Linux 軟體磁碟陣列
基本查詢命令語法
- cat /proc/mdstat |h
Personalities : [raid1] read_ahead 1024 sectors md3 : active raid1 hdc5[0] hdd5[1] 115113600 blocks [2/2] [UU] md2 : active raid1 hdc3[0] hdd3[1] 20482752 blocks [2/2] [UU] md1 : active raid1 hdc2[0] hdd2[1] 20482752 blocks [2/2] [UU] md0 : active raid1 hdc1[0] hdd1[1] 208704 blocks [2/2] [UU] unused devices: <none>
- lsraid |h
lsraid -a /dev/md0 [root@mail etc]# lsraid -a /dev/md0 [dev 9, 0] /dev/md0 57F98AC6.91021808.E5F058A3.91E9FE17 online [dev 22, 1] /dev/hdc1 57F98AC6.91021808.E5F058A3.91E9FE17 good [dev 22, 65] /dev/hdd1 57F98AC6.91021808.E5F058A3.91E9FE17 good [root@mail etc]# lsraid -a /dev/md1 [dev 9, 1] /dev/md1 4A2262E4.6B0C39AA.59C5AEAF.4FC41204 online [dev 22, 2] /dev/hdc2 4A2262E4.6B0C39AA.59C5AEAF.4FC41204 good [dev 22, 66] /dev/hdd2 4A2262E4.6B0C39AA.59C5AEAF.4FC41204 good [root@mail etc]# lsraid -a /dev/md2 [dev 9, 2] /dev/md2 4A103E27.D5B51E66.AA3D7DEA.EF7AB400 online [dev 22, 3] /dev/hdc3 4A103E27.D5B51E66.AA3D7DEA.EF7AB400 good [dev 22, 67] /dev/hdd3 4A103E27.D5B51E66.AA3D7DEA.EF7AB400 good
- mdadm |h
mdadm --detail /dev/md0 /dev/md0: Version : 00.90.00 Creation Time : Tue Aug 31 23:35:15 2004 Raid Level : raid1 Array Size : 208704 (203.81 MiB 213.71 MB) Device Size : 208704 (203.81 MiB 213.71 MB) Raid Devices : 2 Total Devices : 2 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Tue Oct 24 21:28:00 2006 State : dirty, no-errors Active Devices : 2 Working Devices : 2 Failed Devices : 0 Spare Devices : 0 Number Major Minor RaidDevice State 0 22 1 0 active sync /dev/hdc1 1 22 65 1 active sync /dev/hdd1 UUID : 463dfe4b:903e3a5e:be876c16:653cc561
建立軟體磁碟陣列方法
- 透過安裝 CentOS 過程中選擇建立 SoftRAID
使用命令列詳細過程
- 將 hda1 與 hdc1 建立為 raid1 的 md0 語法
# mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/hda1 /dev/hdc1
- 查看 md0 建立的狀況
# cat /proc/mdstat Personalities : [raid1] read_ahead 1024 sectors md0 : active raid1 hda1[0] hdc1[1] 56261376 blocks [2/2] [UU]
出現 RAID 異常切換方法
- md0 發生異常時的狀況:
# cat /proc/mdstat
Personalities : [raid1]
md1 : active raid1 sdb2[1] sda2[0]
4297280 blocks [2/2] [UU]
md0 : active raid1 sdb1[1]
235520832 blocks [2/1] [_U]
- 將 md0 內出問題的 sda1 移除
# mdadm /dev/md0 --remove /dev/sda1 mdadm: hot removed /dev/sda1
- 當 sda 更換好之後，再將 sda1 加回 md0 內
# mdadm /dev/md0 --add /dev/sda1 mdadm: hot added /dev/sda1
- 這時會看到加回 md0 的狀況
# cat /proc/mdstat
Personalities : [raid1]
md1 : active raid1 sdb2[1] sda2[0]
4297280 blocks [2/2] [UU]
md0 : active raid1 sda1[2] sdb1[1]
235520832 blocks [2/1] [_U]
[=>...................] recovery = 6.4% (15183872/235520832)
finish=79.6min speed=46101K/sec
unused devices: