RAID5 Array Setup on Gentoo using mdadm and recovery
RAID is all set up and working! Finally! Very happy with it.
Sorry, this is going to look a lot of rubbish to most people, but here’s how I got my RAID to work and the diag output!
I’m pretty sure it’d be useful to someone.
If you don’t find the below interesting, I think you’d like this at least:
# genkernel --no-clean --lvm all # echo dm-mod >> /etc/modules.autoload.d/kernel-2.6 # echo raid5 >> /etc/modules.autoload.d/kernel-2.6 # blockdev --report /dev/sd* RO RA SSZ BSZ StartSec Size Device rw 256 512 4096 0 1000204886016 /dev/sda rw 256 512 1024 63 1000202241024 /dev/sda1 rw 256 512 4096 0 1000204886016 /dev/sdb rw 256 512 1024 63 1000202241024 /dev/sdb1 rw 256 512 4096 0 1000204886016 /dev/sdc rw 256 512 1024 63 1000202241024 /dev/sdc1 rw 256 512 4096 0 1000204886016 /dev/sdd rw 256 512 1024 63 1000202241024 /dev/sdd1 rw 256 512 4096 0 1000204886016 /dev/sde rw 256 512 1024 63 1000202241024 /dev/sde1 rw 256 512 4096 0 1000204886016 /dev/sdf rw 256 512 1024 63 1000202241024 /dev/sdf1 # cfdisk /dev/sda # cfdisk /dev/sdb # cfdisk /dev/sdc # cfdisk /dev/sdd # cfdisk /dev/sde # cfdisk /dev/sdf # cd /dev/ # mkdir /dev/md # for i in `seq 0 11`; do mknod /dev/md/$i b 9 $i; ln -s md/$i md$i; done # # mdadm --create /dev/md0 --level=5 --bitmap=internal --raid-devices=6 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1
## This command will show you the health of your entire RAID
# watch cat /proc/mdstat Every 2.0s: cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md0 : active raid5 sdf1[6] sde1[4] sdd1[3] sdc1[2] sdb1[1] sda1[0] 4883799680 blocks level 5, 64k chunk, algorithm 2 [6/5] [UUUUU_] [>....................] recovery = 0.8% (8015744/976759936) finish=287.3min speed=56179K/sec bitmap: 0/233 pages [0KB], 2048KB chunk unused devices: <none>
## This command will give you detailed info on a specific RAID
# mdadm --detail /dev/md0 /dev/md0: Version : 0.90 Creation Time : Mon Jul 20 02:09:49 2009 Raid Level : raid5 Array Size : 4883799680 (4657.55 GiB 5001.01 GB) Used Dev Size : 976759936 (931.51 GiB 1000.20 GB) Raid Devices : 6 Total Devices : 6 Preferred Minor : 0 Persistence : Superblock is persistent Intent Bitmap : Internal Update Time : Mon Jul 20 02:11:50 2009 State : active, degraded, recovering Active Devices : 5 Working Devices : 6 Failed Devices : 0 Spare Devices : 1 Layout : left-symmetric Chunk Size : 64K Rebuild Status : 0% complete UUID : 653762f3:3e562b56:1499062a:2e44beb5 Events : 0.6 Number Major Minor RaidDevice State 0 8 1 0 active sync /dev/sda1 1 8 17 1 active sync /dev/sdb1 2 8 33 2 active sync /dev/sdc1 3 8 49 3 active sync /dev/sdd1 4 8 65 4 active sync /dev/sde1 6 8 81 5 spare rebuilding /dev/sdf1 # mdadm --detail --scan >> /etc/mdadm.conf -------- LVM --------
## Scan for existing volume groups (will result in nothing found)
# vgscan
## Activate Volume Groups (VG)
# vgchange -a y # pvcreate /dev/md0 # vgcreate vg00 /dev/md0 # lvcreate -l 1192333 -n vg vg00 # mke2fs -j /dev/vg00/vg df -H Filesystem Size Used Avail Use% Mounted on /dev/hda1 65G 39G 23G 64% / udev 11M 205k 11M 2% /dev shm 1.6G 0 1.6G 0% /dev/shm /dev/mapper/vg00-vg 5.0T 201M 4.7T 1% /raid
## That’s it!
## to add a failed drive back in, use:
# mdadm --manage /dev/md0 -a /dev/sdc1