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MDADM
先在虚拟机上添加两块硬盘
查看一下操作系统
[root@web1 ~]# uname -a
Linux web1.abc.local 2.6.32-358.el6.x86_64#1 SMP Tue Jan 29 11:47:41 EST 2013 x86_64 x86_64 x86_64 GNU/Linux
[root@web1 ~]# cat /etc/redhat-release
Red Hat Enterprise Linux Server release 6.4(Santiago)
查看mdadm的版本信息
[root@web1 ~]# rpm -qi mdadm
Name : mdadm Relocations: (not relocatable)
Version : 3.2.5 Vendor: Red Hat, Inc.
Release : 4.el6 Build Date: Fri 07 Dec2012 12:14:45 AM CST
Install Date: Fri 01 Aug 2014 06:05:19 PMCST Build Host:x86-003.build.bos.redhat.com
Group : System Environment/Base Source RPM: mdadm-3.2.5-4.el6.src.rpm
Size : 860588 License: GPLv2+
Signature : RSA/8, Mon 28 Jan 2013 10:48:06 PM CST, Key ID 199e2f91fd431d51
Packager : Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>
URL : http://www.kernel.org/pub/linux/utils/raid/mdadm/
Summary : The mdadm program controls Linux md devices (software RAID arrays)
Description :
The mdadm program is used to create,manage, and monitor Linux MD (software
RAID)devices. As such, it provides similarfunctionality to the raidtools
package. However, mdadm is a single program, and it can perform
almost all functions without aconfiguration file, though a configuration
file can be used to help with some commontasks.
1.分区操作
[root@web1 ~]# fdisk /dev/sdb
WARNING:DOS-compatible mode is deprecated. It‘s strongly recommended to
switch off the mode (command ‘c‘) and change display units to
sectors (command ‘u‘).
Command (m forhelp): p
Disk /dev/sdb:32.2 GB, 32212254720 bytes
255 heads, 63 sectors/track, 3916 cylinders
Units = cylinders of 16065 * 512 = 8225280bytes
Sector size (logical/physical): 512 bytes /512 bytes
I/O size (minimum/optimal): 512 bytes / 512bytes
Disk identifier: 0x09a1a34a
Device Boot Start End Blocks Id System
Command (m forhelp): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-3916, default 1):
Using defaultvalue 1
Last cylinder, +cylinders or +size{K,M,G}(1-3916, default 3916):
Using default value 3916
Command (m forhelp): p
Disk /dev/sdb:32.2 GB, 32212254720 bytes
255 heads, 63 sectors/track, 3916 cylinders
Units = cylinders of 16065 * 512 = 8225280bytes
Sector size (logical/physical): 512 bytes /512 bytes
I/O size (minimum/optimal): 512 bytes / 512bytes
Disk identifier: 0x09a1a34a
Device Boot Start End Blocks Id System
/dev/sdb1 1 3916 31455238+ 83 Linux
Command (m forhelp): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
对dev/sdc进行同样的操作
通过fdisk -l查看
[root@web1 ~]# fdisk -l /dev/sdb
Disk /dev/sdb:32.2 GB, 32212254720 bytes
255 heads, 63 sectors/track, 3916 cylinders
Units = cylinders of 16065 * 512 = 8225280bytes
Sector size (logical/physical): 512 bytes /512 bytes
I/O size (minimum/optimal): 512 bytes / 512bytes
Disk identifier: 0x09a1a34a
Device Boot Start End Blocks Id System
/dev/sdb1 1 3916 31455238+ 83 Linux
[root@web1 ~]# fdisk -l /dev/sdc
Disk /dev/sdc:32.2 GB, 32212254720 bytes
255 heads, 63 sectors/track, 3916 cylinders
Units = cylinders of 16065 * 512 = 8225280bytes
Sector size (logical/physical): 512 bytes /512 bytes
I/O size (minimum/optimal): 512 bytes / 512bytes
Disk identifier: 0x6881f1ac
Device Boot Start End Blocks Id System
/dev/sdc1 1 3916 31455238+ 83 Linux
2.建立RAID1
[root@web1 ~]# mdadm -C /dev/md0 -l 1 -n 2/dev/sdb1 /dev/sdc1
mdadm: Note: this array has metadata at thestart and
may not be suitable as a boot device. If you plan to
store ‘/boot‘ on this device please ensure that
your boot-loader understands md/v1.x metadata, or use
--metadata=http://www.mamicode.com/0.90
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.
输入tail -f /var/log/messages打开日志，在日志中可看到如下内容
md: bind<sdb1>
md: bind<sdc1>
md: raid1 personality registered for level1
bio: create slab <bio-1> at 1
md/raid1:md0: not clean -- startingbackground reconstruction
md/raid1:md0: active with 2 out of 2mirrors
md0: detected capacity change from 0 to32193249280
md: resync of RAID array md0
md: minimum _guaranteed_ speed: 1000 KB/sec/disk.
md: using maximum available idle IObandwidth (but not more than 200000 KB/sec) for resync.
md: using 128k window, over a total of31438720k.
md0:unknown partition table
3.创建文件系统
先格式化该磁盘阵列
[root@web1 ~]# mkfs.ext4 /dev/md0
mke2fs 1.41.12 (17-May-2010)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
1966080 inodes, 7859680 blocks
392984 blocks (5.00%) reserved for thesuper user
First data block=0
Maximum filesystem blocks=4294967296
240 block groups
32768 blocks per group, 32768 fragments pergroup
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000
Writing inodetables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystemaccounting information: done
This filesystemwill be automatically checked every 30 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
挂载
[root@web1 ~]# mount /dev/md0 /data
[root@web1 ~]# ll /data
total 16
drwx------2 root root 16384 Aug 13 19:18 lost+found
[root@web1 ~]# vi /etc/fstab
#
# /etc/fstab
# Created by anaconda on Fri Aug 1 18:02:23 2014
#
# Accessible filesystems, by reference, aremaintained under ‘/dev/disk‘
# See man pagesfstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/VolGroup-lv_root / ext4 defaults 1 1
UUID=e3738a2c-63a9-4c8d-99db-8e0794534f45/boot ext4 defaults 1 2
/dev/mapper/VolGroup-lv_swap swap swap defaults 0 0
tmpfs /dev/shm tmpfs defaults 0 0
devpts /dev/pts devpts gid=5,mode=620 0 0
sysfs /sys sysfs defaults 0 0
proc /proc proc defaults 0 0
/dev/md0 /data ext4 defaults 0 0
[root@web1 ~]# mdadm -Ds
ARRAY /dev/md0 metadata=http://www.mamicode.com/1.2name=web1.abc.local:0 UUID=562b4e91:606904d1:33e5d565:e5a9f609
写入到配置文件
[root@web1 ~]# mdadm -Ds >>/etc/mdadm.conf
重新启动验证
[root@web1 ~]# reboot
[root@web1 ~]# mount
/dev/mapper/VolGroup-lv_root on / type ext4(rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
tmpfs on /dev/shm type tmpfs (rw)
/dev/sda1 on /boot type ext4 (rw)
/dev/md0 on /data type ext4 (rw)
none on /proc/sys/fs/binfmt_misc typebinfmt_misc (rw)
[root@web1 ~]# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb1[0] sdc1[1]
31438720 blocks super 1.2 [2/2] [UU]
unused devices: <none>
4.模拟故障
删除一块硬盘
# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb1[0](F) sdc1[1]
31438720 blocks super 1.2 [2/1] [_U]
unused devices: <none>
5.RAID1重建
新添加一块名为30GBC的磁盘
在线加入新组成单元
[root@web1 ~]# mdadm /dev/md0 -a /dev/sdb1
[root@web1 ~]# cat /proc/mdstat
本文出自 “thawliu” 博客，请务必保留此出处http://thawliu.blog.51cto.com/9274422/1540297