have to check to see if the second drive can be booted from. This is my todo list (though it does fail to mention SMART!), the times on the crontab have to be corrected. -- SAMBA http://www.redhatmagazine.com/2007/06/26/how-to-build-a-dirt-easy-home-nas-server-using-samba/ Repair http://www.issociate.de/board/post/391115/Observations_of_a_failing_disk.html http://www.issociate.de/board/post/443666/how_to_deal_with_continuously_getting_more_errors?.html Crontab (Weekly Repair Schedule) http://www.unixgeeks.org/security/newbie/unix/cron-1.html http://www.ss64.com/bash/crontab.html\ crontab -e 30 3 * * Mon echo check /sys/block/md3/md/sync_action 30 4 * * Mon echo check /sys/block/md0/md/sync_action 30 4 * * Mon echo check /sys/block/md1/md/sync_action 30 4 * * Mon echo check /sys/block/md2/md/sync_action Check Boot Info on Mirrored Drive After you go through the install and have a bootable OS that is running on mdadm RAID, I would test it to make sure grub was installed correctly to both the physical drives. If grub is not installed to both drives, and you lose one drive down the road and if that one was the one with grub, you will have a system that will not boot even though it has a second drive with a copy of all the files. If this were to happen, you can recover by booting with a bootable linux CD or recover disk and manually installing grub too. For example say you only had grub installed to hda and it failed, boot with a live linux cd and type (assuming /dev/hdd is the surviving second drive); grub device (hd0) /dev/hdd root (hd0,0) setup (hd0) quit System Report Email Mutt http://www.mutt.org/ http://linux.die.net/man/8/auditd.conf - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: Michael [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Monday, July 16, 2007 10:23:23 AM Subject: RE: Software based SATA RAID-5 expandable arrays? You will learn a lot by building your own system and will allow you to do more with it as far as other services if you want. However, again if you are still having problems with distro selection, configuration and commands, here is another NAS install solution I stumbled on. http://www.openfiler.com They appear to use a Fedora Distro, and remade it into their own. They also use the mdadm packages. I have not played with this, but If I had to chose, I would use this one since I have had more experience with mdadm as oppose to what the freenas is using. Their version of mdadm is not the very latest however. That won't effect you unless you want to be able to grow your RAID. You will need to update it. https://www.openfiler.com/community/forums/viewtopic.php?id=741 Oh, and they do support creating RAID6 arrays http://www.openfiler.com/screenshots/shots/RAID_Mgmt3.png Just giving you more options. Dan. - Original Message - From: Daniel Korstad Sent: Mon, 7/16/2007 7:48am To: Michael Subject: RE: Software based SATA RAID-5 expandable arrays? Something I ran across a year ago. http://www.freenas.org/index.php?option=com_versionsItemid=51 I played with it for a day or so and it look impressive. The project is sill very much alive and they just released a new version a couple days ago. The caveat or reason I did not use this is that I use my Linux box for so many other things, (Web server, Asterisk (voip), Chillispot, VMware Server, Firewall, ... If you go this route, you will pretty much dedicate your box for just a NAS function. The project is an ISO OS you download and install. This greatly simplifies things but it ties you down a bit. After it is built, clients connect to it in server different options you can configure, CIFS (this is windows file sharing or samba), FTP, NFS, RSYNCD, SSHD, Unision, AFP. It also supports hard disk standby time
Re: Software based SATA RAID-5 expandable arrays?
Daniel Korstad wrote: That was true up to kernel 2.6.21 and 2.6 mdadm where support for RAID 6 reshape arrived. I have reshaped (added additional drives) to my RAID 6 twice now with no problems in the past few months. You mentioned that as the only disadvantage. There are other things to consider. The overhead for parity of course. You can't have a RAID 6 with only three drives unless you build it with a missing drive and run degraded. Also (my opinion) it might not worth the overhead with only 4 drives, unless you plan to reshape (add drives) down the road. When you have an array with several drives, than it is more advantages as the percentage of disk space lost to parity goes down [((2/N)*100) where N is the number of drives in the array] so your storage efficiency increases ((Number of Drives -2)/Number of Drives). And with more drives the statistics of getting hit with a bit error after you lose a drive and you are trying to rebuild increases. Also, there is a very slight performance drop for write speeds on RAID6 since you are calculating p and q parity. I would expect (and see) a fairly substantial drop in write performance. With RAID-5 only the parity needs to be read on a data change, and the old data chunk. Then several XORs are done and the new data and new parity written. With RAID-6, I believe that all the data in the stripe need be read for calculating the q parity. But for what I use my system for, family digital photos, file storage and media server I mostly read data and not bothered with slight performance hit in write. I have been using RAID6 with 10 disk for over a year and it has saved me at least once. As far as converting the RAID6 to RAID5 or RAID4... Never had a need to do this, but no probably not. Agree, for many things the write performance is not an issue, while the reliability is. Backups are still desirable, of course. -- bill davidsen [EMAIL PROTECTED] CTO TMR Associates, Inc Doing interesting things with small computers since 1979 - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Software based SATA RAID-5 expandable arrays?
To run it manually; echo check /sys/block/md0/md/sync_action than you can check the status with; cat /proc/mdstat Or to continually watch it, if you want (kind of boring though :) ) watch cat /proc/mdstat This will refresh ever 2sec. In my original email I suggested to use a crontab so you don't need to remember to do this every once in a while. Run (I did this in root); crontab -e This will allow you to edit you crontab. Now past this command in there; 30 2 * * Mon echo check /sys/block/md0/md/sync_action If you want you can add comments, I like to comment my stuff since I have lots of stuff in mine, just make sure you have '#' in the front of the lines so your system knows it is just a comment and not a command it should run; #check for bad blocks once a week (every Mon at 2:30am) #if bad blocks are found, they are corrected from parity information After you have put this in your crontab, write and quit with this command; :wq It should come back with this; [EMAIL PROTECTED] ~]# crontab -e crontab: installing new crontab Now you can look at your cron table (without editing) with this; crontab -l It should return something like this, depending if you added comments or how you scheduled your command; #check for bad blocks once a week (every Mon at 2:30am) #if bad blocks are found, they are corrected from parity information 30 2 * * Mon echo check /sys/block/md0/md/sync_action For more info on crontab and syntax for times (I just did a google and grabbed the first couple links...); http://www.tech-geeks.org/contrib/mdrone/croncrontab-howto.htm http://ubuntuforums.org/showthread.php?t=102626highlight=cron Cheers, Dan. -Original Message- From: Michael [mailto:[EMAIL PROTECTED] Sent: Thursday, July 12, 2007 5:43 PM To: Bill Davidsen; Daniel Korstad Cc: linux-raid@vger.kernel.org Subject: Re: Software based SATA RAID-5 expandable arrays? SuSe uses its own version of cron which is different then everything else I have seen, and the documentation is horrible. However they provide a wonderfull xwindows utility that helps set them up... the problem Im having is figuring out what to run. When I try to run /sys/block/md0/md/sync_action under a prompt it shoots out a permission denied even though I am SU or logged in under Root. Very annoying. You mention Check vrs Repair... which brings me too my last issue on setting up this machine. How do you send an email when Check, SMART, and when a RAID drive fails? How do you auto repair if the Check fails? These are the last things I need to do for my Linux Server to work right... after I get all of this done, I will change the boot to goto the command prompt and not XWindows, and I will leave it in the corner of my room hopefully not to be used for as long as possible. - Original Message From: Bill Davidsen [EMAIL PROTECTED] To: Daniel Korstad [EMAIL PROTECTED] Cc: Michael [EMAIL PROTECTED]; linux-raid@vger.kernel.org Sent: Wednesday, July 11, 2007 10:21:42 AM Subject: Re: Software based SATA RAID-5 expandable arrays? Daniel Korstad wrote: You have lots of options. This will be a lengthy response and will give just some ideas for just some of the options... Just a few thoughts below interspersed with your comments. For my server, I had started out with a single drive. I later migrated to migrate to a RAID 1 mirror (after having to deal with reinstalls after drive failures I wised up). Since I already had an OS that I wanted to keep, my RAID-1 setup was a bit more involved. I following this migration to get me there; http://wiki.clug.org.za/wiki/RAID-1_in_a_hurry_with_grub_and_mdadm Since you are starting from scratch, it should be easier for you. Most distros will have an installer that will guide you though the process. When you get to hard drive partitioning, look for an advance option or review and modify partition layout option or something similar otherwise it might just make a guess of what you want and that would not be RAID. In this advance partition setup, you will be able to create your RAID. First you make equal size partitions on both physical drives. For example, first carve out 100M partition on each of the two physical OS drives, than make a RAID 1 md0 with each of this partitions and than make this your /boot. Do this again for other partitions you want to have RAIDed. You can do this for /boot, /var, /home, /tmp, /usr. This is can be nice to have a separations incase a user fills /home/foo with crap and this will not effect other parts of the OS, or if mail spool fills up, it will not hang the OS. Only problem it determining how big to make them during the install. At a minimum, I would do three partitions; /boot, swap, and / This means all the others (/var, /home, /tmp, /usr) are in the / partition but this way you don't have to worry about sizing them all correctly. For the simplest setup, I would do RAID 1
Re: Software based SATA RAID-5 expandable arrays?
Michael wrote: RESPONSE I had everything working, but it is evident that when I installed SuSe the first time check and repair where not included in the package:( I did not use the I used , as was incorrectly stated in many documentations I set up. Doesn't matter, either will work and most people just use The thing that made me suspect check and repair wasn't part of sues was the failure of check or repair typed at the command prompt to respond in any kind other then a response that stated their was no command. In addition man check and man repair was also missing. One more time, check and repair are not commands, they are character strings! You are using the echo command to write those strings into the control interface in the sysfs area. If you type exactly what people have sent you that will work. BROKEN! I did an auto update of the SuSe machine, which ended up replacing the kernel. They added the new entries to the boot choices but the mount information was not transfered. SuSe also deleted the original kernel boot setup. When suse looked at the drives individually they found that none of them was recognizable. Therefor when I woke up this morning and rebooted the machine after the update, I received the errors and then dumps me to a basic prompt with limited ability to do anything. I know I need to manually remount the drives, but its going to be a challenge since I did not do this in the past. The answer to this question is that I either have to change distro's (which I am tempted to do) or fix the current distro. Please do not bother providing any solutions for I simply have to RTFM (which I haven't had time to do). I think I am going to reset up my machines. The first two drives with identical boot partitions, yet not mirror them. I can then manually run a tree copy that would update my second drive as I grow the system, and after successfull and needed updates. This would then allow me a fall back after any updates, and with simply swapping SATA drive cables from the first boot drive too the second. I am assuming this will work. I then can RAID-6 (or 5) in the setup, recopy my files (yes I haven't deleted them because I am not confident in my ability with Linux yet.). Hopefully I will just simply remount these 4 drives because there a simple raid 5 array. SUSE's COMPLETE FAILURES This frustration with SuSe, the lack of a simple reliable update utility and the failures I experience has discouraged me from using SuSe at all. Its got some amazing tools that help me from constantly looking up documentation, posting to forums, or going to IRC, but the unreliable upgrade process is a deal breaker for me. Its simply to much work to manually update everything. This project had a simple goal, which was to provide an easy and cheap solution to an unlimited NAS service. SUPPORT In addition, SuSe's IRC help channel is among the worst I have encountered. The level of support is often very good, but the level of harassment, flames and simple childish behavior overcomes almost any attempt at providing any level of support. I have no problem giving back to the community when I learn enough to do so, but I will not be mocked for my inability to understand a new and very in depth system. In fact, I tend to goto the wonderful gentoo irc for my answers. The IRC is amazing, the people patient and encouraging, the level of knowledge is the best I have experienced. This resource, outside the original incident, has been an amazing resource. I feel highly confident asking questions about RAID here, because I know you guys are actually RUNNING systems that I am attempting to do. - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: big.green.jelly.bean [EMAIL PROTECTED] Cc: davidsen [EMAIL PROTECTED]; linux-raid linux-raid@vger.kernel.org Sent: Friday, July 13, 2007 11:22:45 AM Subject: RE: Software based SATA RAID-5 expandable arrays? To run it manually; echo check /sys/block/md0/md/sync_action than you can check the status with; cat /proc/mdstat Or to continually watch it, if you want (kind of boring though :) ) watch cat /proc/mdstat This will refresh ever 2sec. In my original email I suggested to use a crontab so you don't need to remember to do this every once in a while. Run (I did this in root); crontab -e This will allow you to edit you crontab. Now past this command in there; 30 2 * * Mon echo check /sys/block/md0/md/sync_action If you want you can add comments, I like to comment my stuff since I have lots of stuff in mine, just make sure you have '#' in the front of the lines so your system knows it is just a comment and not a command it should run; #check for bad blocks once a week (every Mon at 2:30am) #if bad blocks are found, they are corrected from parity information After you have put this in your crontab, write and quit with this command; :wq It should come back with this; [EMAIL PROTECTED] ~]# crontab -e
RE: Software based SATA RAID-5 expandable arrays?
into a router; echo 1 /proc/sys/net/ipv4/ip_forward As for SuSe updating your kernel, removing your original one and breaking your box by dropping you to a limited shell on boot up.. I can't help you much there. I don't have SuSe but as I understand, they are a good distro. In my current distro, Fedora, you can tell the update manager to not update the kernel. Also in Fedora, it will keep your old kernel by default so if there was an issue, you can select to go back to it in the grub boot up menu. I believe Ubuntu is similar. I bet you could configure SuSe to do the same. I hope that clears up some confusion and good luck. Dan. -Original Message- From: Michael [mailto:[EMAIL PROTECTED] Sent: Friday, July 13, 2007 11:48 AM To: Daniel Korstad Cc: davidsen; linux-raid Subject: Re: Software based SATA RAID-5 expandable arrays? RESPONSE I had everything working, but it is evident that when I installed SuSe the first time check and repair where not included in the package:( I did not use the I used , as was incorrectly stated in many documentations I set up. The thing that made me suspect check and repair wasn't part of sues was the failure of check or repair typed at the command prompt to respond in any kind other then a response that stated their was no command. In addition man check and man repair was also missing. BROKEN! I did an auto update of the SuSe machine, which ended up replacing the kernel. They added the new entries to the boot choices but the mount information was not transfered. SuSe also deleted the original kernel boot setup. When suse looked at the drives individually they found that none of them was recognizable. Therefor when I woke up this morning and rebooted the machine after the update, I received the errors and then dumps me to a basic prompt with limited ability to do anything. I know I need to manually remount the drives, but its going to be a challenge since I did not do this in the past. The answer to this question is that I either have to change distro's (which I am tempted to do) or fix the current distro. Please do not bother providing any solutions for I simply have to RTFM (which I haven't had time to do). I think I am going to reset up my machines. The first two drives with identical boot partitions, yet not mirror them. I can then manually run a tree copy that would update my second drive as I grow the system, and after successfull and needed updates. This would then allow me a fall back after any updates, and with simply swapping SATA drive cables from the first boot drive too the second. I am assuming this will work. I then can RAID-6 (or 5) in the setup, recopy my files (yes I haven't deleted them because I am not confident in my ability with Linux yet.). Hopefully I will just simply remount these 4 drives because there a simple raid 5 array. SUSE's COMPLETE FAILURES This frustration with SuSe, the lack of a simple reliable update utility and the failures I experience has discouraged me from using SuSe at all. Its got some amazing tools that help me from constantly looking up documentation, posting to forums, or going to IRC, but the unreliable upgrade process is a deal breaker for me. Its simply to much work to manually update everything. This project had a simple goal, which was to provide an easy and cheap solution to an unlimited NAS service. SUPPORT In addition, SuSe's IRC help channel is among the worst I have encountered. The level of support is often very good, but the level of harassment, flames and simple childish behavior overcomes almost any attempt at providing any level of support. I have no problem giving back to the community when I learn enough to do so, but I will not be mocked for my inability to understand a new and very in depth system. In fact, I tend to goto the wonderful gentoo irc for my answers. The IRC is amazing, the people patient and encouraging, the level of knowledge is the best I have experienced. This resource, outside the original incident, has been an amazing resource. I feel highly confident asking questions about RAID here, because I know you guys are actually RUNNING systems that I am attempting to do. - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: big.green.jelly.bean [EMAIL PROTECTED] Cc: davidsen [EMAIL PROTECTED]; linux-raid linux-raid@vger.kernel.org Sent: Friday, July 13, 2007 11:22:45 AM Subject: RE: Software based SATA RAID-5 expandable arrays? To run it manually; echo check /sys/block/md0/md/sync_action than you can check the status with; cat /proc/mdstat Or to continually watch it, if you want (kind of boring though :) ) watch cat /proc/mdstat This will refresh ever 2sec. In my original email I suggested to use a crontab so you don't need to remember to do this every once in a while. Run (I did this in root); crontab -e This will allow you to edit you crontab. Now past this command in there; 30 2 * * Mon echo check /sys
Re: Software based SATA RAID-5 expandable arrays?
SuSe uses its own version of cron which is different then everything else I have seen, and the documentation is horrible. However they provide a wonderfull xwindows utility that helps set them up... the problem Im having is figuring out what to run. When I try to run /sys/block/md0/md/sync_action under a prompt it shoots out a permission denied even though I am SU or logged in under Root. Very annoying. You mention Check vrs Repair... which brings me too my last issue on setting up this machine. How do you send an email when Check, SMART, and when a RAID drive fails? How do you auto repair if the Check fails? These are the last things I need to do for my Linux Server to work right... after I get all of this done, I will change the boot to goto the command prompt and not XWindows, and I will leave it in the corner of my room hopefully not to be used for as long as possible. - Original Message From: Bill Davidsen [EMAIL PROTECTED] To: Daniel Korstad [EMAIL PROTECTED] Cc: Michael [EMAIL PROTECTED]; linux-raid@vger.kernel.org Sent: Wednesday, July 11, 2007 10:21:42 AM Subject: Re: Software based SATA RAID-5 expandable arrays? Daniel Korstad wrote: You have lots of options. This will be a lengthy response and will give just some ideas for just some of the options... Just a few thoughts below interspersed with your comments. For my server, I had started out with a single drive. I later migrated to migrate to a RAID 1 mirror (after having to deal with reinstalls after drive failures I wised up). Since I already had an OS that I wanted to keep, my RAID-1 setup was a bit more involved. I following this migration to get me there; http://wiki.clug.org.za/wiki/RAID-1_in_a_hurry_with_grub_and_mdadm Since you are starting from scratch, it should be easier for you. Most distros will have an installer that will guide you though the process. When you get to hard drive partitioning, look for an advance option or review and modify partition layout option or something similar otherwise it might just make a guess of what you want and that would not be RAID. In this advance partition setup, you will be able to create your RAID. First you make equal size partitions on both physical drives. For example, first carve out 100M partition on each of the two physical OS drives, than make a RAID 1 md0 with each of this partitions and than make this your /boot. Do this again for other partitions you want to have RAIDed. You can do this for /boot, /var, /home, /tmp, /usr. This is can be nice to have a separations incase a user fills /home/foo with crap and this will not effect other parts of the OS, or if mail spool fills up, it will not hang the OS. Only problem it determining how big to make them during the install. At a minimum, I would do three partitions; /boot, swap, and / This means all the others (/var, /home, /tmp, /usr) are in the / partition but this way you don't have to worry about sizing them all correctly. For the simplest setup, I would do RAID 1 for /boot (md0), swap (md1), and / (md2) (Alternatively, your could make a swap file in / and not have a swap partition, tons of options...) Do you need to RAID your swap? Well, I would RAID it or make a swap file within a RAID partition. If you don't and your system is using swap and you lose a drive that has swap information/partition on it, you might have issues depending on how important that information in the failed drive was. You systems might hang. Note that RAID-10 generally performs better than mirroring, particularly when more than a few drives are involved. This can have performance implications for swap, when large i/o pushes program pages out of memory. The other side of that coin is that recovery CDs don't seem to know how to use RAID-10 swap, which might be an issue on some systems. After you go through the install and have a bootable OS that is running on mdadm RAID, I would test it to make sure grub was installed correctly to both the physical drives. If grub is not installed to both drives, and you lose one drive down the road and if that one was the one with grub, you will have a system that will not boot even though it has a second drive with a copy of all the files. If this were to happen, you can recover by booting with a bootable linux CD or recover disk and manually installing grub too. For example say you only had grub installed to hda and it failed, boot with a live linux cd and type (assuming /dev/hdd is the surviving second drive); grub device (hd0) /dev/hdd root (hd0,0) setup (hd0) quit You say you are using two 500G drives for the OS. You don't necessary have to use all the space for the OS. You can make your partitions and take the left over space and throw it into a logical volume. This logical volume would not be fault tolerant, but would be the sum of the left over capacity from
Re: Software based SATA RAID-5 expandable arrays?
Michael wrote: SuSe uses its own version of cron which is different then everything else I have seen, and the documentation is horrible. However they provide a wonderfull xwindows utility that helps set them up... the problem Im having is figuring out what to run. When I try to run /sys/block/md0/md/sync_action under a prompt it shoots out a permission denied even though I am SU or logged in under Root. Very annoying. You mention Check vrs Repair... which brings me too my last issue on setting up this machine. How do you send an email when Check, SMART, and when a RAID drive fails? How do you auto repair if the Check fails? The command is echo! As in echo check /sys/block/md0/md/sync_action Read the man page on what happens if you echo repair instead of check there, which might be more what you want to do. Only you can decide. These are the last things I need to do for my Linux Server to work right... after I get all of this done, I will change the boot to goto the command prompt and not XWindows, and I will leave it in the corner of my room hopefully not to be used for as long as possible. - Original Message From: Bill Davidsen [EMAIL PROTECTED] To: Daniel Korstad [EMAIL PROTECTED] Cc: Michael [EMAIL PROTECTED]; linux-raid@vger.kernel.org Sent: Wednesday, July 11, 2007 10:21:42 AM Subject: Re: Software based SATA RAID-5 expandable arrays? Daniel Korstad wrote: You have lots of options. This will be a lengthy response and will give just some ideas for just some of the options... Just a few thoughts below interspersed with your comments. For my server, I had started out with a single drive. I later migrated to migrate to a RAID 1 mirror (after having to deal with reinstalls after drive failures I wised up). Since I already had an OS that I wanted to keep, my RAID-1 setup was a bit more involved. I following this migration to get me there; http://wiki.clug.org.za/wiki/RAID-1_in_a_hurry_with_grub_and_mdadm Since you are starting from scratch, it should be easier for you. Most distros will have an installer that will guide you though the process. When you get to hard drive partitioning, look for an advance option or review and modify partition layout option or something similar otherwise it might just make a guess of what you want and that would not be RAID. In this advance partition setup, you will be able to create your RAID. First you make equal size partitions on both physical drives. For example, first carve out 100M partition on each of the two physical OS drives, than make a RAID 1 md0 with each of this partitions and than make this your /boot. Do this again for other partitions you want to have RAIDed. You can do this for /boot, /var, /home, /tmp, /usr. This is can be nice to have a separations incase a user fills /home/foo with crap and this will not effect other parts of the OS, or if mail spool fills up, it will not hang the OS. Only problem it determining how big to make them during the install. At a minimum, I would do three partitions; /boot, swap, and / This means all the others (/var, /home, /tmp, /usr) are in the / partition but this way you don't have to worry about sizing them all correctly. For the simplest setup, I would do RAID 1 for /boot (md0), swap (md1), and / (md2) (Alternatively, your could make a swap file in / and not have a swap partition, tons of options...) Do you need to RAID your swap? Well, I would RAID it or make a swap file within a RAID partition. If you don't and your system is using swap and you lose a drive that has swap information/partition on it, you might have issues depending on how important that information in the failed drive was. You systems might hang. Note that RAID-10 generally performs better than mirroring, particularly when more than a few drives are involved. This can have performance implications for swap, when large i/o pushes program pages out of memory. The other side of that coin is that recovery CDs don't seem to know how to use RAID-10 swap, which might be an issue on some systems. After you go through the install and have a bootable OS that is running on mdadm RAID, I would test it to make sure grub was installed correctly to both the physical drives. If grub is not installed to both drives, and you lose one drive down the road and if that one was the one with grub, you will have a system that will not boot even though it has a second drive with a copy of all the files. If this were to happen, you can recover by booting with a bootable linux CD or recover disk and manually installing grub too. For example say you only had grub installed to hda and it failed, boot with a live linux cd and type (assuming /dev/hdd is the surviving second drive); grub device (hd0) /dev/hdd root (hd0,0) setup (hd0) quit You say you are using two 500G drives for the OS. You don't necessary have to use all the space for the OS. You can
RE: Software based SATA RAID-5 expandable arrays?
That was true up to kernel 2.6.21 and 2.6 mdadm where support for RAID 6 reshape arrived. I have reshaped (added additional drives) to my RAID 6 twice now with no problems in the past few months. You mentioned that as the only disadvantage. There are other things to consider. The overhead for parity of course. You can't have a RAID 6 with only three drives unless you build it with a missing drive and run degraded. Also (my opinion) it might not worth the overhead with only 4 drives, unless you plan to reshape (add drives) down the road. When you have an array with several drives, than it is more advantages as the percentage of disk space lost to parity goes down [((2/N)*100) where N is the number of drives in the array] so your storage efficiency increases ((Number of Drives -2)/Number of Drives). And with more drives the statistics of getting hit with a bit error after you lose a drive and you are trying to rebuild increases. Also, there is a very slight performance drop for write speeds on RAID6 since you are calculating p and q parity. But for what I use my system for, family digital photos, file storage and media server I mostly read data and not bothered with slight performance hit in write. I have been using RAID6 with 10 disk for over a year and it has saved me at least once. As far as converting the RAID6 to RAID5 or RAID4... Never had a need to do this, but no probably not. Dan. - Inline Message Follows - To: Daniel Korstad ; Michael Cc: linux-raid@vger.kernel.org From: jahammonds prost Subject: Re: Software based SATA RAID-5 expandable arrays? Why do I use RAID6? For the extra redundancy I've been thinking about RAID6 too, having been bitten a couple of times the only disadvantage that I can see at the moment is that you can't convert and grow it... ie... I can't convert from a 4 drive RAID5 array to a 5 drive RAID6 one when I add an additional drive... I also don't think that you can grow a RAID6 array at the moment - I'd want to add additional drives over a few months as they come on sale Or am I wrong on both counts? Graham - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
Daniel Korstad wrote: You have lots of options. This will be a lengthy response and will give just some ideas for just some of the options... Just a few thoughts below interspersed with your comments. For my server, I had started out with a single drive. I later migrated to migrate to a RAID 1 mirror (after having to deal with reinstalls after drive failures I wised up). Since I already had an OS that I wanted to keep, my RAID-1 setup was a bit more involved. I following this migration to get me there; http://wiki.clug.org.za/wiki/RAID-1_in_a_hurry_with_grub_and_mdadm Since you are starting from scratch, it should be easier for you. Most distros will have an installer that will guide you though the process. When you get to hard drive partitioning, look for an advance option or review and modify partition layout option or something similar otherwise it might just make a guess of what you want and that would not be RAID. In this advance partition setup, you will be able to create your RAID. First you make equal size partitions on both physical drives. For example, first carve out 100M partition on each of the two physical OS drives, than make a RAID 1 md0 with each of this partitions and than make this your /boot. Do this again for other partitions you want to have RAIDed. You can do this for /boot, /var, /home, /tmp, /usr. This is can be nice to have a separations incase a user fills /home/foo with crap and this will not effect other parts of the OS, or if mail spool fills up, it will not hang the OS. Only problem it determining how big to make them during the install. At a minimum, I would do three partitions; /boot, swap, and / This means all the others (/var, /home, /tmp, /usr) are in the / partition but this way you don't have to worry about sizing them all correctly. For the simplest setup, I would do RAID 1 for /boot (md0), swap (md1), and / (md2) (Alternatively, your could make a swap file in / and not have a swap partition, tons of options...) Do you need to RAID your swap? Well, I would RAID it or make a swap file within a RAID partition. If you don't and your system is using swap and you lose a drive that has swap information/partition on it, you might have issues depending on how important that information in the failed drive was. You systems might hang. Note that RAID-10 generally performs better than mirroring, particularly when more than a few drives are involved. This can have performance implications for swap, when large i/o pushes program pages out of memory. The other side of that coin is that recovery CDs don't seem to know how to use RAID-10 swap, which might be an issue on some systems. After you go through the install and have a bootable OS that is running on mdadm RAID, I would test it to make sure grub was installed correctly to both the physical drives. If grub is not installed to both drives, and you lose one drive down the road and if that one was the one with grub, you will have a system that will not boot even though it has a second drive with a copy of all the files. If this were to happen, you can recover by booting with a bootable linux CD or recover disk and manually installing grub too. For example say you only had grub installed to hda and it failed, boot with a live linux cd and type (assuming /dev/hdd is the surviving second drive); grub device (hd0) /dev/hdd root (hd0,0) setup (hd0) quit You say you are using two 500G drives for the OS. You don't necessary have to use all the space for the OS. You can make your partitions and take the left over space and throw it into a logical volume. This logical volume would not be fault tolerant, but would be the sum of the left over capacity from both drives. For example, you use 100M for /boot and 200G for / and 2G for swap. Take the rest and make a standard ext3 partition for the remaining space on both drives and put them in a logical volume giving over 500G to play with for non critical crap. Why do I use RAID6? For the extra redundancy and I have 10 drives in my arrary. I have been an advocate for RAID 6, especially with the every increasing drive capacity and the number of drives in the array is above say six; http://www.intel.com/technology/magazine/computing/RAID-6-0505.htm Other configurations will perform better for writes, know your i/o performance requirements. http://storageadvisors.adaptec.com/2005/10/13/raid-5-pining-for-the-fjords/ ...for using RAID-6, the single biggest reason is based on the chance of drive errors during an array rebuild after just a single drive failure. Rebuilding the data on a failed drive requires that all the other data on the other drives be pristine and error free. If there is a single error in a single sector, then the data for the corresponding sector on the replacement drive cannot be reconstructed. Data is lost. In the drive industry, the measurement of how often this occurs is called the Bit Error
Re: Software based SATA RAID-5 expandable arrays?
Ahh... guess it's time to upgrade again My plan was to start off with 3 drives in a RAID5, and slowly grow it up to maybe 6 or 7 drives before converting it over to a RAID6, and then topping it out at 12 drives (all I can fit in the case) The performace hit isn't going to bother me too much - it's mainly going to be for video for my media server for the house... So.. Can I expand a RAID6 now, which is good But can I change from RAID5 to RAID6 whilst online? Graham - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Wednesday, 11 July, 2007 11:03:34 AM Subject: RE: Software based SATA RAID-5 expandable arrays? That was true up to kernel 2.6.21 and 2.6 mdadm where support for RAID 6 reshape arrived. I have reshaped (added additional drives) to my RAID 6 twice now with no problems in the past few months. You mentioned that as the only disadvantage. There are other things to consider. The overhead for parity of course. You can't have a RAID 6 with only three drives unless you build it with a missing drive and run degraded. Also (my opinion) it might not worth the overhead with only 4 drives, unless you plan to reshape (add drives) down the road. When you have an array with several drives, than it is more advantages as the percentage of disk space lost to parity goes down [((2/N)*100) where N is the number of drives in the array] so your storage efficiency increases ((Number of Drives -2)/Number of Drives). And with more drives the statistics of getting hit with a bit error after you lose a drive and you are trying to rebuild increases. Also, there is a very slight performance drop for write speeds on RAID6 since you are calculating p and q parity. But for what I use my system for, family digital photos, file storage and media server I mostly read data and not bothered with slight performance hit in write. I have been using RAID6 with 10 disk for over a year and it has saved me at least once. As far as converting the RAID6 to RAID5 or RAID4... Never had a need to do this, but no probably not. Dan. - Inline Message Follows - To: Daniel Korstad ; Michael Cc: linux-raid@vger.kernel.org From: jahammonds prost Subject: Re: Software based SATA RAID-5 expandable arrays? Why do I use RAID6? For the extra redundancy I've been thinking about RAID6 too, having been bitten a couple of times the only disadvantage that I can see at the moment is that you can't convert and grow it... ie... I can't convert from a 4 drive RAID5 array to a 5 drive RAID6 one when I add an additional drive... I also don't think that you can grow a RAID6 array at the moment - I'd want to add additional drives over a few months as they come on sale Or am I wrong on both counts? Graham - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html ___ Yahoo! Answers - Got a question? Someone out there knows the answer. Try it now. http://uk.answers.yahoo.com/ - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Software based SATA RAID-5 expandable arrays?
Currently, no you can't. However it is on the TODO list. http://neil.brown.name/blog/20050727143147-003 Maybe by the end of the year, Neil hit his goal on the raid6 grow for kernel 2.6.21... But Neil states the raid 5 to raid 6 is more complex to implement... Dan. - Original Message - From: jahammonds prost Sent: Wed, 7/11/2007 12:26pm To: Daniel Korstad Cc: linux-raid@vger.kernel.org Subject: Re: Software based SATA RAID-5 expandable arrays? Ahh... guess it's time to upgrade again My plan was to start off with 3 drives in a RAID5, and slowly grow it up to maybe 6 or 7 drives before converting it over to a RAID6, and then topping it out at 12 drives (all I can fit in the case) The performace hit isn't going to bother me too much - it's mainly going to be for video for my media server for the house... So.. Can I expand a RAID6 now, which is good But can I change from RAID5 to RAID6 whilst online? Graham - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Wednesday, 11 July, 2007 11:03:34 AM Subject: RE: Software based SATA RAID-5 expandable arrays? That was true up to kernel 2.6.21 and 2.6 mdadm where support for RAID 6 reshape arrived. I have reshaped (added additional drives) to my RAID 6 twice now with no problems in the past few months. You mentioned that as the only disadvantage. There are other things to consider. The overhead for parity of course. You can't have a RAID 6 with only three drives unless you build it with a missing drive and run degraded. Also (my opinion) it might not worth the overhead with only 4 drives, unless you plan to reshape (add drives) down the road. When you have an array with several drives, than it is more advantages as the percentage of disk space lost to parity goes down [((2/N)*100) where N is the number of drives in the array] so your storage efficiency increases ((Number of Drives -2)/Number of Drives). And with more drives the statistics of getting hit with a bit error after you lose a drive and you are trying to rebuild increases. Also, there is a very slight performance drop for write speeds on RAID6 since you are calculating p and q parity. But for what I use my system for, family digital photos, file storage and media server I mostly read data and not bothered with slight performance hit in write. I have been using RAID6 with 10 disk for over a year and it has saved me at least once. As far as converting the RAID6 to RAID5 or RAID4... Never had a need to do this, but no probably not. Dan. - Inline Message Follows - To: Daniel Korstad ; Michael Cc: linux-raid@vger.kernel.org From: jahammonds prost Subject: Re: Software based SATA RAID-5 expandable arrays? Why do I use RAID6? For the extra redundancy I've been thinking about RAID6 too, having been bitten a couple of times the only disadvantage that I can see at the moment is that you can't convert and grow it... ie... I can't convert from a 4 drive RAID5 array to a 5 drive RAID6 one when I add an additional drive... I also don't think that you can grow a RAID6 array at the moment - I'd want to add additional drives over a few months as they come on sale Or am I wrong on both counts? Graham - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html ___ Yahoo! Answers - Got a question? Someone out there knows the answer. Try it now. http://uk.answers.yahoo.com/ - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Software based SATA RAID-5 expandable arrays?
And if I were a betting man, I would guess you will need to add a physical drive to execute a RAID5 to RAID6 conversation for adding additional parity even if your current RAID5 is not full of data. So if your case only holds 12 Drives, I would not grow your RAID5 to 12 drives and expect to be able to convert to RAID6 with the same 12 drives even if they are not full of data. But that is just my guess on a feature that does not even exist yet... Dan. - Original Message - From: [EMAIL PROTECTED] on behalf of Daniel Korstad Sent: Wed, 7/11/2007 2:14pm To: jahammonds prost Cc: linux-raid@vger.kernel.org Subject: RE: Software based SATA RAID-5 expandable arrays? Currently, no you can't. However it is on the TODO list. http://neil.brown.name/blog/20050727143147-003 Maybe by the end of the year, Neil hit his goal on the raid6 grow for kernel 2.6.21... But Neil states the raid 5 to raid 6 is more complex to implement... Dan. - Original Message - From: jahammonds prost Sent: Wed, 7/11/2007 12:26pm To: Daniel Korstad Cc: linux-raid@vger.kernel.org Subject: Re: Software based SATA RAID-5 expandable arrays? Ahh... guess it's time to upgrade again My plan was to start off with 3 drives in a RAID5, and slowly grow it up to maybe 6 or 7 drives before converting it over to a RAID6, and then topping it out at 12 drives (all I can fit in the case) The performace hit isn't going to bother me too much - it's mainly going to be for video for my media server for the house... So.. Can I expand a RAID6 now, which is good But can I change from RAID5 to RAID6 whilst online? Graham - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Wednesday, 11 July, 2007 11:03:34 AM Subject: RE: Software based SATA RAID-5 expandable arrays? That was true up to kernel 2.6.21 and 2.6 mdadm where support for RAID 6 reshape arrived. I have reshaped (added additional drives) to my RAID 6 twice now with no problems in the past few months. You mentioned that as the only disadvantage. There are other things to consider. The overhead for parity of course. You can't have a RAID 6 with only three drives unless you build it with a missing drive and run degraded. Also (my opinion) it might not worth the overhead with only 4 drives, unless you plan to reshape (add drives) down the road. When you have an array with several drives, than it is more advantages as the percentage of disk space lost to parity goes down [((2/N)*100) where N is the number of drives in the array] so your storage efficiency increases ((Number of Drives -2)/Number of Drives). And with more drives the statistics of getting hit with a bit error after you lose a drive and you are trying to rebuild increases. Also, there is a very slight performance drop for write speeds on RAID6 since you are calculating p and q parity. But for what I use my system for, family digital photos, file storage and media server I mostly read data and not bothered with slight performance hit in write. I have been using RAID6 with 10 disk for over a year and it has saved me at least once. As far as converting the RAID6 to RAID5 or RAID4... Never had a need to do this, but no probably not. Dan. - Inline Message Follows - To: Daniel Korstad ; Michael Cc: linux-raid@vger.kernel.org From: jahammonds prost Subject: Re: Software based SATA RAID-5 expandable arrays? Why do I use RAID6? For the extra redundancy I've been thinking about RAID6 too, having been bitten a couple of times the only disadvantage that I can see at the moment is that you can't convert and grow it... ie... I can't convert from a 4 drive RAID5 array to a 5 drive RAID6 one when I add an additional drive... I also don't think that you can grow a RAID6 array at the moment - I'd want to add additional drives over a few months as they come on sale Or am I wrong on both counts? Graham - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html ___ Yahoo! Answers - Got a question? Someone out there knows the answer. Try it now. http://uk.answers.yahoo.com/ - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
How would I be able to generate a report and email it to me, based on this cron jobs check disk results, any important reports based on the SMART Disk information, and/or drive failure reported if a disk failed. I am running Suse, and the check program is not available, I like Suse since it is easy to use, supports all of my hardware right on install and has the auto update features that I enjoy. I have instead I have seen a report of tune2fs (which is available), though I am not sure if this is of use on a RAID-5 array. Thanks Michael Parisi - Original Message From: Bill Davidsen [EMAIL PROTECTED] To: Daniel Korstad [EMAIL PROTECTED] Cc: Michael [EMAIL PROTECTED]; linux-raid@vger.kernel.org Sent: Wednesday, July 11, 2007 10:21:42 AM Subject: Re: Software based SATA RAID-5 expandable arrays? Daniel Korstad wrote: You have lots of options. This will be a lengthy response and will give just some ideas for just some of the options... Just a few thoughts below interspersed with your comments. For my server, I had started out with a single drive. I later migrated to migrate to a RAID 1 mirror (after having to deal with reinstalls after drive failures I wised up). Since I already had an OS that I wanted to keep, my RAID-1 setup was a bit more involved. I following this migration to get me there; http://wiki.clug.org.za/wiki/RAID-1_in_a_hurry_with_grub_and_mdadm Since you are starting from scratch, it should be easier for you. Most distros will have an installer that will guide you though the process. When you get to hard drive partitioning, look for an advance option or review and modify partition layout option or something similar otherwise it might just make a guess of what you want and that would not be RAID. In this advance partition setup, you will be able to create your RAID. First you make equal size partitions on both physical drives. For example, first carve out 100M partition on each of the two physical OS drives, than make a RAID 1 md0 with each of this partitions and than make this your /boot. Do this again for other partitions you want to have RAIDed. You can do this for /boot, /var, /home, /tmp, /usr. This is can be nice to have a separations incase a user fills /home/foo with crap and this will not effect other parts of the OS, or if mail spool fills up, it will not hang the OS. Only problem it determining how big to make them during the install. At a minimum, I would do three partitions; /boot, swap, and / This means all the others (/var, /home, /tmp, /usr) are in the / partition but this way you don't have to worry about sizing them all correctly. For the simplest setup, I would do RAID 1 for /boot (md0), swap (md1), and / (md2) (Alternatively, your could make a swap file in / and not have a swap partition, tons of options...) Do you need to RAID your swap? Well, I would RAID it or make a swap file within a RAID partition. If you don't and your system is using swap and you lose a drive that has swap information/partition on it, you might have issues depending on how important that information in the failed drive was. You systems might hang. Note that RAID-10 generally performs better than mirroring, particularly when more than a few drives are involved. This can have performance implications for swap, when large i/o pushes program pages out of memory. The other side of that coin is that recovery CDs don't seem to know how to use RAID-10 swap, which might be an issue on some systems. After you go through the install and have a bootable OS that is running on mdadm RAID, I would test it to make sure grub was installed correctly to both the physical drives. If grub is not installed to both drives, and you lose one drive down the road and if that one was the one with grub, you will have a system that will not boot even though it has a second drive with a copy of all the files. If this were to happen, you can recover by booting with a bootable linux CD or recover disk and manually installing grub too. For example say you only had grub installed to hda and it failed, boot with a live linux cd and type (assuming /dev/hdd is the surviving second drive); grub device (hd0) /dev/hdd root (hd0,0) setup (hd0) quit You say you are using two 500G drives for the OS. You don't necessary have to use all the space for the OS. You can make your partitions and take the left over space and throw it into a logical volume. This logical volume would not be fault tolerant, but would be the sum of the left over capacity from both drives. For example, you use 100M for /boot and 200G for / and 2G for swap. Take the rest and make a standard ext3 partition for the remaining space on both drives and put them in a logical volume giving over 500G to play with for non critical crap. Why do I use RAID6? For the extra redundancy and I have 10 drives in my
Re: Software based SATA RAID-5 expandable arrays?
Yeah... I kinda suspected that it would need to be a new drive being added - which is fine by me. I'm in the planning stages for building my next home server... One way to do it (with what we have at the moment) would be to have enough drives setup for RAID5, and build an empty RAID6 array. Move the data over, then destroy the old array, and grow out the new one with the recovered disks Ick... but I that works. Graham - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: jahammonds prost [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Wednesday, 11 July, 2007 3:26:51 PM Subject: RE: Software based SATA RAID-5 expandable arrays? And if I were a betting man, I would guess you will need to add a physical drive to execute a RAID5 to RAID6 conversation for adding additional parity even if your current RAID5 is not full of data. So if your case only holds 12 Drives, I would not grow your RAID5 to 12 drives and expect to be able to convert to RAID6 with the same 12 drives even if they are not full of data. But that is just my guess on a feature that does not even exist yet... Dan. - Original Message - From: [EMAIL PROTECTED] on behalf of Daniel Korstad Sent: Wed, 7/11/2007 2:14pm To: jahammonds prost Cc: linux-raid@vger.kernel.org Subject: RE: Software based SATA RAID-5 expandable arrays? Currently, no you can't. However it is on the TODO list. http://neil.brown.name/blog/20050727143147-003 Maybe by the end of the year, Neil hit his goal on the raid6 grow for kernel 2.6.21... But Neil states the raid 5 to raid 6 is more complex to implement... Dan. - Original Message - From: jahammonds prost Sent: Wed, 7/11/2007 12:26pm To: Daniel Korstad Cc: linux-raid@vger.kernel.org Subject: Re: Software based SATA RAID-5 expandable arrays? Ahh... guess it's time to upgrade again My plan was to start off with 3 drives in a RAID5, and slowly grow it up to maybe 6 or 7 drives before converting it over to a RAID6, and then topping it out at 12 drives (all I can fit in the case) The performace hit isn't going to bother me too much - it's mainly going to be for video for my media server for the house... So.. Can I expand a RAID6 now, which is good But can I change from RAID5 to RAID6 whilst online? Graham - Original Message From: Daniel Korstad [EMAIL PROTECTED] To: [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Wednesday, 11 July, 2007 11:03:34 AM Subject: RE: Software based SATA RAID-5 expandable arrays? That was true up to kernel 2.6.21 and 2.6 mdadm where support for RAID 6 reshape arrived. I have reshaped (added additional drives) to my RAID 6 twice now with no problems in the past few months. You mentioned that as the only disadvantage. There are other things to consider. The overhead for parity of course. You can't have a RAID 6 with only three drives unless you build it with a missing drive and run degraded. Also (my opinion) it might not worth the overhead with only 4 drives, unless you plan to reshape (add drives) down the road. When you have an array with several drives, than it is more advantages as the percentage of disk space lost to parity goes down [((2/N)*100) where N is the number of drives in the array] so your storage efficiency increases ((Number of Drives -2)/Number of Drives). And with more drives the statistics of getting hit with a bit error after you lose a drive and you are trying to rebuild increases. Also, there is a very slight performance drop for write speeds on RAID6 since you are calculating p and q parity. But for what I use my system for, family digital photos, file storage and media server I mostly read data and not bothered with slight performance hit in write. I have been using RAID6 with 10 disk for over a year and it has saved me at least once. As far as converting the RAID6 to RAID5 or RAID4... Never had a need to do this, but no probably not. Dan. - Inline Message Follows - To: Daniel Korstad ; Michael Cc: linux-raid@vger.kernel.org From: jahammonds prost Subject: Re: Software based SATA RAID-5 expandable arrays? Why do I use RAID6? For the extra redundancy I've been thinking about RAID6 too, having been bitten a couple of times the only disadvantage that I can see at the moment is that you can't convert and grow it... ie... I can't convert from a 4 drive RAID5 array to a 5 drive RAID6 one when I add an additional drive... I also don't think that you can grow a RAID6 array at the moment - I'd want to add additional drives over a few months as they come on sale Or am I wrong on both counts? Graham - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html ___ Yahoo! Answers - Got a question? Someone out there knows
Re: Software based SATA RAID-5 expandable arrays?
On 11 Jul 2007, Michael stated: I am running Suse, and the check program is not available `check' isn't a program. The line suggested has a typo: it should be something like this: 30 2 * * Mon echo check /sys/block/md0/md/sync_action The only program that line needs is `echo' and I'm sure you've got that. (You also need to have sysfs mounted at /sys, but virtually everyone has their systems set up like that nowadays.) (obviously you can check more than one array: just stick in other lines that echo `check' into some other mdN at some other time of day.) -- `... in the sense that dragons logically follow evolution so they would be able to wield metal.' --- Kenneth Eng's colourless green ideas sleep furiously - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
From: Brad Campbell [EMAIL PROTECTED] I've got 2 boxes. One has 14 drives and a 480W PSU and the other has 15 drives and a 600W PSU. It's not rocket science. Where did you find reasonably priced cases to hold so many drives? Each of my home servers top out at 8 data drives each - plus a 20Gb one to boot from. Graham - Original Message From: Brad Campbell [EMAIL PROTECTED] To: greenjelly [EMAIL PROTECTED] Cc: linux-raid@vger.kernel.org Sent: Wednesday, 20 June, 2007 4:52:38 PM Subject: Re: Software based SATA RAID-5 expandable arrays? greenjelly wrote: The options I seek are to be able to start with a 6 Drive array RAID-5 array, then as my demand for more space increases in the future I want to be able to plug in more drives and incorporate them into the Array without the need to backup the data. Basically I need the software to add the drive/drives to the Array, then Rebuild the array incorporating the new drives while preserving the data on the original array. I've got 2 boxes. One has 14 drives and a 480W PSU and the other has 15 drives and a 600W PSU. It's not rocket science. Put a lot of drives in a box, make sure you have enough sata ports and power to go around (watch your peak 12V consumption on spin up really) and use linux md. Easy.. Oh, but make sure the drives stay cool! For a cheap-o home server (which is what I have) I'd certainly not bother with a dedicated RAID card. You are not even going to need GB ethernet really.. I've got 15 drives on a single PCI bus, it's as slow as a wet week in may (in the southern hemisphere), but I'm streaming to 3 head units which total a combined 5MB/s if I'm lucky.. Rebuilds can take up to 10 hours though. QUESTIONS Since this is a media server, and would only be used to serve Movies and Video to my two machines It wouldn't have to be powered up full time (My Music consumes less space and will be contained on two seperate machines). Is there a way to considerably lower the power consumption of this server the 90% of time its not in use? Yes, don't poll for SMART and spin down the drives when idle (man hdparm). Use S3 sleep and WOL if you are really clever. (I'm not, my boxes live in a dedicated server room with its own AC, but that's because I'm nuts). I also have over 25k hours on the drives because I don't spin them down. I figure the extra power is a trade off for drive life. They've got less than 50 spin cycles on them in over 25k hours.. Can Linux support Drive Arrays of Significant Sizes (4-8 terabytes)? Yes, easily (6TB here) Can Linux Software support RAID-5 expandability, allowing me to increase the number of disks in the array, without the need to backup the media, recreate the array from scratch and then copy the backup to the machine (something I will be unable to do)? Yes but get a cheap UPS at least (it's cheap insurance) I know this is a Linux forum, but I figure many of you guys work with Windows Server. If so does Windows 2003 provide the same support for the requested requirements above? Why would you even _ask_ ?? Read the man page for mdadm, then read it again (and a third time). Then google for Raid-5 two drive failure linux just to familiarise yourself with the background. What you are doing has been done before many, many times. There are some well written sites out there relating to building exactly what you want to build with great detail. If you are serious about using windows, I pity you.. Linux (actually a combination of the kernel md layer and mdadm) makes it so easy you'd be nuts to beat your head against the wall with the alternative. Brad -- Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so. -- Douglas Adams - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html ___ To help you stay safe and secure online, we've developed the all new Yahoo! Security Centre. http://uk.security.yahoo.com - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
jahammonds prost wrote: From: Brad Campbell [EMAIL PROTECTED] I've got 2 boxes. One has 14 drives and a 480W PSU and the other has 15 drives and a 600W PSU. It's not rocket science. Where did you find reasonably priced cases to hold so many drives? Each of my home servers top out at 8 data drives each - plus a 20Gb one to boot from. For one of them I used a modified CD duplicator case (9 5.25 bays) and the other one I used a nice tall tower. All except 4 drives are in Supermicro hotswap bays. Aside from the Supermicro bays (which do look nice and keep the drives very cool) these machines are chewing gum and duct tape jobs. http://i10.photobucket.com/albums/a109/ytixelprep/F.jpg Having said that, they are chewing gum and duct tape jobs that have had a downtime of less than 4 hrs/year over the last 3 years. Brad -- Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so. -- Douglas Adams - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
Michael wrote: Thank you; Not that I want to, but where did you find a SATA PCI card that fit 15 drives? Areca have a few - a range of PCI-X cards that do up to 24 SATA drives (ARC-1170) and PCI-e up to 24 drives (ARC-1280). Regards, Richard - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
greenjelly wrote: The options I seek are to be able to start with a 6 Drive array RAID-5 array, then as my demand for more space increases in the future I want to be able to plug in more drives and incorporate them into the Array without the need to backup the data. Basically I need the software to add the drive/drives to the Array, then Rebuild the array incorporating the new drives while preserving the data on the original array. I've got 2 boxes. One has 14 drives and a 480W PSU and the other has 15 drives and a 600W PSU. It's not rocket science. Put a lot of drives in a box, make sure you have enough sata ports and power to go around (watch your peak 12V consumption on spin up really) and use linux md. Easy.. Oh, but make sure the drives stay cool! For a cheap-o home server (which is what I have) I'd certainly not bother with a dedicated RAID card. You are not even going to need GB ethernet really.. I've got 15 drives on a single PCI bus, it's as slow as a wet week in may (in the southern hemisphere), but I'm streaming to 3 head units which total a combined 5MB/s if I'm lucky.. Rebuilds can take up to 10 hours though. QUESTIONS Since this is a media server, and would only be used to serve Movies and Video to my two machines It wouldn't have to be powered up full time (My Music consumes less space and will be contained on two seperate machines). Is there a way to considerably lower the power consumption of this server the 90% of time its not in use? Yes, don't poll for SMART and spin down the drives when idle (man hdparm). Use S3 sleep and WOL if you are really clever. (I'm not, my boxes live in a dedicated server room with its own AC, but that's because I'm nuts). I also have over 25k hours on the drives because I don't spin them down. I figure the extra power is a trade off for drive life. They've got less than 50 spin cycles on them in over 25k hours.. Can Linux support Drive Arrays of Significant Sizes (4-8 terabytes)? Yes, easily (6TB here) Can Linux Software support RAID-5 expandability, allowing me to increase the number of disks in the array, without the need to backup the media, recreate the array from scratch and then copy the backup to the machine (something I will be unable to do)? Yes but get a cheap UPS at least (it's cheap insurance) I know this is a Linux forum, but I figure many of you guys work with Windows Server. If so does Windows 2003 provide the same support for the requested requirements above? Why would you even _ask_ ?? Read the man page for mdadm, then read it again (and a third time). Then google for Raid-5 two drive failure linux just to familiarise yourself with the background. What you are doing has been done before many, many times. There are some well written sites out there relating to building exactly what you want to build with great detail. If you are serious about using windows, I pity you.. Linux (actually a combination of the kernel md layer and mdadm) makes it so easy you'd be nuts to beat your head against the wall with the alternative. Brad -- Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so. -- Douglas Adams - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
On Tuesday 19 June 2007 10:35:47 David Greaves wrote: Dexter Filmore wrote: Why dontcha just cut all the look how big my ePenis is chatter and tell us what you wanna do? Nobody gives a rat if your ultra1337 sound cards needs a 10 megawatt power supply. Chill Dexter. How many faults have you seen on this list attributed to poor PSUs? How many people whinge about the performance of their controllers/setups 'cos they find out _after_ they bought them just how naff they are? A 750W supply doesn't increase server stability - that's what redundant PSUs are for. Plus: there are sh!tty 750W-PSUs otu there as well - numbers mean jack. Sure he went a bit OTT in the description - but if you'd rather see Hey dudez, what do I need for a really quick server then #linux is good :) He's clearly new to linux, (and granted, maybe a bit over-excited by hardware!) but give the guy a break. He very clearly told us what he wanted to do in the QUESTIONs bit. Could have done right from the start instead of immersing into Vista, X-Fi 8800 and Radeon. And don't think too badly of Dexter, he's usually OK. Guess I had a newbie overdose since migrating the desktop box to Kubuntu. David PS, Dex, I wonder who posted these noobie sounding question in April last year: I'm currently planning my first raid array. I intend to go for softraid (budget's the limiting factor), not sure about 5 or 6 yet. Plan so far: build a raid5 from 3 disks, later add a disk and reconf to raid6. Question: is that possible at all? Can a raid5 be reconfed to a raid6 with raidreconf? Next Question: how stable is it? Will I likely get away without making backups or is there like a 10% chance of failure? Other precautions advised? Yes? What about that? All tech questions regarding file servers and raid setups on Linux. Don't see how I go about how my Radeon makes the 10k barrier in 3Dmark. Nuff said. -- -BEGIN GEEK CODE BLOCK- Version: 3.12 GCS d--(+)@ s-:+ a- C UL++ P+++ L+++ E-- W++ N o? K- w--(---) !O M+ V- PS+ PE Y++ PGP t++(---)@ 5 X+(++) R+(++) tv--(+)@ b++(+++) DI+++ D- G++ e* h++ r* y? --END GEEK CODE BLOCK-- http://www.stop1984.com http://www.againsttcpa.com - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
My 750w PSU is going into my dream machine (Overclocked core2duo extreme with 1066mhz memory, lots of optical drives, water cooling, Radion 1900xtx, aka high power application). The 550 Ultra is coming out of that machine and going into the NAS. Its not the perfect solution, for I would prefer a high efficiency PSU for the NAS, but it is the inexpensive solution. These details are why I tried to be clear and include as much info as possible. My NAS may grow to 20 or more drives, thus making me feel nice and warm with a higher powered PSU. The Higher spec PSU, may also save me from a possible PSU failure due to a fan failure (which is the number one cause of PSU failure). - Original Message From: Dexter Filmore [EMAIL PROTECTED] To: David Greaves [EMAIL PROTECTED] Cc: greenjelly [EMAIL PROTECTED]; linux-raid@vger.kernel.org Sent: Tuesday, June 19, 2007 4:14:09 AM Subject: Re: Software based SATA RAID-5 expandable arrays? On Tuesday 19 June 2007 10:35:47 David Greaves wrote: Dexter Filmore wrote: Why dontcha just cut all the look how big my ePenis is chatter and tell us what you wanna do? Nobody gives a rat if your ultra1337 sound cards needs a 10 megawatt power supply. Chill Dexter. How many faults have you seen on this list attributed to poor PSUs? How many people whinge about the performance of their controllers/setups 'cos they find out _after_ they bought them just how naff they are? A 750W supply doesn't increase server stability - that's what redundant PSUs are for. Plus: there are sh!tty 750W-PSUs otu there as well - numbers mean jack. Sure he went a bit OTT in the description - but if you'd rather see Hey dudez, what do I need for a really quick server then #linux is good :) He's clearly new to linux, (and granted, maybe a bit over-excited by hardware!) but give the guy a break. He very clearly told us what he wanted to do in the QUESTIONs bit. Could have done right from the start instead of immersing into Vista, X-Fi 8800 and Radeon. And don't think too badly of Dexter, he's usually OK. Guess I had a newbie overdose since migrating the desktop box to Kubuntu. David PS, Dex, I wonder who posted these noobie sounding question in April last year: I'm currently planning my first raid array. I intend to go for softraid (budget's the limiting factor), not sure about 5 or 6 yet. Plan so far: build a raid5 from 3 disks, later add a disk and reconf to raid6. Question: is that possible at all? Can a raid5 be reconfed to a raid6 with raidreconf? Next Question: how stable is it? Will I likely get away without making backups or is there like a 10% chance of failure? Other precautions advised? Yes? What about that? All tech questions regarding file servers and raid setups on Linux. Don't see how I go about how my Radeon makes the 10k barrier in 3Dmark. Nuff said. -- -BEGIN GEEK CODE BLOCK- Version: 3.12 GCS d--(+)@ s-:+ a- C UL++ P+++ L+++ E-- W++ N o? K- w--(---) !O M+ V- PS+ PE Y++ PGP t++(---)@ 5 X+(++) R+(++) tv--(+)@ b++(+++) DI+++ D- G++ e* h++ r* y? --END GEEK CODE BLOCK-- http://www.stop1984.com http://www.againsttcpa.com Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search http://search.yahoo.com/search?fr=oni_on_mailp=graduation+giftscs=bz - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Software based SATA RAID-5 expandable arrays?
On 19 Jun 2007, Michael outgrape: [regarding `welcome to my killfile'] Grow up man, and I thanks for the threat. I will take that into account if anything bad happens to my computer system. Read http://en.wikipedia.org/wiki/Killfile and learn. All he's saying is `I am automatically ignoring you'. - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: Software based SATA RAID-5 expandable arrays?
Last I check expanding drives (reshaping the RAID) in a raid set within Windows is not supported. Significant size is relative I guess, but 4-8 terabytes will not be a problem in either OS. I run a RAID 6 (Windows does not support this either last I checked). I started out with 5 drives and have reshaped it to ten drives now. I have a few 250G (old original drives) and many 500G drives (added and replacement drives) in the set. Once all the old 250G die off and I replace them with 500G drives I will grow the RAID to the size of its new smallest disk, 500G. Grow and Reshape are slightly different, both supported in Linux mdadm. I have tested both with succcess. I too use my set for media and it is not in use 90% of the time. I use put this line in my /etc/rc.local to put the drives to sleep after a specified min of inactivity; hdparm -S 241 /dev/sd* The values for the -S switch are not intuitive, read the man page. The value I use (241) put them to standby (spindown) after 30min. My OS is on EIDE and my RAID set is all SATA, hence the splat for all SATA drives. I have been running this for a year now with my RAID set. It works great and I have had no problems with mdadm waiting on drives to spinup when I access them. The one caveat, be prepared to wait a few moments if the are all in spindown state before you can access your data. For me with ten drives, it is always less than a minute, usually 30sec or so. For a filesystem, I use XFS for my large media files. Dan. - Inline Message Follows - To: linux-raid@vger.kernel.org From: greenjelly Subject: Software based SATA RAID-5 expandable arrays? I am researching my option to build a Media NAS server. Sorry for the long message, but I wanted to provide as much details as possible to my problem, for the best solution. I have Bolded sections as to save people who don't have the time to read all of this. Option 1: Expand My current Dream Machine! I could buying a RAID-5 Hardware card for my current system (vista ultimate 64 with a extreme 6800 and 1066mb 2 gig RAM). The Adaptec RAID controller (model 3805, you can search NewEgg for the infomation) will cost me near $500 (consume 23w) and support 8 drives (I have 6). This controller contains a 800mhz processor with a large cache of memory. It will support expandable RAID-5 array! I would also buy a 750w+ PSU (for the additional safety and security). The drives in this machine would be placed in shock absorbing (noise reduction) 3 slot 4 drive bay containers with fans ( I have 2 of these) and I will be removing a IDE based Pioneer DVD Burner (1 of 3) because of its flaky performance given the p965 intel chip set lack of native IDE support and thus the Motherboards Micron SATA to IDE device. Ive already installed 4 drives in this machine (on the native MB SATA controller) only to find a fan fail on me within days of the installation. One of the drives went bad (may or may not have to do with the heat). There are 5mm between these drives, and I would now replace both fans with higher RPM ball baring fans for added reliability (more noise). I would also need to find a Freeware SMART monitor software which at this time I can not find for Vista, to warn me of increased temps due to failure of fan, increased environmental heat, etc. The only option is commercial SMART monitoring software (which may not work with the Adaptec RAID adapter. Option 2: Build a server. I have a copy of Windows 2003 server, which I have yet to find out if it supports native software expandable RAID-5 arrays. I can also use Linux (which I have very little experience with) but have always wanted to use and learn. To do either of the last two options, I would still need to buy a new power supply for my current VISTA machine (for added reliability). The current PSU is 550w and with a power hungry RADEON, 3 DVD Drives and a X-Fi sound card... My nerves are getting frayed. I would buy a cheap motherboard, processor and 1gig or less of RAM. Lastly I would want a VERY large Case. I have a 7300 NVidia PCI card that was replaced with a X1950GT on my Home Theater PC so that I may play back HD/Blue Ray DVD's. The server option may cost a bit more then the $500 for the Adaptec Raid controller. This will only work if Linux or Windows 2003 supports my much needed requirements. My Linux OS will be installed on a 40mb IDE Drive (not part of the Array). The options I seek are to be able to start with a 6 Drive array RAID-5 array, then as my demand for more space increases in the future I want to be able to plug in more drives and incorporate them into the Array without the need to backup the data. Basically I need the software to add the drive/drives to the Array, then Rebuild the array incorporating the new drives while preserving the data on the original array. QUESTIONS Since this is a media server, and would only be used to serve Movies and Video to my two machines
Re: Software based SATA RAID-5 expandable arrays?
Why dontcha just cut all the look how big my ePenis is chatter and tell us what you wanna do? Nobody gives a rat if your ultra1337 sound cards needs a 10 megawatt power supply. -- -BEGIN GEEK CODE BLOCK- Version: 3.12 GCS d--(+)@ s-:+ a- C UL++ P+++ L+++ E-- W++ N o? K- w--(---) !O M+ V- PS+ PE Y++ PGP t++(---)@ 5 X+(++) R+(++) tv--(+)@ b++(+++) DI+++ D- G++ e* h++ r* y? --END GEEK CODE BLOCK-- http://www.stop1984.com http://www.againsttcpa.com - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
