Re: RAID5 drive failure, please verify my commands
Gerd Knops wrote: Hello all, One of the dreaded Maxtor SATA drives in my RAID5 failed, after just 3 months of light use. Anyhow I neither have the disk capacity nor the money to buy it to make a backup. To make sure I do it correctly, could you folks please double-check my intended course of action? I would really appreciate that. Gerd, If you've got a credit card you can get Maxtor to send out a replacement without having to pull the failed drive. I've done this several times :) (by Maxtor drives!) R. -- http://robinbowes.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: RAID5 drive failure, please verify my commands
Mike Hardy wrote: Gerd Knops wrote: Hello all, One of the dreaded Maxtor SATA drives in my RAID5 failed, after just 3 months of light use. Anyhow I neither have the disk capacity nor the money to buy it to make a backup. To make sure I do it correctly, could you folks please double-check my intended course of action? I would really appreciate that. Failed how? I have tons and tons of Maxtor drives in service, and only one actually had a complete failure (verified by their utility, which is present on some bootable CD I got called UltimateBootDisk). Mike, When one of my drives fails I test it with the Maxtor Powermax tool - it's this tool that is confirming that the drive(s) is(are) dieing. The only saving grace is the three-year warranty. R. -- http://robinbowes.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: migrating raid-1 to different drive geometry ?
Neil Brown wrote: If you are using a recent 2.6 kernel and mdadm 1.8.0, you can grow the array with mdadm --grow /dev/mdX --size=max Neil, Is this just for RAID1? OR will it work for RAID5 too? R. -- http://robinbowes.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: Broken harddisk
Luca Berra wrote: On Tue, Feb 01, 2005 at 03:02:54PM +, Robin Bowes wrote: True enough. However, until SMART support makes it into linux SATA drivers I'm pretty much stuck with dd! http://www.kernel.org/pub/linux/kernel/people/jgarzik/libata/ I avoid patching kernels, preferring to use the stock Fedora releases. Perhaps I should re-phrase the above statement to read until the Fedora Core 3 kernel includes SMART support in libata ... :) Actually, I'm running 2.6.10 - how can I tell if SMART support is included in libata? R. -- http://robinbowes.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
Joys of spare disks!
Hi, I run a RAID5 array built from six 250GB Maxtor Maxline II SATA disks. After having several problems with Maxtor disks I decided to use a spare disk, i.e. 5+1 spare. Well, *another* disk failed last week. The spare disk was brought into play seamlessly: [EMAIL PROTECTED] ~]# mdadm --detail /dev/md5 /dev/md5: Version : 00.90.01 Creation Time : Thu Jul 29 21:41:38 2004 Raid Level : raid5 Array Size : 974566400 (929.42 GiB 997.96 GB) Device Size : 243641600 (232.35 GiB 249.49 GB) Raid Devices : 5 Total Devices : 6 Preferred Minor : 5 Persistence : Superblock is persistent Update Time : Mon Feb 28 14:00:54 2005 State : clean Active Devices : 5 Working Devices : 5 Failed Devices : 1 Spare Devices : 0 Layout : left-symmetric Chunk Size : 128K UUID : a4bbcd09:5e178c5b:3bf8bd45:8c31d2a1 Events : 0.6941488 Number Major Minor RaidDevice State 0 820 active sync /dev/sda2 1 8 181 active sync /dev/sdb2 2 8 342 active sync /dev/sdc2 3 8 823 active sync /dev/sdf2 4 8 664 active sync /dev/sde2 5 8 50- faulty /dev/sdd2 I've done a quick test of /dev/sdd2: [EMAIL PROTECTED] ~]# dd if=/dev/sdd2 of=/dev/null bs=64k dd: reading `/dev/sdd2': Input/output error 50921+1 records in 50921+1 records out So, I guess it's time to raise another return with Maxtor sigh. /dev/sdd1 is used in /dev/md0. So, just to confirm, is this what I need to do to remove bad disk/add new disk: Remove faulty partition: mdadm --manage /dev/md5 --remove /dev/sdd2 Remove good from RAID1 array: mdadm --manage /dev/md0 --fail /dev/sdd1 mdadm --manage /dev/md0 --remove /dev/sdd1 [pull out bad disk, install replacement] Partition new disk (will be /dev/sdd) (All six disks are partitioned the same): fdisk -l /dev/sda | fdisk /dev/sdd (I seem to remember having a problem with this when I did it last time. Something about a bug in fdisk that won't partition brand new new disks correctly? Or was it sfdisk?) Add new partitions to arrays: mdadm --manage /dev/md0 --add /dev/sdd1 mdadm --manage /dev/md5 --add /dev/sdd2 Thanks, R. -- http://robinbowes.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: non-optimal RAID 5 performance with 8 drive array
Nicola Fankhauser wrote: see [3] for a description of what I did and more details. Hi Nicola, I read your description with interest. I thought I'd try some speed tests myself but dd doesn't seem to work the same for me (on FC3). Here's what I get: [EMAIL PROTECTED] test]# dd if=/dev/zero of=/home/test/test.tmp bs=4096 count=10 10+0 records in 10+0 records out Notice there is no timing information. For the read test: [EMAIL PROTECTED] test]# dd of=/dev/null if=/home/test/test.tmp bs=4096 10+0 records in 10+0 records out Again, no timing information. Anyone know if this is a quirk of the FC3 version of dd? R. -- http://robinbowes.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: new array not starting
Robin Bowes wrote: If I try to start the array manually: # mdadm --assemble --auto=yes /dev/md2 /dev/hdc /dev/hdd /dev/hde /dev/hdf /dev/hdg /dev/hdh /dev/hdi /dev/hdj mdadm: cannot open device /dev/hdc: No such file or directory mdadm: /dev/hdc has no superblock - assembly aborted What's going on here? No superblock? Doesn't that get written when the array is created? Am I doing this right? SATA disks? hdc? Duh! This worked: # mdadm --assemble --auto=yes /dev/md2 /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg /dev/sdh /dev/sdi /dev/sdj mdadm: /dev/md2 has been started with 8 drives. However, I'm not sure why it didn't start automatically at boot. Do I need to put it in /etc/mdadm.conf for it to star automatically? I thought md start all arrays it found at a start up? R. - 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: new array not starting
Robin Bowes wrote: This worked: # mdadm --assemble --auto=yes /dev/md2 /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg /dev/sdh /dev/sdi /dev/sdj mdadm: /dev/md2 has been started with 8 drives. However, I'm not sure why it didn't start automatically at boot. Do I need to put it in /etc/mdadm.conf for it to star automatically? I thought md start all arrays it found at a start up? OK, I put /dev/md2 in /etc/mdadm.conf and it didn't make any difference. This is mdadm.conf (uuids are on same line as ARRAY): DEVICE partitions ARRAY /dev/md1 level=raid1 num-devices=2 uuid=300c1309:53d26470:64ac883f:2e3de671 ARRAY /dev/md0 level=raid1 num-devices=2 uuid=89649359:d89365a6:0192407d:e0e399a3 ARRAY /dev/md2 level=raid6 num-devices=8 UUID=68c2ea69:a30c3cb0:9af9f0b8:1300276b I saw an error fly by as the server was booting saying /dev/md2 not found. Do I need to create this device manually? R. - 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: new array not starting
Robin Bowes wrote: Robin Bowes wrote: This worked: # mdadm --assemble --auto=yes /dev/md2 /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg /dev/sdh /dev/sdi /dev/sdj mdadm: /dev/md2 has been started with 8 drives. However, I'm not sure why it didn't start automatically at boot. Do I need to put it in /etc/mdadm.conf for it to star automatically? I thought md start all arrays it found at a start up? OK, I put /dev/md2 in /etc/mdadm.conf and it didn't make any difference. This is mdadm.conf (uuids are on same line as ARRAY): DEVICE partitions ARRAY /dev/md1 level=raid1 num-devices=2 uuid=300c1309:53d26470:64ac883f:2e3de671 ARRAY /dev/md0 level=raid1 num-devices=2 uuid=89649359:d89365a6:0192407d:e0e399a3 ARRAY /dev/md2 level=raid6 num-devices=8 UUID=68c2ea69:a30c3cb0:9af9f0b8:1300276b I saw an error fly by as the server was booting saying /dev/md2 not found. Do I need to create this device manually? Well, at the risk of having a complete conversation with myself, I've created partitions of type fd on each disk and re-created the array out of the partitions instead of the whole disk. mdadm --create /dev/md2 --auto=yes --raid-devices=8 --level=6 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1 /dev/sdg1 /dev/sdh1 /dev/sdi1 /dev/sdj1 I'm hoping this will enable the array to be auto-detected and started at boot. R. - 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: new array not starting
Robin Bowes wrote: Well, at the risk of having a complete conversation with myself, I've created partitions of type fd on each disk and re-created the array out of the partitions instead of the whole disk. mdadm --create /dev/md2 --auto=yes --raid-devices=8 --level=6 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1 /dev/sdg1 /dev/sdh1 /dev/sdi1 /dev/sdj1 I'm hoping this will enable the array to be auto-detected and started at boot. That seemed to do the trick. I left the array to build overnight and rebooted this morning, and /dev/md2 started normally. R. - 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: raid5 software vs hardware: parity calculations?
Bill Davidsen wrote: There have been several recent threads on the list regarding software RAID-5 performance. The reference might be updated to reflect the poor write performance of RAID-5 until/unless significant tuning is done. Read that as tuning obscure parameters and throwing a lot of memory into stripe cache. The reasons for hardware RAID should include performance of RAID-5 writes is usually much better than software RAID-5 with default tuning. Could you point me at a source of documentation describing how to perform such tuning? Specifically, I have 8x500GB WD STAT drives on a Supermicro PCI-X 8-port SATA card configured as a single RAID6 array (~3TB available space) Thanks, R. - 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: raid5 software vs hardware: parity calculations?
Bill Davidsen wrote: Robin Bowes wrote: Bill Davidsen wrote: There have been several recent threads on the list regarding software RAID-5 performance. The reference might be updated to reflect the poor write performance of RAID-5 until/unless significant tuning is done. Read that as tuning obscure parameters and throwing a lot of memory into stripe cache. The reasons for hardware RAID should include performance of RAID-5 writes is usually much better than software RAID-5 with default tuning. Could you point me at a source of documentation describing how to perform such tuning? No. There has been a lot of discussion of this topic on this list, and a trip through the archives of the last 60 days or so will let you pull out a number of tuning tips which allow very good performance. My concern was writing large blocks of data, 1MB per write, to RAID-5, and didn't involve the overhead of small blocks at all, that leads through other code and behavior. Actually Bill, I'm running RAID6 (my mistake for not mentioning it explicitly before) - I found some material relating to RAID5 but nothing on RAID6. Are the concepts similar, or is RAID6 a different beast altogether? Specifically, I have 8x500GB WD STAT drives on a Supermicro PCI-X 8-port SATA card configured as a single RAID6 array (~3TB available space) No hot spare(s)? I'm running RAID6 instead of RAID5+1 - I've had a couple of instances where a drive has failed in a RAID5+1 array and a second has failed during the rebuild after the hot-spare had kicked in. R. - 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
