raid10 on centos 5
I am trying to set up raid 10 and so far with no luck. I have 4 drives, and Anaconda will not let me do raid 10. mdadm doesn't have the raid 10 personality loaded. When I create the array manually like so: 2 drives in /dev/md11 as raid1 2 drives in /dev/md12 as raid1 md11 and md12 in /dev/md10 as raid0 Everything looks fine from the shell, but anaconda only sees md11 and md12. The only choice I see is to set up LVM over md11 and md12. Is this really raid10? Russ - 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: raid10 on centos 5
No LVM over the two RAID 1's is more like RAID 1c which is just a concatenation of RAID 1's. You don't get the striping that you get in RAID 10. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ruslan Sivak Sent: Friday, May 04, 2007 11:22 AM To: linux-raid@vger.kernel.org Subject: raid10 on centos 5 I am trying to set up raid 10 and so far with no luck. I have 4 drives, and Anaconda will not let me do raid 10. mdadm doesn't have the raid 10 personality loaded. When I create the array manually like so: 2 drives in /dev/md11 as raid1 2 drives in /dev/md12 as raid1 md11 and md12 in /dev/md10 as raid0 Everything looks fine from the shell, but anaconda only sees md11 and md12. The only choice I see is to set up LVM over md11 and md12. Is this really raid10? Russ - 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: raid10 on centos 5
[EMAIL PROTECTED] wrote: No LVM over the two RAID 1's is more like RAID 1c which is just a concatenation of RAID 1's. You don't get the striping that you get in RAID 10. That's what I guessed. Can anyone let me know if it's possible to set up a real md raid10? Do I need to custom compile the kernel and do a kickstart install or something? Russ - 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: raid10 on centos 5
cat /proc/mdstat is the raid10 personality installed? On Fri, 4 May 2007, Ruslan Sivak wrote: [EMAIL PROTECTED] wrote: No LVM over the two RAID 1's is more like RAID 1c which is just a concatenation of RAID 1's. You don't get the striping that you get in RAID 10. That's what I guessed. Can anyone let me know if it's possible to set up a real md raid10? Do I need to custom compile the kernel and do a kickstart install or something? Russ - 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: raid10 on centos 5
Justin Piszcz wrote: cat /proc/mdstat is the raid10 personality installed? No, it's not. How would I go about installing it? Personalities: [raid0] [raid1] [raid6] [raid5] [raid4] Russ - 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: raid10 on centos 5
Compile into the kernel, boot new kernel then create your RAID 10 volume with mdadm :) On Fri, 4 May 2007, Ruslan Sivak wrote: Justin Piszcz wrote: cat /proc/mdstat is the raid10 personality installed? No, it's not. How would I go about installing it? Personalities: [raid0] [raid1] [raid6] [raid5] [raid4] Russ - 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: raid10 on centos 5
Justin Piszcz wrote: Compile into the kernel, boot new kernel then create your RAID 10 volume with mdadm :) So a custom kernel is needed? Is there a way to do a kickstart install with the new kernel? Or better yet, put it on the install cd? Russ - 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: raid10 on centos 5
Unsure for CentOS, I use Debian and always compile my own kernel. Justin. On Fri, 4 May 2007, Ruslan Sivak wrote: Justin Piszcz wrote: Compile into the kernel, boot new kernel then create your RAID 10 volume with mdadm :) So a custom kernel is needed? Is there a way to do a kickstart install with the new kernel? Or better yet, put it on the install cd? Russ - 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: raid10 on centos 5
Ruslan Sivak wrote: So a custom kernel is needed? Is there a way to do a kickstart install with the new kernel? Or better yet, put it on the install cd? have you tried: modprobe raid10 ? David - 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: raid10 on centos 5
David Greaves wrote: Ruslan Sivak wrote: So a custom kernel is needed? Is there a way to do a kickstart install with the new kernel? Or better yet, put it on the install cd? have you tried: modprobe raid10 ? David Yes, no such luck. Russ - 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: raid10 on centos 5
} -Original Message- } From: [EMAIL PROTECTED] [mailto:linux-raid- } [EMAIL PROTECTED] On Behalf Of Ruslan Sivak } Sent: Friday, May 04, 2007 12:22 PM } To: linux-raid@vger.kernel.org } Subject: raid10 on centos 5 } } I am trying to set up raid 10 and so far with no luck. I have 4 drives, } and Anaconda will not let me do raid 10. mdadm doesn't have the raid 10 } personality loaded. When I create the array manually like so: } } 2 drives in /dev/md11 as raid1 } 2 drives in /dev/md12 as raid1 } md11 and md12 in /dev/md10 as raid0 } } Everything looks fine from the shell, but anaconda only sees md11 and } md12. } } The only choice I see is to set up LVM over md11 and md12. Is this } really raid10? } } Russ You are making a RAID1+RAID0 array. Try making a real RAID10 array with 4 drives. This way you would only have 1 array with 4 drives. From the mdadm man page: Currently, Linux supports LINEAR md devices, RAID0 (striping), RAID1 (mirroring), RAID4, RAID5, RAID6, RAID10, MULTIPATH, and FAULTY. Notice RAID10 is listed, use that. Man mdadm for more info. However, I would (and do) use RAID6. With RAID6 any 2 disks can fail without data loss. With RAID1+RAID0, any one disk can fail, a second failure has a 1 in 3 chance of vast data loss. I hope this helps, Guy - 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: raid10 on centos 5
Eli Stair wrote: You shouldn't need to build a new kernel, just extract the SRPM for the initial install (CentOS 5, no updated kernels), use the config for the appropriate kernel (SMP, UP, i386/x86_64), enable the raid10 module and do a 'make modules'. You may need to do a minor amount of tweaking in the installer image to include this, but nothing serious. Alternately, just building a driver disk with the module and source it in the install. Interesting that it's not enabled in the installer image, because it's present in a fully-booted system... space limitations? /eli It is not present in a fully booted system for me either. Are you running centos 5? How would I make a driver disk? I'm not very familiar with this. Russ - 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: raid10 on centos 5
You shouldn't need to build a new kernel, just extract the SRPM for the initial install (CentOS 5, no updated kernels), use the config for the appropriate kernel (SMP, UP, i386/x86_64), enable the raid10 module and do a 'make modules'. You may need to do a minor amount of tweaking in the installer image to include this, but nothing serious. Alternately, just building a driver disk with the module and source it in the install. Interesting that it's not enabled in the installer image, because it's present in a fully-booted system... space limitations? /eli Ruslan Sivak wrote: Guy Watkins wrote: } -Original Message- } From: [EMAIL PROTECTED] [mailto:linux-raid- } [EMAIL PROTECTED] On Behalf Of Ruslan Sivak } Sent: Friday, May 04, 2007 12:22 PM } To: linux-raid@vger.kernel.org } Subject: raid10 on centos 5 } } I am trying to set up raid 10 and so far with no luck. I have 4 drives, } and Anaconda will not let me do raid 10. mdadm doesn't have the raid 10 } personality loaded. When I create the array manually like so: } } 2 drives in /dev/md11 as raid1 } 2 drives in /dev/md12 as raid1 } md11 and md12 in /dev/md10 as raid0 } } Everything looks fine from the shell, but anaconda only sees md11 and } md12. } } The only choice I see is to set up LVM over md11 and md12. Is this } really raid10? } } Russ You are making a RAID1+RAID0 array. Try making a real RAID10 array with 4 drives. This way you would only have 1 array with 4 drives. From the mdadm man page: Currently, Linux supports LINEAR md devices, RAID0 (striping), RAID1 (mirroring), RAID4, RAID5, RAID6, RAID10, MULTIPATH, and FAULTY. Notice RAID10 is listed, use that. Man mdadm for more info. However, I would (and do) use RAID6. With RAID6 any 2 disks can fail without data loss. With RAID1+RAID0, any one disk can fail, a second failure has a 1 in 3 chance of vast data loss. I hope this helps, Guy - Guy, That's what I've been trying to do. Unfortunatelly, my distro, CentOS 5 (based on RHEL 5, I believe), does not have the RAID10 personality in the kernel. I guess I would have to compile my own kernel and load the module through a driver disk. Would that work? Are there some instructions somewhere I can follow? Russ - 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: raid10 on centos 5
} -Original Message- } From: Ruslan Sivak [mailto:[EMAIL PROTECTED] } Sent: Friday, May 04, 2007 7:22 PM } To: Guy Watkins } Cc: linux-raid@vger.kernel.org } Subject: Re: raid10 on centos 5 } } Guy Watkins wrote: } } -Original Message- } } From: [EMAIL PROTECTED] [mailto:linux-raid- } } [EMAIL PROTECTED] On Behalf Of Ruslan Sivak } } Sent: Friday, May 04, 2007 12:22 PM } } To: linux-raid@vger.kernel.org } } Subject: raid10 on centos 5 } } } } I am trying to set up raid 10 and so far with no luck. I have 4 } drives, } } and Anaconda will not let me do raid 10. mdadm doesn't have the raid } 10 } } personality loaded. When I create the array manually like so: } } } } 2 drives in /dev/md11 as raid1 } } 2 drives in /dev/md12 as raid1 } } md11 and md12 in /dev/md10 as raid0 } } } } Everything looks fine from the shell, but anaconda only sees md11 and } } md12. } } } } The only choice I see is to set up LVM over md11 and md12. Is this } } really raid10? } } } } Russ } } You are making a RAID1+RAID0 array. } Try making a real RAID10 array with 4 drives. This way you would only } have } 1 array with 4 drives. } } From the mdadm man page: } Currently, Linux supports LINEAR md devices, RAID0 (striping), RAID1 } (mirroring), RAID4, RAID5, RAID6, RAID10, MULTIPATH, and FAULTY. } } Notice RAID10 is listed, use that. Man mdadm for more info. } } However, I would (and do) use RAID6. With RAID6 any 2 disks can fail } without data loss. With RAID1+RAID0, any one disk can fail, a second } failure has a 1 in 3 chance of vast data loss. } } I hope this helps, } Guy } } - } } } } Guy, } } That's what I've been trying to do. Unfortunatelly, my distro, CentOS 5 } (based on RHEL 5, I believe), does not have the RAID10 personality in } the kernel. I guess I would have to compile my own kernel and load the } module through a driver disk. Would that work? Are there some } instructions somewhere I can follow? } } Russ I don't know how to make a driver disk. Also not much on making modules. From what I know, linux only loads the RAID modules it needs. My system does not have raid0 or raid10 loaded. But both loaded when I used modprobe. I have FC6, upgraded from FC5 using yum, so maybe not 100% FC6. Anyway, you were not making a RAID10 array. You were making 2 RAID1 arrays and then 1 RAID0 array. That does not need the RAID10 module (AFAIK). If I recall, there is an issue of nesting arrays like you were doing. The problem was related to auto starting them. But I don't recall any details, and maybe it has been corrected. Guy - 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
