Re: RAID 5 performance issue.
Andrew Clayton wrote: On Thu, 4 Oct 2007 10:39:09 -0400 (EDT), Justin Piszcz wrote: What type (make/model) of the drives? The drives are 250GB Hitachi Deskstar 7K250 series ATA-6 UDMA/100 A couple of things: 1. I thought you had SATA drives 2. ATA-6 would be UDMA/133 The SATA-1 versions of the 7K250's did not have NCQ. The SATA-2 versions do have NCQ. If you do have SATA drives, are they SATA-1 or SATA-2? Steve - 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: RAID 5 performance issue.
Steve Cousins wrote: A couple of things: 1. I thought you had SATA drives 2. ATA-6 would be UDMA/133 Number 2 is not correct. Sorry about that. Steve - 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: Linux Software RAID a bit of a weakness?
Colin Simpson wrote: Hi, We had a small server here that was configured with a RAID 1 mirror, using two IDE disks. Last week one of the drives failed in this. So we replaced the drive and set the array to rebuild. The "good" disk then found a bad block and the mirror failed. Now I presume that the "good" disk must have had an underlying bad block in either unallocated space or a file I never access. Now as RAID works at the block level you only ever see this on an array rebuild when it's often catastrophic. Is this a bit of a flaw? I know there is the definite probability of two drives failing within a short period of time. But this is a bit different as it's the probability of two drives failing but over a much larger time scale if one of the flaws is hidden in unallocated space (maybe a dirt particle finds it's way onto the surface or something). This would make RAID buy you a lot less in reliability, I'd have thought. I seem to remember seeing in the log file for a Dell perc something about scavenging for bad blocks. Do hardware RAID systems have a mechanism that at times of low activity search the disks for bad blocks to help guard against this sort of failure (so a disk error is reported early)? On Software RAID, I was thinking apart from a three way mirror, which I don't think is at present supported. Is there any merit in say, cat'ing the whole disk devices to /dev/null every so often to check that the whole surface is readable (I presume just reading the raw device won't upset thing, don't worry I don't plan on trying it on a production system). Any thoughts? As I presume people have thought of this before and I must be missing something. Yes, this is an important thing to keep on top of, both for hardware RAID and software RAID. For md: echo check > /sys/block/md0/md/sync_action This should be done regularly. I have cron do it once a week. Check out: http://neil.brown.name/blog/20050727141521-002 Good luck, Steve -- ______ Steve Cousins, Ocean Modeling GroupEmail: [EMAIL PROTECTED] Marine Sciences, 452 Aubert Hall http://rocky.umeoce.maine.edu Univ. of Maine, Orono, ME 04469Phone: (207) 581-4302 - 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: Changing chunk size
Bill Davidsen wrote: I'm sure "slow" is a relative term, compared to backing up TBs of data and trying to restore them. Not to mention the lack of inexpensive TB size backup media. That's totally unavailable at the moment, I'll live with what I have, thanks. You don't backup your RAID arrays? Yikes! For certain data this would be fine (data that you can recreate easily) but it sounds like this isn't the case for you otherwise you'd just wipe the array and recreate the data. There are other modes of failure than just the drives themselves (file system corruption for instance) so it is wise to do backups, even on "redundant" systems. Good luck, Steve -- __________ Steve Cousins, Ocean Modeling GroupEmail: [EMAIL PROTECTED] Marine Sciences, 452 Aubert Hall http://rocky.umeoce.maine.edu Univ. of Maine, Orono, ME 04469Phone: (207) 581-4302 - 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: Raid on USB flash disk
Arne Jansen wrote: > > The main reason why I'm trying this weird setup is that the USB > drive is always enumerated last in my kernel, and I want to boot > from it. That means every time I add a disk or remove one I have > to edit grub.conf and fstab. Very inconvenient. So my idea was > to create a single device md on it and leave it to the autodetection > to find the device. So I never have to edit /etc/fstab again for > a simple hardware change and I'm independent of any enumeration > changes in future kernel releases. > > But unfortunately it doesn't work :-( Sorry not to answer your main question but why not use labels in your USB device partitions and use the labels in your fstab. This will make it so it doesn't matter which dev file it uses. Steve - 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: change strip_cache_size freeze the whole raid
Justin Piszcz wrote: Yes, I noticed this bug too, if you change it too many times or change it at the 'wrong' time, it hangs up when you echo numbr > /proc/stripe_cache_size. Basically don't run it more than once and don't run it at the 'wrong' time and it works. Not sure where the bug lies, but yeah I've seen that on 3 different machines! Can you tell us when the "right" time is or maybe what the "wrong" time is? Also, is this kernel specific? Does it (increasing stripe_cache_size) work with RAID6 too? Thanks, Steve -- __________ Steve Cousins, Ocean Modeling GroupEmail: [EMAIL PROTECTED] Marine Sciences, 452 Aubert Hall http://rocky.umeoce.maine.edu Univ. of Maine, Orono, ME 04469Phone: (207) 581-4302 - 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: bad performance on RAID 5
Sevrin Robstad wrote: I'm suffering from bad performance on my RAID5. a "echo check >/sys/block/md0/md/sync_action" gives a speed at only about 5000K/sec , and HIGH load average : What do you get when you try something like: time dd if=/dev/zero of=/mount-point/test.dat bs=1024k count=1024 where /mount-point is where /dev/md0 is mounted. This will create a 1 GiB file and it will tell you how long it takes to create it. Also, I'd try running Bonnie++ on it to see what the different performance values are. I don't know a lot about the md sync process but I remember having my sync action stuck at a low value at one point and it didn't have anything to do with the performance of the RAID array in general. Steve # uptime 20:03:55 up 8 days, 19:55, 1 user, load average: 11.70, 4.04, 1.52 kernel is 2.6.18.1.2257.fc5 mdadm is v2.5.5 the system consist of an athlon XP1,2GHz and two Sil3114 4port S-ATA PCI cards with a total of 6 250gb S-ATA drives connected. [EMAIL PROTECTED] ~]# mdadm --detail /dev/md0 /dev/md0: Version : 00.90.03 Creation Time : Tue Dec 5 00:33:01 2006 Raid Level : raid5 Array Size : 1218931200 (1162.46 GiB 1248.19 GB) Device Size : 243786240 (232.49 GiB 249.64 GB) Raid Devices : 6 Total Devices : 6 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Wed Jan 17 23:14:39 2007 State : clean Active Devices : 6 Working Devices : 6 Failed Devices : 0 Spare Devices : 0 Layout : left-symmetric Chunk Size : 256K UUID : 27dce477:6f45d11b:77377d08:732fa0e6 Events : 0.58 Number Major Minor RaidDevice State 0 810 active sync /dev/sda1 1 8 171 active sync /dev/sdb1 2 8 332 active sync /dev/sdc1 3 8 493 active sync /dev/sdd1 4 8 654 active sync /dev/sde1 5 8 815 active sync /dev/sdf1 [EMAIL PROTECTED] ~]# Sevrin - 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 -- ______ Steve Cousins, Ocean Modeling GroupEmail: [EMAIL PROTECTED] Marine Sciences, 452 Aubert Hall http://rocky.umeoce.maine.edu Univ. of Maine, Orono, ME 04469Phone: (207) 581-4302 - 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: Correct way to create multiple RAID volumes with hot-spare?
Ruth Ivimey-Cook wrote: Steve, The recent "Messed up creating new array..." thread has someone who started by using the whole drives but she now wants to use partitions because the array is not starting automatically on boot (I think that was the symptom). I'm guessing this is because there is no partigion ID of "fd" since there isn't even a partition. Yes, that's right. Thanks Ruth. Neil (or others), what is the recommended way to have the array start up if you use whole drives instead of partitions? Do you put mdadm -A etc. in rc.local? Thanks, Steve - 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: access array from knoppix
Dexter Filmore wrote: When running Knoppix on my file server, I can't mount /dev/md0 simply because it isn't there. Am I guessing right that I need to recreate the array? How do I gather the necessary parameters? From the man page: mdadm -Ac partitions -m 0 /dev/md0 This will "assemble" the array, as opposed to "create". It says to look in /proc/partitions for viable partitions and then assemble the array with devices that have a superblock minor number of 0. Once done, /dev/md0 will exist. Tuomas was not being a "wisecracker". His advice was valid. Steve - 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: Correct way to create multiple RAID volumes with hot-spare?
Neil Brown wrote: On Tuesday August 22, [EMAIL PROTECTED] wrote: >> Maybe I shouldn't be splitting the drives up into partitions. I did this due to issues with volumes greater than 2TB. Maybe this isn't an issue anymore and I should just rebuild the array from scratch with single partitions. Or should there even be partitions? Should I just use /dev/sd[abcdefghijk] ? I tend to just use whole drives, but your set up should work fine. md/raid isn't limited to 2TB, but some filesystems might have size issues (though i think even ext2 gots to at least 8 TB these days). The recent "Messed up creating new array..." thread has someone who started by using the whole drives but she now wants to use partitions because the array is not starting automatically on boot (I think that was the symptom). I'm guessing this is because there is no partigion ID of "fd" since there isn't even a partition. I'm on the verge of re-doing this array with 11 full drives (/dev/sd? as opposed to /dev/sd?1 and /dev/sd?2). Will I have the same problems with booting? I like the idea of not having to partition the drives but not if it is going to cause hassles. I realize that there could be a potential problem if I need to replace a drive with a slightly different model that is slightly smaller. Thanks, Steve -- ______ Steve Cousins, Ocean Modeling GroupEmail: [EMAIL PROTECTED] Marine Sciences, 452 Aubert Hall http://rocky.umeoce.maine.edu Univ. of Maine, Orono, ME 04469Phone: (207) 581-4302 - 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: raidhotadd works, mdadm --add doesn't
Leon Avery wrote: I've been using RAID for a long time, but have been using the old raidtools. Having just discovered mdadm, I want to switch, but I'm having trouble. I'm trying to figure out how to use mdadm to replace a failed disk. Here is my /proc/mdstat: Personalities : [linear] [raid1] read_ahead 1024 sectors md5 : active linear md3[1] md4[0] 1024504832 blocks 64k rounding md4 : active raid1 hdf5[0] hdh5[1] 731808832 blocks [2/2] [UU] md3 : active raid1 hde5[0] hdg5[1] 292696128 blocks [2/2] [UU] md2 : active raid1 hda5[0] hdc5[1] 48339456 blocks [2/2] [UU] md0 : active raid1 hda3[0] hdc3[1] 9765376 blocks [2/2] [UU] unused devices: The relevant parts are md0 and md2. Physical disk hda failed, which left md0 and md2 running in degraded mode. Having an old spare used disk sitting on the shelf, I plugged it in, repartitioned it, and said mdadm --add /dev/md0 /dev/hda3 I think the thing to do is to list the md device before the --add : mdadm /dev/md0 --add /dev/hda3 I use the -a form and do: mdadm /dev/md0 -a /dev/hda3 Steve - 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: Care and feeding of RAID?
Rev. Jeffrey Paul wrote: On Tue, Sep 05, 2006 at 11:03:45AM -0400, Steve Cousins wrote: These are SATA drives and except for the one machine that has a 3Ware 8506 card in it I haven't been able to get SMART programs to do anything with these drives. How do others deal with this? I use the tw_cli program to check up on my 3ware stuff. Hi Jeffrey, Thanks. I use tw_cli too and I have scripted a check to see if it degrades but this doesn't help with checking for disk problems before they happen which SMART should help with. As it happens, smartctl works with 3Ware SATA drives. It is my other SATA drives that I'm unable to monitor. Steve It took me quite a bit of time to figure that one out. I don't have any automated monitoring set up, but it'd be simple enough to script. I check on the array every so often and run a verify every few months to see if it kicks a disk out (it hasn't yet). 0 [EMAIL PROTECTED]:~# tw_cli //datavibe> info Ctl ModelPorts Drives Units NotOpt RRate VRate BBU c08006-2LP 2 21 02 - - //datavibe> info c0 Unit UnitType Status %Cmpl Stripe Size(GB) Cache AVerify IgnECC -- u0RAID-1OK - - 232.885 ON -- Port Status Unit SizeBlocksSerial --- p0 OK u0 232.88 GB 488397168 WD-WMAL718611 p1 OK u0 232.88 GB 488397168 WD-WMAL718619 //datavibe> -j -- ______ Steve Cousins, Ocean Modeling GroupEmail: [EMAIL PROTECTED] Marine Sciences, 452 Aubert Hall http://rocky.umeoce.maine.edu Univ. of Maine, Orono, ME 04469Phone: (207) 581-4302 - 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: Care and feeding of RAID?
Benjamin Schieder wrote: On 05.09.2006 11:03:45, Steve Cousins wrote: Would people be willing to list their setup? Including such things as mdadm.conf file, crontab -l, plus scripts that they use to check the smart data and the array, mdadm daemon parameters and anything else that is relevant to checking and maintaining an array? Personally, I use this script from cron: http://shellscripts.org/project/hdtest Hi Benjamin, I am checking this out and I see that you are the writer of this script. I'm getting errors when it comes to lines 76 and 86-90 about the arithmetic symbols. This is on a Fedora Core 5 system with bash version 3.1.7(1). I weeded out the smartctl command and tried it manually with no luck on my SATA /dev/sd? drives. What do you (or others) recommend for SATA drives? Thanks, Steve - 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: Care and feeding of RAID?
Gordon Henderson wrote: On Tue, 5 Sep 2006, Paul Waldo wrote: Hi all, I have a RAID6 array and I wondering about care and feeding instructions :-) Here is what I currently do: - daily incremental and weekly full backups to a separate machine - run smartd tests (short once a day, long once a week) - check the raid for bad blocks every week What else can I do make sure the array keeps humming? Thanks in advance! Stop fiddling with it :) I run similar stuff, but don't forget running mdadm in daemon mode to send you an email should a drive fail. I also check each device individually, rather than the array although I don't know the value of doing this over the SMART tests on modern drives though... Would people be willing to list their setup? Including such things as mdadm.conf file, crontab -l, plus scripts that they use to check the smart data and the array, mdadm daemon parameters and anything else that is relevant to checking and maintaining an array? I'm running the mdmonitor script at startup and a sample mdadm.conf (one of 3 machines) looks like: MAILADDR [EMAIL PROTECTED] ARRAY /dev/md0 level=raid5 num-devices=3 UUID=39d07542:f3c97e69:fbb63d9d:64a052d3 devices=/dev/sdb1,/dev/sdc1,/dev/sdd1 These are SATA drives and except for the one machine that has a 3Ware 8506 card in it I haven't been able to get SMART programs to do anything with these drives. How do others deal with this? Thanks, Steve - 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: Correct way to create multiple RAID volumes with hot-spare?
Neil Brown wrote: > On Tuesday August 22, [EMAIL PROTECTED] wrote: > > Hi, > > > > I have a set of 11 500 GB drives. Currently each has two 250 GB > > partitions (/dev/sd?1 and /dev/sd?2). I have two RAID6 arrays set up, > > each with 10 drives and then I wanted the 11th drive to be a hot-spare. > > When I originally created the array I used mdadm and only specified > > the use of 10 drives since the 11th one wasn't even a thought at the > > time (I didn't think I could get an 11th drive in the case). Now I can > > manually add in the 11th drive partitions into each of the arrays and > > they show up as a spares but on reboot they aren't part of the set > > anymore. I have added them into /etc/mdadm.conf and the partition type > > is set to be Software RAID (fd). > > Can you show us exactly what /etc/mdadm.conf contains? > And what kernel messages do you get when it assembled the array but > leaves off the spare? > Here is mdadm.conf: DEVICE /dev/sd[abcdefghijk]* ARRAY /dev/md0 level=raid6 num-devices=10 spares=1 UUID=70c02805:0a324ae8:679fc224:3112a95f devices=/dev/sda1,/dev/sdb1,/dev/sdc1,/dev/sdd1,/dev/sde1,/dev/sdf1,/dev/sdg1,/dev/sdh1,/dev/sdi1,/dev/sdj1,/dev/sdk1 ARRAY /dev/md1 level=raid6 num-devices=10 spares=1 UUID=87692745:1a99d67a:462b8426:4e181b2e devices=/dev/sda2,/dev/sdb2,/dev/sdc2,/dev/sdd2,/dev/sde2,/dev/sdf2,/dev/sdg2,/dev/sdh2,/dev/sdi2,/dev/sdj2,/dev/sdk2 Below is the info from /var/log/messages. This is a listing of when two partitions from each array were left off. It also is an example of when it doesn't list the spare. If you want me a newer listing from when the array builds correctly but doesn't have a spare let me know. What I hadn't really looked at before is the lines that say: sdk1 has different UUID to sdk2 etc. Of course it doesn't. Maybe this isn't part of the problem Aug 21 18:56:09 juno mdmonitor: mdadm shutdown succeeded Aug 21 19:01:03 juno mdmonitor: mdadm startup succeeded Aug 21 19:01:04 juno mdmonitor: mdadm succeeded Aug 21 19:01:06 juno kernel: md: md driver 0.90.3 MAX_MD_DEVS=256, MD_SB_DISKS=27 Aug 21 19:01:06 juno kernel: md: bitmap version 4.39 Aug 21 19:01:06 juno kernel: md: raid6 personality registered for level 6 Aug 21 19:01:06 juno kernel: md: Autodetecting RAID arrays. Aug 21 19:01:06 juno kernel: md: autorun ... Aug 21 19:01:06 juno kernel: md: considering sdk2 ... Aug 21 19:01:06 juno kernel: md: adding sdk2 ... Aug 21 19:01:06 juno kernel: md: sdk1 has different UUID to sdk2 Aug 21 19:01:06 juno kernel: md: adding sdj2 ... Aug 21 19:01:06 juno kernel: md: sdj1 has different UUID to sdk2 Aug 21 19:01:06 juno kernel: md: adding sdi2 ... Aug 21 19:01:06 juno kernel: md: sdi1 has different UUID to sdk2 Aug 21 19:01:06 juno kernel: md: adding sdh2 ... Aug 21 19:01:06 juno kernel: md: sdh1 has different UUID to sdk2 Aug 21 19:01:06 juno kernel: md: adding sdg2 ... Aug 21 19:01:06 juno kernel: md: sdg1 has different UUID to sdk2 Aug 21 19:01:06 juno kernel: md: adding sdf2 ... Aug 21 19:01:06 juno kernel: md: sdf1 has different UUID to sdk2 Aug 21 19:01:06 juno kernel: md: adding sde2 ... Aug 21 19:01:06 juno kernel: md: sde1 has different UUID to sdk2 Aug 21 19:01:07 juno kernel: md: adding sdd2 ... Aug 21 19:01:07 juno kernel: md: sdd1 has different UUID to sdk2 Aug 21 19:01:07 juno kernel: md: adding sdc2 ... Aug 21 19:01:07 juno kernel: md: sdc1 has different UUID to sdk2 Aug 21 19:01:07 juno kernel: md: adding sdb2 ... Aug 21 19:01:07 juno kernel: md: sdb1 has different UUID to sdk2 Aug 21 19:01:07 juno kernel: md: adding sda2 ... Aug 21 19:01:07 juno kernel: md: sda1 has different UUID to sdk2 Aug 21 19:01:07 juno kernel: md: created md1 Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: bind Aug 21 19:01:07 juno kernel: md: export_rdev(sdk2) Aug 21 19:01:07 juno kernel: md: running: Aug 21 19:01:07 juno kernel: md: kicking non-fresh sdi2 from array! Aug 21 19:01:07 juno kernel: md: unbind Aug 21 19:01:07 juno kernel: md: export_rdev(sdi2) Aug 21 19:01:07 juno kernel: md: kicking non-fresh sdb2 from array! Aug 21 19:01:07 juno kernel: md: unbind Aug 21 19:01:07 juno kernel: md: export_rdev(sdb2) Aug 21 19:01:07 juno kernel: raid6: allocated 10568kB for md1 Aug 21 19:01:07 juno kernel: raid6: raid level 6 set md1 active with 8 out of 10 devices, algorithm 2 Aug 21 19:01:07 juno kernel: md: considering sdk1 ... Aug 21 19:01:07 juno kernel: md: adding sdk1 ... Aug 21 19:01:07 juno kernel: md: adding sdj1 ... Aug 21 19:01:07 juno kernel: md: adding sdi1 ... Aug 21 19:01:07 juno kernel: md: adding sdh1 ... Aug 21 19:01:07 juno kernel: md: adding sdg1 ... Aug 21 19:01:07 juno kernel: md: adding
Re: Correct way to create multiple RAID volumes with hot-spare?
Joshua Baker-LePain wrote: > On Wed, 23 Aug 2006 at 6:34am, Justin Piszcz wrote > > > On Tue, 22 Aug 2006, Steve Cousins wrote: > > > >> As for system information, it is (was) a Dual Opteron with CentOS 4.3 (now > >> I'm putting FC5 on it as I write) with a 3Ware 8506-12 SATA RAID card that > >> I am using in JBOD mode so I could do software RAID6. > >> > > > > If you are using SW RAID, there is no 2TB limit. > > Ditto for more recent HW RAIDs. *However*, there are other considerations > when dealing with >2TiB devices. E.g. you can't boot from them. > You are both correct. When I said "due to issues with volumes greater than 2TB" I should have indicated that they were more to do with my issues and/or our environment. I probably wasn't persistent enough with it. I now have a DAS box with >2TB volumes and it is working fine so I should probably start over using no partions and see how it goes. Thanks, Steve - 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
Correct way to create multiple RAID volumes with hot-spare?
Hi, I have a set of 11 500 GB drives. Currently each has two 250 GB partitions (/dev/sd?1 and /dev/sd?2). I have two RAID6 arrays set up, each with 10 drives and then I wanted the 11th drive to be a hot-spare. When I originally created the array I used mdadm and only specified the use of 10 drives since the 11th one wasn't even a thought at the time (I didn't think I could get an 11th drive in the case). Now I can manually add in the 11th drive partitions into each of the arrays and they show up as a spares but on reboot they aren't part of the set anymore. I have added them into /etc/mdadm.conf and the partition type is set to be Software RAID (fd). Maybe I shouldn't be splitting the drives up into partitions. I did this due to issues with volumes greater than 2TB. Maybe this isn't an issue anymore and I should just rebuild the array from scratch with single partitions. Or should there even be partitions? Should I just use /dev/sd[abcdefghijk] ? On a side note, maybe for another thread, the arrays work great until a reboot (using 'shutdown' or 'reboot' and they seem to be shutting down the md system correctly). Sometimes one or even two (yikes!) partitions in each array go offline and I have to mdadm /dev/md0 -a /dev/sdx1 it back in. Do others experience this regularly with RAID6? Is RAID6 not ready for prime time? As for system information, it is (was) a Dual Opteron with CentOS 4.3 (now I'm putting FC5 on it as I write) with a 3Ware 8506-12 SATA RAID card that I am using in JBOD mode so I could do software RAID6. Thanks for your help. Steve -- __________ Steve Cousins, Ocean Modeling GroupEmail: [EMAIL PROTECTED] Marine Sciences, 452 Aubert Hall http://rocky.umeoce.maine.edu Univ. of Maine, Orono, ME 04469Phone: (207) 581-4302 - 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
