两块磁盘创建RAID1镜像

两块磁盘创建RAID1镜像

添加两块磁盘并分区，将分区的系统类型改为fd

fdisk -l //sdb,sdc
fdisk /dev/sdb //
创建分区   n
提示选择分区类型  p
分区号  1
起始 默认
last 默认
t
fd
p
w

安装mdadm软件包并且检查磁盘

yum install mdadm.x86_64 -y
[root@apenglinux-002 ~]# mdadm -E /dev/sdb /dev/sdc
/dev/sdb:
   MBR Magic : aa55
Partition[0] :     20969472 sectors at         2048 (type fd)
/dev/sdc:
   MBR Magic : aa55
Partition[0] :     20969472 sectors at         2048 (type fd)

创建RAID1设备

[root@apenglinux-002 ~]# mdadm --create /dev/md0 --level=mirror --raid-devices=2 /dev/sdb1 /dev/sdc1
mdadm: Note: this array has metadata at the start 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=0.90
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.

[root@apenglinux-002 ~]# cat /proc/mdstat 
Personalities : [raid1] 
md0 : active raid1 sdc1[1] sdb1[0]
      10476544 blocks super 1.2 [2/2] [UU]
      [===============>.....]  resync = 78.2% (8202368/10476544) finish=0.1min speed=200018K/sec

unused devices: 

mdadm -E /dev/sd[b-c]1

mdadm --detail /dev/md0

在RAID设备上创建文件系统，并挂载，写入内容

mkfs.ext4 /dev/md0
mkdir /raid1
mount /dev/md0 /raid1
echo "raid test file" > /raid1/testraid.txt

开机自动挂载

echo "/dev/md0 /raid1 ext4 defaults 0 0" >> /etc/fstab

检查fstab中的条目是否有错误

mount -av

保存RAID的配置到文件“mdadm.conf”中

mdadm --detail --scan --verbose >> /etc/mdadm.conf

将磁盘sdc拔出重启，看看情况

mdadm --detail /dev/md0
...................以上省略......................
Number   Major   Minor   RaidDevice State
       0       8       17        0      active sync   /dev/sdb1
       -       0        0        1      removed

查看数据是否存在

cat /raid1/testraid.txt
raid test file