Linux 软RAID命令

[[email protected] ~]# mdadm --create --verbose /dev/md0  --level=raid5 --raid-devices=3 /dev/sdb /dev/sdc /dev/sdd --spare-devices=1 /dev/sde

##########创建RAID

[[email protected] ~]# mdadm -Cv /dev/md0 -l5 -n3 /dev/sdb /dev/sdc /dev/sdd -x1 /dev/sde

##########创建RAID

[[email protected] ~]# cat /proc/mdstat

Personalities : [raid6] [raid5] [raid4] 

md0 : active raid5 sdd[2] sde[3](S) sdc[1] sdb[0]

      20971392 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]

unused devices: <none>

[[email protected] ~]# 

[[email protected] ~]# mkfs.ext3 /dev/md0

mke2fs 1.39 (29-May-2006)

Filesystem label=

OS type: Linux

Block size=4096 (log=2)

Fragment size=4096 (log=2)

2621440 inodes, 5242848 blocks

262142 blocks (5.00%) reserved for the super user

First data block=0

Maximum filesystem blocks=4294967296

160 block groups

32768 blocks per group, 32768 fragments per group

16384 inodes per group

Superblock backups stored on blocks: 

        32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 

        4096000

Writing inode tables: done                            

Creating journal (32768 blocks): done

Writing superblocks and filesystem accounting information: done

This filesystem will be automatically checked every 27 mounts or

180 days, whichever comes first.  Use tune2fs -c or -i to override.

[[email protected] ~]# mkdir /mnt/md0

[[email protected] ~]# mount /dev/md0 /mnt/md0

[[email protected] ~]# df -h

文件系统              容量  已用 可用 已用% 挂载点

/dev/mapper/VolGroup00-LogVol00

                       22G   20G  1.3G  94% /

/dev/sda1              99M   13M   82M  14% /boot

tmpfs                 3.0G     0  3.0G   0% /dev/shm

/dev/md0               20G  173M   19G   1% /mnt/md0

[[email protected] ~]# cd /mnt/md0

[[email protected] md0]# ls

lost+found

[[email protected] md0]# mdadm -D /dev/md0

/dev/md0:

        Version : 0.90

  Creation Time : Sat Oct 18 22:17:41 2014

     Raid Level : raid5

     Array Size : 20971392 (20.00 GiB 21.47 GB)

  Used Dev Size : 10485696 (10.00 GiB 10.74 GB)

   Raid Devices : 3

  Total Devices : 4

Preferred Minor : 0

    Persistence : Superblock is persistent

    Update Time : Sun Oct 19 13:25:42 2014

          State : clean

 Active Devices : 3

Working Devices : 4

 Failed Devices : 0

  Spare Devices : 1

         Layout : left-symmetric

     Chunk Size : 64K

           UUID : af76384d:8f52152b:7cd5b025:24d80ba5

         Events : 0.4

    Number   Major   Minor   RaidDevice State

       0       8       16        0      active sync   /dev/sdb

       1       8       32        1      active sync   /dev/sdc

       2       8       48        2      active sync   /dev/sdd

       3       8       64        -      spare   /dev/sde