Linux下创建软RAID1实战

[root@RHEL7 ~]# date

Thu Aug 18 20:45:34 CST 2016
[root@RHEL7 ~]# fdisk /dev/sdc
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xe1f55a32.
Command (m for help): p
Disk /dev/sdc: 5368 MB, 5368709120 bytes, 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xe1f55a32
Device Boot Start End Blocks Id System
Command (m for help): n
Partition type:
p primary (0 primary, 0 extended, 4 free)
e extended
Select (default p): p
Partition number (1-4, default 1):
First sector (2048-10485759, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-10485759, default 10485759):
Using default value 10485759
Partition 1 of type Linux and of size 5 GiB is set
Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): fd #fd：linux raid mode
Changed type of partition 'Linux' to 'Linux raid autodetect'
Command (m for help): p
Disk /dev/sdc: 5368 MB, 5368709120 bytes, 10485760 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xe1f55a32
Device Boot Start End Blocks Id System
/dev/sdc1 2048 10485759 5241856 fd Linux raid autodetect
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@RHEL7 ~]# partprobe /dev/sdb
[root@RHEL7 ~]# partprobe /dev/sdc
[root@RHEL7 ~]# ls /dev/sdb*
/dev/sdb /dev/sdb1
[root@RHEL7 ~]# ls /dev/sdc*
/dev/sdc /dev/sdc1
检查磁盘是 否可以创建RAID1
[root@RHEL7 ~]# mdadm -E /dev/sd[b-c]
/dev/sdb:
MBR Magic : aa55
Partition[0] : 10483712 sectors at 2048 (type fd)
/dev/sdc:
MBR Magic : aa55
Partition[0] : 10483712 sectors at 2048 (type fd)
创建RAID1
[root@RHEL7 ~]# mdadm -C -v /dev/md1 -l 1 -n 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
mdadm: size set to 5237696K
Continue creating array? y
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md1 started.
查看RAID状态
[root@RHEL7 ~]# cat /proc/mdstat
Personalities : [raid1]
md1 : active raid1 sdc1[1] sdb1[0]
5237696 blocks super 1.2 [2/2] [UU]
[============>........] resync = 60.6% (3175232/5237696) finish=0.1min speed=211682K/sec
unused devices: <none>
[root@RHEL7 ~]# watch cat /proc/mdstat
查看两块盘的状态
[root@RHEL7 ~]# mdadm -E /dev/sdb1 /dev/sdc1
/dev/sdb1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : b3f8134a:abc56378:c6498702:55215f10
Name : RHEL7.2:1 (local to host RHEL7.2)
Creation Time : Thu Aug 18 20:49:27 2016
Raid Level : raid1
Raid Devices : 2
Avail Dev Size : 10475520 (5.00 GiB 5.36 GB)
Array Size : 5237696 (5.00 GiB 5.36 GB)
Used Dev Size : 10475392 (5.00 GiB 5.36 GB)
Data Offset : 8192 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 4cb9ba13:784b2294:29e78967:d93d8a94
Update Time : Thu Aug 18 20:49:54 2016
Checksum : 595f46a0 - correct
Events : 17
Device Role : Active device 0
Array State : AA ('A' == active, '.' == missing)
/dev/sdc1:
Magic : a92b4efc
Version : 1.2
Feature Map : 0x0
Array UUID : b3f8134a:abc56378:c6498702:55215f10
Name : RHEL7.2:1 (local to host RHEL7.2)
Creation Time : Thu Aug 18 20:49:27 2016
Raid Level : raid1
Raid Devices : 2
Avail Dev Size : 10475520 (5.00 GiB 5.36 GB)
Array Size : 5237696 (5.00 GiB 5.36 GB)
Used Dev Size : 10475392 (5.00 GiB 5.36 GB)
Data Offset : 8192 sectors
Super Offset : 8 sectors
State : clean
Device UUID : 841e8e8c:b3ffe403:a487475c:c899e735
Update Time : Thu Aug 18 20:49:54 2016
Checksum : d8105c7d - correct
Events : 17
Device Role : Active device 1
Array State : AA ('A' == active, '.' == missing)

查看RAID1状态
[root@RHEL7 ~]# mdadm -D /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Thu Aug 18 20:49:27 2016
Raid Level : raid1
Array Size : 5237696 (5.00 GiB 5.36 GB)
Used Dev Size : 5237696 (5.00 GiB 5.36 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent
Update Time : Thu Aug 18 20:49:54 2016
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0
Name : RHEL7.2:1 (local to host RHEL7.2)
UUID : b3f8134a:abc56378:c6498702:55215f10
Events : 17
Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
[root@RHEL7 ~]#
格式化
[root@RHEL7 ~]# mkfs.xfs -f /dev/md1
meta-data=/dev/md1 isize=256 agcount=4, agsize=327356 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0
data = bsize=4096 blocks=1309424, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal log bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
[root@RHEL7 ~]# mkdir /raid1
[root@RHEL7 ~]# mount /dev/md1 /raid1/
[root@RHEL7 ~]# cd /raid1/
[root@RHEL7 raid1]# dd if=/dev/zero of=/raid1/aa bs=2M count=100
100+0 records in
100+0 records out
209715200 bytes (210 MB) copied, 1.7897 s, 117 MB/s
[root@RHEL7 raid1]# ls
aa
[root@RHEL7 raid1]# du /raid1
204800 /raid1