RAID可以大幅度的提高磁盘性能,以及可靠性,这么好的技术怎么能不掌握呢!此篇介绍一些常见RAID,及其在Linux上的软RAID创建方法。


mdadm

  • 创建软RAID
mdadm -C -v /dev/创建的设备名 -l级别 -n数量 添加的磁盘 [-x数量 添加的热备份盘]

-C:创建一个新的阵列--create

-v:显示细节--verbose

-l:设定RAID级别--level=

-n:指定阵列中可用device数目--raid-devices=

-x:指定初始阵列的富余device数目--spare-devices=,空闲盘(热备磁盘)能在工作盘损坏后自动顶替

  • 查看详细信息
mdadm -D /dev/设备名

-D:打印一个或多个md device的详细信息--detail

  • 查看RAID的状态
cat /proc/mdstat
  • 模拟损坏
mdadm -f /dev/设备名 磁盘

-f:模拟损坏fail

  • 移除损坏
mdadm -r /dev/设备名 磁盘

-r:移除remove

  • 添加新硬盘作为热备份盘
mdadm -a /dev/设备名 磁盘

-a:添加add


RAID0

RAID0俗称条带,它将两个或多个硬盘组成一个逻辑硬盘,容量是所有硬盘之和,因为是多个硬盘组合成一个,故可并行写操作,写入速度提高,但此方式硬盘数据没有冗余,没有容错,一旦一个物理硬盘损坏,则所有数据均丢失。因而,RAID0适合于对数据量大,但安全性要求不高的场景,比如音像、视频文件的存储等。

实验RAID0创建,格式化,挂载使用。

1.添加220G的硬盘,分区,类型IDfd

[root@localhost ~]# fdisk -l | grep raid
/dev/sdb1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdc1 2048 41943039 20970496 fd Linux raid autodetect

2.创建RAID0

[root@localhost ~]# mdadm -C -v /dev/md0 -l0 -n2 /dev/sd{b,c}1
mdadm: chunk size defaults to 512K
mdadm: Fail create md0 when using /sys/module/md_mod/parameters/new_array
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md0 started.

3.查看raidstat状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid0]
md0 : active raid0 sdc1[1] sdb1[0]
41906176 blocks super 1.2 512k chunks unused devices: <none>

4.查看RAID0的详细信息。

[root@localhost ~]# mdadm -D /dev/md0
/dev/md0:
Version : 1.2
Creation Time : Sun Aug 25 15:28:13 2019
Raid Level : raid0
Array Size : 41906176 (39.96 GiB 42.91 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 15:28:13 2019
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Chunk Size : 512K Consistency Policy : none Name : localhost:0 (local to host localhost)
UUID : 7ff54c57:b99a59da:6b56c6d5:a4576ccf
Events : 0 Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1

5.格式化。

[root@localhost ~]# mkfs.xfs /dev/md0
meta-data=/dev/md0 isize=512 agcount=16, agsize=654720 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=10475520, imaxpct=25
= sunit=128 swidth=256 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=5120, version=2
= sectsz=512 sunit=8 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0

6.挂载使用。

[root@localhost ~]# mkdir /mnt/md0
[root@localhost ~]# mount /dev/md0 /mnt/md0/
[root@localhost ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/centos-root xfs 17G 1013M 16G 6% /
devtmpfs devtmpfs 901M 0 901M 0% /dev
tmpfs tmpfs 912M 0 912M 0% /dev/shm
tmpfs tmpfs 912M 8.7M 904M 1% /run
tmpfs tmpfs 912M 0 912M 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 143M 872M 15% /boot
tmpfs tmpfs 183M 0 183M 0% /run/user/0
/dev/md0 xfs 40G 33M 40G 1% /mnt/md0

RAID1

RAID1俗称镜像,它最少由两个硬盘组成,且两个硬盘上存储的数据均相同,以实现数据冗余。RAID1读操作速度有所提高,写操作理论上与单硬盘速度一样,但由于数据需要同时写入所有硬盘,实际上稍为下降。容错性是所有组合方式里最好的,只要有一块硬盘正常,则能保持正常工作。但它对硬盘容量的利用率则是最低,只有50%,因而成本也是最高。RAID1适合对数据安全性要求非常高的场景,比如存储数据库数据文件之类。

实验RAID1创建,格式化,挂载使用,故障模拟,重新添加热备份。

1.添加320G的硬盘,分区,类型IDfd

[root@localhost ~]# fdisk -l | grep raid
/dev/sdb1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdc1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdd1 2048 41943039 20970496 fd Linux raid autodetect

2.创建RAID1,并添加1个热备份盘。

[root@localhost ~]# mdadm -C -v /dev/md1 -l1 -n2 /dev/sd{b,c}1 -x1 /dev/sdd1
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 20953088K
Continue creating array? y
mdadm: Fail create md1 when using /sys/module/md_mod/parameters/new_array
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md1 started.

3.查看raidstat状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md1 : active raid1 sdd1[2](S) sdc1[1] sdb1[0]
20953088 blocks super 1.2 [2/2] [UU]
[========>............] resync = 44.6% (9345792/20953088) finish=0.9min speed=203996K/sec unused devices: <none>
[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md1 : active raid1 sdd1[2](S) sdc1[1] sdb1[0]
20953088 blocks super 1.2 [2/2] [UU] unused devices: <none>

4.查看RAID1的详细信息。

[root@localhost ~]# mdadm -D /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Sun Aug 25 15:38:44 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 3
Persistence : Superblock is persistent Update Time : Sun Aug 25 15:39:24 2019
State : clean, resyncing
Active Devices : 2
Working Devices : 3
Failed Devices : 0
Spare Devices : 1 Consistency Policy : resync Resync Status : 40% complete Name : localhost:1 (local to host localhost)
UUID : b921e8b3:a18e2fc9:11706ba4:ed633dfd
Events : 6 Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1 2 8 49 - spare /dev/sdd1

5.格式化。

[root@localhost ~]# mkfs.xfs /dev/md1
meta-data=/dev/md1 isize=512 agcount=4, agsize=1309568 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=5238272, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
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

6.挂载使用。

[root@localhost ~]# mkdir /mnt/md1
[root@localhost ~]# mount /dev/md1 /mnt/md1/
[root@localhost ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/centos-root xfs 17G 1014M 16G 6% /
devtmpfs devtmpfs 901M 0 901M 0% /dev
tmpfs tmpfs 912M 0 912M 0% /dev/shm
tmpfs tmpfs 912M 8.7M 904M 1% /run
tmpfs tmpfs 912M 0 912M 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 143M 872M 15% /boot
tmpfs tmpfs 183M 0 183M 0% /run/user/0
/dev/md1 xfs 20G 33M 20G 1% /mnt/md1

7.创建测试文件。

[root@localhost ~]# touch /mnt/md1/test{1..9}.txt
[root@localhost ~]# ls /mnt/md1/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

8.故障模拟。

[root@localhost ~]# mdadm -f /dev/md1 /dev/sdb1
mdadm: set /dev/sdb1 faulty in /dev/md1

9.查看测试文件。

[root@localhost ~]# ls /mnt/md1/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

10.查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md1 : active raid1 sdd1[2] sdc1[1] sdb1[0](F)
20953088 blocks super 1.2 [2/1] [_U]
[=====>...............] recovery = 26.7% (5600384/20953088) finish=1.2min speed=200013K/sec unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Sun Aug 25 15:38:44 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 3
Persistence : Superblock is persistent Update Time : Sun Aug 25 15:47:57 2019
State : active, degraded, recovering
Active Devices : 1
Working Devices : 2
Failed Devices : 1
Spare Devices : 1 Consistency Policy : resync Rebuild Status : 17% complete Name : localhost:1 (local to host localhost)
UUID : b921e8b3:a18e2fc9:11706ba4:ed633dfd
Events : 22 Number Major Minor RaidDevice State
2 8 49 0 spare rebuilding /dev/sdd1
1 8 33 1 active sync /dev/sdc1 0 8 17 - faulty /dev/sdb1

11.再次查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md1 : active raid1 sdd1[2] sdc1[1] sdb1[0](F)
20953088 blocks super 1.2 [2/2] [UU] unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Sun Aug 25 15:38:44 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 3
Persistence : Superblock is persistent Update Time : Sun Aug 25 15:49:28 2019
State : active
Active Devices : 2
Working Devices : 2
Failed Devices : 1
Spare Devices : 0 Consistency Policy : resync Name : localhost:1 (local to host localhost)
UUID : b921e8b3:a18e2fc9:11706ba4:ed633dfd
Events : 37 Number Major Minor RaidDevice State
2 8 49 0 active sync /dev/sdd1
1 8 33 1 active sync /dev/sdc1 0 8 17 - faulty /dev/sdb1

12.移除损坏的磁盘

[root@localhost ~]# mdadm -r /dev/md1 /dev/sdb1
mdadm: hot removed /dev/sdb1 from /dev/md1
[root@localhost ~]# mdadm -D /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Sun Aug 25 15:38:44 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 15:52:57 2019
State : active
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Consistency Policy : resync Name : localhost:1 (local to host localhost)
UUID : b921e8b3:a18e2fc9:11706ba4:ed633dfd
Events : 38 Number Major Minor RaidDevice State
2 8 49 0 active sync /dev/sdd1
1 8 33 1 active sync /dev/sdc1

13.重新添加热备份盘。

[root@localhost ~]# mdadm -a /dev/md1 /dev/sdb1
mdadm: added /dev/sdb1
[root@localhost ~]# mdadm -D /dev/md1
/dev/md1:
Version : 1.2
Creation Time : Sun Aug 25 15:38:44 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 3
Persistence : Superblock is persistent Update Time : Sun Aug 25 15:53:32 2019
State : active
Active Devices : 2
Working Devices : 3
Failed Devices : 0
Spare Devices : 1 Consistency Policy : resync Name : localhost:1 (local to host localhost)
UUID : b921e8b3:a18e2fc9:11706ba4:ed633dfd
Events : 39 Number Major Minor RaidDevice State
2 8 49 0 active sync /dev/sdd1
1 8 33 1 active sync /dev/sdc1 3 8 17 - spare /dev/sdb1

RAID5

RAID5最少由三个硬盘组成,它将数据分散存储于阵列中的每个硬盘,并且还伴有一个数据校验位,数据位与校验位通过算法能相互验证,当丢失其中的一位时,RAID控制器能通过算法,利用其它两位数据将丢失的数据进行计算还原。因而RAID5最多能允许一个硬盘损坏,有容错性。RAID5相对于其它的组合方式,在容错与成本方面有一个平衡,因而受到大多数使用者的欢迎。一般的磁盘阵列,最常使用的就是RAID5这种方式。

实验RAID5创建,格式化,挂载使用,故障模拟,重新添加热备份。

1.添加420G的硬盘,分区,类型IDfd

[root@localhost ~]# fdisk -l | grep raid
/dev/sdb1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdc1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdd1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sde1 2048 41943039 20970496 fd Linux raid autodetect

2.创建RAID5,并添加1个热备份盘。

[root@localhost ~]# mdadm -C -v /dev/md5 -l5 -n3 /dev/sd[b-d]1 -x1 /dev/sde1
mdadm: layout defaults to left-symmetric
mdadm: layout defaults to left-symmetric
mdadm: chunk size defaults to 512K
mdadm: size set to 20953088K
mdadm: Fail create md5 when using /sys/module/md_mod/parameters/new_array
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md5 started.

3.查看raidstat状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md5 : active raid5 sdd1[4] sde1[3](S) sdc1[1] sdb1[0]
41906176 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/2] [UU_]
[====>................] recovery = 24.1% (5057340/20953088) finish=1.3min speed=202293K/sec unused devices: <none>
[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md5 : active raid5 sdd1[4] sde1[3](S) sdc1[1] sdb1[0]
41906176 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU] unused devices: <none>

4.查看RAID5的详细信息。

[root@localhost ~]# mdadm -D /dev/md5
/dev/md5:
Version : 1.2
Creation Time : Sun Aug 25 16:13:44 2019
Raid Level : raid5
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 3
Total Devices : 4
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:15:29 2019
State : clean
Active Devices : 3
Working Devices : 4
Failed Devices : 0
Spare Devices : 1 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Name : localhost:5 (local to host localhost)
UUID : a055094e:9adaff79:2edae9b9:0dcc3f1b
Events : 18 Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
4 8 49 2 active sync /dev/sdd1 3 8 65 - spare /dev/sde1

5.格式化。

[root@localhost ~]# mkfs.xfs /dev/md5
meta-data=/dev/md5 isize=512 agcount=16, agsize=654720 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=10475520, imaxpct=25
= sunit=128 swidth=256 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=5120, version=2
= sectsz=512 sunit=8 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0

6.挂载使用。

[root@localhost ~]# mkdir /mnt/md5
[root@localhost ~]# mount /dev/md5 /mnt/md5/
[root@localhost ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/centos-root xfs 17G 1014M 16G 6% /
devtmpfs devtmpfs 901M 0 901M 0% /dev
tmpfs tmpfs 912M 0 912M 0% /dev/shm
tmpfs tmpfs 912M 8.7M 904M 1% /run
tmpfs tmpfs 912M 0 912M 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 143M 872M 15% /boot
tmpfs tmpfs 183M 0 183M 0% /run/user/0
/dev/md5 xfs 40G 33M 40G 1% /mnt/md5

7.创建测试文件。

[root@localhost ~]# touch /mnt/md5/test{1..9}.txt
[root@localhost ~]# ls /mnt/md5/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

8.故障模拟。

[root@localhost ~]# mdadm -f /dev/md5 /dev/sdb1
mdadm: set /dev/sdb1 faulty in /dev/md5

9.查看测试文件。

[root@localhost ~]# ls /mnt/md5/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

10.查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md5 : active raid5 sdd1[4] sde1[3] sdc1[1] sdb1[0](F)
41906176 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/2] [_UU]
[====>................] recovery = 21.0% (4411136/20953088) finish=1.3min speed=210054K/sec unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md5
/dev/md5:
Version : 1.2
Creation Time : Sun Aug 25 16:13:44 2019
Raid Level : raid5
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 3
Total Devices : 4
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:21:31 2019
State : clean, degraded, recovering
Active Devices : 2
Working Devices : 3
Failed Devices : 1
Spare Devices : 1 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Rebuild Status : 12% complete Name : localhost:5 (local to host localhost)
UUID : a055094e:9adaff79:2edae9b9:0dcc3f1b
Events : 23 Number Major Minor RaidDevice State
3 8 65 0 spare rebuilding /dev/sde1
1 8 33 1 active sync /dev/sdc1
4 8 49 2 active sync /dev/sdd1 0 8 17 - faulty /dev/sdb1

11.再次查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md5 : active raid5 sdd1[4] sde1[3] sdc1[1] sdb1[0](F)
41906176 blocks super 1.2 level 5, 512k chunk, algorithm 2 [3/3] [UUU] unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md5
/dev/md5:
Version : 1.2
Creation Time : Sun Aug 25 16:13:44 2019
Raid Level : raid5
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 3
Total Devices : 4
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:23:09 2019
State : clean
Active Devices : 3
Working Devices : 3
Failed Devices : 1
Spare Devices : 0 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Name : localhost:5 (local to host localhost)
UUID : a055094e:9adaff79:2edae9b9:0dcc3f1b
Events : 39 Number Major Minor RaidDevice State
3 8 65 0 active sync /dev/sde1
1 8 33 1 active sync /dev/sdc1
4 8 49 2 active sync /dev/sdd1 0 8 17 - faulty /dev/sdb1

12.移除损坏的磁盘。

[root@localhost ~]# mdadm -r /dev/md5 /dev/sdb1
mdadm: hot removed /dev/sdb1 from /dev/md5
[root@localhost ~]# mdadm -D /dev/md5
/dev/md5:
Version : 1.2
Creation Time : Sun Aug 25 16:13:44 2019
Raid Level : raid5
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 3
Total Devices : 3
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:25:01 2019
State : clean
Active Devices : 3
Working Devices : 3
Failed Devices : 0
Spare Devices : 0 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Name : localhost:5 (local to host localhost)
UUID : a055094e:9adaff79:2edae9b9:0dcc3f1b
Events : 40 Number Major Minor RaidDevice State
3 8 65 0 active sync /dev/sde1
1 8 33 1 active sync /dev/sdc1
4 8 49 2 active sync /dev/sdd1

13.重新添加热备份盘。

[root@localhost ~]# mdadm -a /dev/md5 /dev/sdb1
mdadm: added /dev/sdb1
[root@localhost ~]# mdadm -D /dev/md5
/dev/md5:
Version : 1.2
Creation Time : Sun Aug 25 16:13:44 2019
Raid Level : raid5
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 3
Total Devices : 4
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:25:22 2019
State : clean
Active Devices : 3
Working Devices : 4
Failed Devices : 0
Spare Devices : 1 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Name : localhost:5 (local to host localhost)
UUID : a055094e:9adaff79:2edae9b9:0dcc3f1b
Events : 41 Number Major Minor RaidDevice State
3 8 65 0 active sync /dev/sde1
1 8 33 1 active sync /dev/sdc1
4 8 49 2 active sync /dev/sdd1 5 8 17 - spare /dev/sdb1

RAID6

RAID6是在RAID5的基础上改良而成的,RAID6再将数据校验位增加一位,所以允许损坏的硬盘数量也由 RAID5的一个增加到二个。由于同一阵列中两个硬盘同时损坏的概率非常少,所以,RAID6用增加一块硬盘的代价,换来了比RAID5更高的数据安全性。

实验RAID6创建,格式化,挂载使用,故障模拟,重新添加热备份。

1.添加620G的硬盘,分区,类型IDfd

[root@localhost ~]# fdisk -l | grep raid
/dev/sdb1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdc1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdd1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sde1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdf1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdg1 2048 41943039 20970496 fd Linux raid autodetect

2.创建RAID6,并添加2个热备份盘。

[root@localhost ~]# mdadm -C -v /dev/md6 -l6 -n4 /dev/sd[b-e]1 -x2 /dev/sd[f-g]1
mdadm: layout defaults to left-symmetric
mdadm: layout defaults to left-symmetric
mdadm: chunk size defaults to 512K
mdadm: size set to 20953088K
mdadm: Fail create md6 when using /sys/module/md_mod/parameters/new_array
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md6 started.

3.查看raidstat状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md6 : active raid6 sdg1[5](S) sdf1[4](S) sde1[3] sdd1[2] sdc1[1] sdb1[0]
41906176 blocks super 1.2 level 6, 512k chunk, algorithm 2 [4/4] [UUUU]
[===>.................] resync = 18.9% (3962940/20953088) finish=1.3min speed=208575K/sec unused devices: <none>
[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md6 : active raid6 sdg1[5](S) sdf1[4](S) sde1[3] sdd1[2] sdc1[1] sdb1[0]
41906176 blocks super 1.2 level 6, 512k chunk, algorithm 2 [4/4] [UUUU] unused devices: <none>

4.查看RAID6的详细信息。

[root@localhost ~]# mdadm -D /dev/md6
/dev/md6:
Version : 1.2
Creation Time : Sun Aug 25 16:34:36 2019
Raid Level : raid6
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 4
Total Devices : 6
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:34:43 2019
State : clean, resyncing
Active Devices : 4
Working Devices : 6
Failed Devices : 0
Spare Devices : 2 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Resync Status : 10% complete Name : localhost:6 (local to host localhost)
UUID : 7c3d15a2:4066f2c6:742f3e4c:82aae1bb
Events : 1 Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
2 8 49 2 active sync /dev/sdd1
3 8 65 3 active sync /dev/sde1 4 8 81 - spare /dev/sdf1
5 8 97 - spare /dev/sdg1

5.格式化。

[root@localhost ~]# mkfs.xfs /dev/md6
meta-data=/dev/md6 isize=512 agcount=16, agsize=654720 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=10475520, imaxpct=25
= sunit=128 swidth=256 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=5120, version=2
= sectsz=512 sunit=8 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0

6.挂载使用。

[root@localhost ~]# mkdir /mnt/md6
[root@localhost ~]# mount /dev/md6 /mnt/md6/
[root@localhost ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/centos-root xfs 17G 1014M 16G 6% /
devtmpfs devtmpfs 901M 0 901M 0% /dev
tmpfs tmpfs 912M 0 912M 0% /dev/shm
tmpfs tmpfs 912M 8.7M 903M 1% /run
tmpfs tmpfs 912M 0 912M 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 143M 872M 15% /boot
tmpfs tmpfs 183M 0 183M 0% /run/user/0
/dev/md6 xfs 40G 33M 40G 1% /mnt/md6

7.创建测试文件。

[root@localhost ~]# touch /mnt/md6/test{1..9}.txt
[root@localhost ~]# ls /mnt/md6/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

8.故障模拟。

[root@localhost ~]# mdadm -f /dev/md6 /dev/sdb1
mdadm: set /dev/sdb1 faulty in /dev/md6
[root@localhost ~]# mdadm -f /dev/md6 /dev/sdc1
mdadm: set /dev/sdc1 faulty in /dev/md6

9.查看测试文件。

[root@localhost ~]# ls /mnt/md6/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

10.查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md6 : active raid6 sdg1[5] sdf1[4] sde1[3] sdd1[2] sdc1[1](F) sdb1[0](F)
41906176 blocks super 1.2 level 6, 512k chunk, algorithm 2 [4/2] [__UU]
[====>................] recovery = 23.8% (4993596/20953088) finish=1.2min speed=208066K/sec unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md6
/dev/md6:
Version : 1.2
Creation Time : Sun Aug 25 16:34:36 2019
Raid Level : raid6
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 4
Total Devices : 6
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:41:09 2019
State : clean, degraded, recovering
Active Devices : 2
Working Devices : 4
Failed Devices : 2
Spare Devices : 2 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Rebuild Status : 13% complete Name : localhost:6 (local to host localhost)
UUID : 7c3d15a2:4066f2c6:742f3e4c:82aae1bb
Events : 27 Number Major Minor RaidDevice State
5 8 97 0 spare rebuilding /dev/sdg1
4 8 81 1 spare rebuilding /dev/sdf1
2 8 49 2 active sync /dev/sdd1
3 8 65 3 active sync /dev/sde1 0 8 17 - faulty /dev/sdb1
1 8 33 - faulty /dev/sdc1

11.再次查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md6 : active raid6 sdg1[5] sdf1[4] sde1[3] sdd1[2] sdc1[1](F) sdb1[0](F)
41906176 blocks super 1.2 level 6, 512k chunk, algorithm 2 [4/4] [UUUU] unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md6
/dev/md6:
Version : 1.2
Creation Time : Sun Aug 25 16:34:36 2019
Raid Level : raid6
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 4
Total Devices : 6
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:42:42 2019
State : clean
Active Devices : 4
Working Devices : 4
Failed Devices : 2
Spare Devices : 0 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Name : localhost:6 (local to host localhost)
UUID : 7c3d15a2:4066f2c6:742f3e4c:82aae1bb
Events : 46 Number Major Minor RaidDevice State
5 8 97 0 active sync /dev/sdg1
4 8 81 1 active sync /dev/sdf1
2 8 49 2 active sync /dev/sdd1
3 8 65 3 active sync /dev/sde1 0 8 17 - faulty /dev/sdb1
1 8 33 - faulty /dev/sdc1

12.移除损坏的磁盘。

[root@localhost ~]# mdadm -r /dev/md6 /dev/sd{b,c}1
mdadm: hot removed /dev/sdb1 from /dev/md6
mdadm: hot removed /dev/sdc1 from /dev/md6
[root@localhost ~]# mdadm -D /dev/md6
/dev/md6:
Version : 1.2
Creation Time : Sun Aug 25 16:34:36 2019
Raid Level : raid6
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 4
Total Devices : 4
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:43:43 2019
State : clean
Active Devices : 4
Working Devices : 4
Failed Devices : 0
Spare Devices : 0 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Name : localhost:6 (local to host localhost)
UUID : 7c3d15a2:4066f2c6:742f3e4c:82aae1bb
Events : 47 Number Major Minor RaidDevice State
5 8 97 0 active sync /dev/sdg1
4 8 81 1 active sync /dev/sdf1
2 8 49 2 active sync /dev/sdd1
3 8 65 3 active sync /dev/sde1

13.重新添加热备份盘。

[root@localhost ~]# mdadm -a /dev/md6 /dev/sd{b,c}1
mdadm: added /dev/sdb1
mdadm: added /dev/sdc1
[root@localhost ~]# mdadm -D /dev/md6
/dev/md6:
Version : 1.2
Creation Time : Sun Aug 25 16:34:36 2019
Raid Level : raid6
Array Size : 41906176 (39.96 GiB 42.91 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 4
Total Devices : 6
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:44:01 2019
State : clean
Active Devices : 4
Working Devices : 6
Failed Devices : 0
Spare Devices : 2 Layout : left-symmetric
Chunk Size : 512K Consistency Policy : resync Name : localhost:6 (local to host localhost)
UUID : 7c3d15a2:4066f2c6:742f3e4c:82aae1bb
Events : 49 Number Major Minor RaidDevice State
5 8 97 0 active sync /dev/sdg1
4 8 81 1 active sync /dev/sdf1
2 8 49 2 active sync /dev/sdd1
3 8 65 3 active sync /dev/sde1 6 8 17 - spare /dev/sdb1
7 8 33 - spare /dev/sdc1

RAID10

RAID10是先将数据进行镜像操作,然后再对数据进行分组,RAID1在这里就是一个冗余的备份阵列,而RAID0则负责数据的读写阵列。至少要四块盘,两两组合做RAID1,然后做RAID0RAID10对存储容量的利用率和RAID1一样低,只有50%Raid10方案造成了50%的磁盘浪费,但是它提供了200%的速度和单磁盘损坏的数据安全性,并且当同时损坏的磁盘不在同一RAID1中,就能保证数据安全性,RAID10能提供比RAID5更好的性能。这种新结构的可扩充性不好,使用此方案比较昂贵。

实验RAID10创建,格式化,挂载使用,故障模拟,重新添加热备份。

1.添加420G的硬盘,分区,类型IDfd

[root@localhost ~]# fdisk -l | grep raid
/dev/sdb1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdc1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdd1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sde1 2048 41943039 20970496 fd Linux raid autodetect

2.创建两个RAID1,不添加热备份盘。

[root@localhost ~]# mdadm -C -v /dev/md101 -l1 -n2 /dev/sd{b,c}1
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 20953088K
Continue creating array? y
mdadm: Fail create md101 when using /sys/module/md_mod/parameters/new_array
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md101 started.
[root@localhost ~]# mdadm -C -v /dev/md102 -l1 -n2 /dev/sd{d,e}1
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 20953088K
Continue creating array? y
mdadm: Fail create md102 when using /sys/module/md_mod/parameters/new_array
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md102 started.

3.查看raidstat状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md102 : active raid1 sde1[1] sdd1[0]
20953088 blocks super 1.2 [2/2] [UU]
[=========>...........] resync = 48.4% (10148224/20953088) finish=0.8min speed=200056K/sec md101 : active raid1 sdc1[1] sdb1[0]
20953088 blocks super 1.2 [2/2] [UU]
[=============>.......] resync = 69.6% (14604672/20953088) finish=0.5min speed=200052K/sec unused devices: <none>
[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1]
md102 : active raid1 sde1[1] sdd1[0]
20953088 blocks super 1.2 [2/2] [UU] md101 : active raid1 sdc1[1] sdb1[0]
20953088 blocks super 1.2 [2/2] [UU] unused devices: <none>

4.查看两个RAID1的详细信息。

[root@localhost ~]# mdadm -D /dev/md101
/dev/md101:
Version : 1.2
Creation Time : Sun Aug 25 16:53:00 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:53:58 2019
State : clean, resyncing
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Consistency Policy : resync Resync Status : 62% complete Name : localhost:101 (local to host localhost)
UUID : 80bb4fc5:1a628936:275ba828:17f23330
Events : 9 Number Major Minor RaidDevice State
0 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
[root@localhost ~]# mdadm -D /dev/md102
/dev/md102:
Version : 1.2
Creation Time : Sun Aug 25 16:53:23 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:54:02 2019
State : clean, resyncing
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Consistency Policy : resync Resync Status : 42% complete Name : localhost:102 (local to host localhost)
UUID : 38abac72:74fa8a53:3a21b5e4:01ae64cd
Events : 6 Number Major Minor RaidDevice State
0 8 49 0 active sync /dev/sdd1
1 8 65 1 active sync /dev/sde1

5.创建RAID10

[root@localhost ~]# mdadm -C -v /dev/md10 -l0 -n2 /dev/md10{1,2}
mdadm: chunk size defaults to 512K
mdadm: Fail create md10 when using /sys/module/md_mod/parameters/new_array
mdadm: Defaulting to version 1.2 metadata
mdadm: array /dev/md10 started.

6.查看raidstat状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1] [raid0]
md10 : active raid0 md102[1] md101[0]
41871360 blocks super 1.2 512k chunks md102 : active raid1 sde1[1] sdd1[0]
20953088 blocks super 1.2 [2/2] [UU] md101 : active raid1 sdc1[1] sdb1[0]
20953088 blocks super 1.2 [2/2] [UU] unused devices: <none>

7.查看RAID10的详细信息。

[root@localhost ~]# mdadm -D /dev/md10
/dev/md10:
Version : 1.2
Creation Time : Sun Aug 25 16:56:08 2019
Raid Level : raid0
Array Size : 41871360 (39.93 GiB 42.88 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:56:08 2019
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Chunk Size : 512K Consistency Policy : none Name : localhost:10 (local to host localhost)
UUID : 23c6abac:b131a049:db25cac8:686fb045
Events : 0 Number Major Minor RaidDevice State
0 9 101 0 active sync /dev/md101
1 9 102 1 active sync /dev/md102

8.格式化。

[root@localhost ~]# mkfs.xfs /dev/md10
meta-data=/dev/md10 isize=512 agcount=16, agsize=654208 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=10467328, imaxpct=25
= sunit=128 swidth=256 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=5112, version=2
= sectsz=512 sunit=8 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0

9.挂载使用。

[root@localhost ~]# mkdir /mnt/md10
[root@localhost ~]# mount /dev/md10 /mnt/md10/
[root@localhost ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/centos-root xfs 17G 1014M 16G 6% /
devtmpfs devtmpfs 901M 0 901M 0% /dev
tmpfs tmpfs 912M 0 912M 0% /dev/shm
tmpfs tmpfs 912M 8.7M 903M 1% /run
tmpfs tmpfs 912M 0 912M 0% /sys/fs/cgroup
/dev/sda1 xfs 1014M 143M 872M 15% /boot
tmpfs tmpfs 183M 0 183M 0% /run/user/0
/dev/md10 xfs 40G 33M 40G 1% /mnt/md10

10.创建测试文件。

[root@localhost ~]# touch /mnt/md10/test{1..9}.txt
[root@localhost ~]# ls /mnt/md10/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

11.故障模拟。

[root@localhost ~]# mdadm -f /dev/md101 /dev/sdb1
mdadm: set /dev/sdb1 faulty in /dev/md101
[root@localhost ~]# mdadm -f /dev/md102 /dev/sdd1
mdadm: set /dev/sdd1 faulty in /dev/md102

12.查看测试文件。

[root@localhost ~]# ls /mnt/md10/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt

13.查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1] [raid0]
md10 : active raid0 md102[1] md101[0]
41871360 blocks super 1.2 512k chunks md102 : active raid1 sde1[1] sdd1[0](F)
20953088 blocks super 1.2 [2/1] [_U] md101 : active raid1 sdc1[1] sdb1[0](F)
20953088 blocks super 1.2 [2/1] [_U] unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md101
/dev/md101:
Version : 1.2
Creation Time : Sun Aug 25 16:53:00 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 17:01:11 2019
State : clean, degraded
Active Devices : 1
Working Devices : 1
Failed Devices : 1
Spare Devices : 0 Consistency Policy : resync Name : localhost:101 (local to host localhost)
UUID : 80bb4fc5:1a628936:275ba828:17f23330
Events : 23 Number Major Minor RaidDevice State
- 0 0 0 removed
1 8 33 1 active sync /dev/sdc1 0 8 17 - faulty /dev/sdb1
[root@localhost ~]# mdadm -D /dev/md102
/dev/md102:
Version : 1.2
Creation Time : Sun Aug 25 16:53:23 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 17:00:43 2019
State : clean, degraded
Active Devices : 1
Working Devices : 1
Failed Devices : 1
Spare Devices : 0 Consistency Policy : resync Name : localhost:102 (local to host localhost)
UUID : 38abac72:74fa8a53:3a21b5e4:01ae64cd
Events : 19 Number Major Minor RaidDevice State
- 0 0 0 removed
1 8 65 1 active sync /dev/sde1 0 8 49 - faulty /dev/sdd1
[root@localhost ~]# mdadm -D /dev/md10
/dev/md10:
Version : 1.2
Creation Time : Sun Aug 25 16:56:08 2019
Raid Level : raid0
Array Size : 41871360 (39.93 GiB 42.88 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 16:56:08 2019
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Chunk Size : 512K Consistency Policy : none Name : localhost:10 (local to host localhost)
UUID : 23c6abac:b131a049:db25cac8:686fb045
Events : 0 Number Major Minor RaidDevice State
0 9 101 0 active sync /dev/md101
1 9 102 1 active sync /dev/md102

14.移除损坏的磁盘。

[root@localhost ~]# mdadm -r /dev/md101 /dev/sdb1
mdadm: hot removed /dev/sdb1 from /dev/md101
[root@localhost ~]# mdadm -r /dev/md102 /dev/sdd1
mdadm: hot removed /dev/sdd1 from /dev/md102
[root@localhost ~]# mdadm -D /dev/md101
/dev/md101:
Version : 1.2
Creation Time : Sun Aug 25 16:53:00 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 1
Persistence : Superblock is persistent Update Time : Sun Aug 25 17:04:59 2019
State : clean, degraded
Active Devices : 1
Working Devices : 1
Failed Devices : 0
Spare Devices : 0 Consistency Policy : resync Name : localhost:101 (local to host localhost)
UUID : 80bb4fc5:1a628936:275ba828:17f23330
Events : 26 Number Major Minor RaidDevice State
- 0 0 0 removed
1 8 33 1 active sync /dev/sdc1
[root@localhost ~]# mdadm -D /dev/md102
/dev/md102:
Version : 1.2
Creation Time : Sun Aug 25 16:53:23 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 1
Persistence : Superblock is persistent Update Time : Sun Aug 25 17:05:07 2019
State : clean, degraded
Active Devices : 1
Working Devices : 1
Failed Devices : 0
Spare Devices : 0 Consistency Policy : resync Name : localhost:102 (local to host localhost)
UUID : 38abac72:74fa8a53:3a21b5e4:01ae64cd
Events : 20 Number Major Minor RaidDevice State
- 0 0 0 removed
1 8 65 1 active sync /dev/sde1

15.重新添加热备份盘。

[root@localhost ~]# mdadm -a /dev/md101 /dev/sdb1
mdadm: added /dev/sdb1
[root@localhost ~]# mdadm -a /dev/md102 /dev/sdd1
mdadm: added /dev/sdd1

16.再次查看状态。

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1] [raid0]
md10 : active raid0 md102[1] md101[0]
41871360 blocks super 1.2 512k chunks md102 : active raid1 sdd1[2] sde1[1]
20953088 blocks super 1.2 [2/1] [_U]
[====>................] recovery = 23.8% (5000704/20953088) finish=1.2min speed=208362K/sec md101 : active raid1 sdb1[2] sdc1[1]
20953088 blocks super 1.2 [2/1] [_U]
[======>..............] recovery = 32.0% (6712448/20953088) finish=1.1min speed=203407K/sec unused devices: <none>
[root@localhost ~]# cat /proc/mdstat
Personalities : [raid1] [raid0]
md10 : active raid0 md102[1] md101[0]
41871360 blocks super 1.2 512k chunks md102 : active raid1 sdd1[2] sde1[1]
20953088 blocks super 1.2 [2/2] [UU] md101 : active raid1 sdb1[2] sdc1[1]
20953088 blocks super 1.2 [2/2] [UU] unused devices: <none>
[root@localhost ~]# mdadm -D /dev/md101
/dev/md101:
Version : 1.2
Creation Time : Sun Aug 25 16:53:00 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 17:07:28 2019
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Consistency Policy : resync Name : localhost:101 (local to host localhost)
UUID : 80bb4fc5:1a628936:275ba828:17f23330
Events : 45 Number Major Minor RaidDevice State
2 8 17 0 active sync /dev/sdb1
1 8 33 1 active sync /dev/sdc1
[root@localhost ~]# mdadm -D /dev/md102
/dev/md102:
Version : 1.2
Creation Time : Sun Aug 25 16:53:23 2019
Raid Level : raid1
Array Size : 20953088 (19.98 GiB 21.46 GB)
Used Dev Size : 20953088 (19.98 GiB 21.46 GB)
Raid Devices : 2
Total Devices : 2
Persistence : Superblock is persistent Update Time : Sun Aug 25 17:07:36 2019
State : clean
Active Devices : 2
Working Devices : 2
Failed Devices : 0
Spare Devices : 0 Consistency Policy : resync Name : localhost:102 (local to host localhost)
UUID : 38abac72:74fa8a53:3a21b5e4:01ae64cd
Events : 39 Number Major Minor RaidDevice State
2 8 49 0 active sync /dev/sdd1
1 8 65 1 active sync /dev/sde1

常用 RAID 间比较

名称 硬盘数量 容量/利用率 读性能 写性能 数据冗余
RAID0 N N块总和 N倍 N倍 无,一个故障,丢失所有数据
RAID1 N(偶数) 50% 写两个设备,允许一个故障
RAID5 N≥3 (N-1)/N ↑↑ 计算校验,允许一个故障
RAID6 N≥4 (N-2)/N ↑↑ ↓↓ 双重校验,允许两个故障
RAID10 N(偶数,N≥4) 50% (N/2)倍 (N/2)倍 允许基组中的磁盘各损坏一个

一些话

此篇涉及到的操作很简单,但是,有很多的查看占用了大量的篇幅,看关键点,过程都是一个套路,都是重复的。

Linux 常见 RAID 及软 RAID 创建的更多相关文章

  1. 硬RAID和软RAID

    RAID简介: RAID是 Redundant Array of Independent Disks的简写,意为独立磁盘冗余阵列,简称磁盘阵列.基本思想是把多个相对便宜的硬盘结合起来,称为一个磁盘阵列 ...

  2. 硬RAID与软RAID的区别

    什么是RAID? RAID是英文Redundant Array of Independent Disks的缩写,翻译成中文即为独立磁盘冗余阵列,或简称磁盘阵列.简单的说,RAID是一种把多块独立的硬盘 ...

  3. linux磁盘管理系列-软RAID的实现

    1 什么是RAID RAID全称是独立磁盘冗余阵列(Redundant Array of Independent Disks),基本思想是把多个磁盘组合起来,组合一个磁盘阵列组,使得性能大幅提高. R ...

  4. RAID、软RAID和硬RAID

    RAID(redundant array of inexpensive disks):独立的硬盘冗余阵列,基本思想是把多个小硬盘组合在一起成为一个磁盘组,通过软件或硬件的管理达到性能提升或容量增大或增 ...

  5. 图例演示在Linux上快速安装软RAID的详细步骤

    物理环境:虚拟机centos6.4 配置:8G内存.2*2核cpu.3块虚拟硬盘(sda,sdb,sdc,sdb和sdc是完全一样的)        在实际生产环境中,系统硬盘与数据库和应用是分开的, ...

  6. LINUX中软RAID的实现方案

    转自linux就该这么学 应用场景 Raid大家都知道是冗余磁盘的意思(Redundant Arrays of Independent Disks,RAID),可以按业务系统的需要提供高可用性和冗余性 ...

  7. 软RAID 0的技术概要及实现

    1 什么是RAID,RAID的级别和特点 : 什么是RAID呢?全称是 “A Case for Redundant Arrays of Inexpensive Disks (RAID)”,在1987年 ...

  8. 软RAID管理

    软RAID管理 软RAID 软RAID 提供管理界面:mdadm 软RAID为空余磁盘添加冗余,结合了内核中的md(multi devices). RAID 设备可命名为/dev/md0./dev/m ...

  9. 软RAID和硬RAID的区别

    要实现RAID可以分为硬件实现和软件实现两种.所谓硬RAID就是指通过硬件实现,同理软件实现就作为软RAID.   硬RAID 就是用专门的RAID控制器将硬盘和电脑连接起来,RAID控制器负责将所有 ...

随机推荐

  1. MSSQL附加数据库时提示以下错误: 无法打开物理文件“***.mdf”。操作系统错误 5:“5(拒绝访问。)”。 (Microsoft SQL Server,错误: 5120)

    MSSQL附加数据库时提示以下错误: 无法打开物理文件“***.mdf”.操作系统错误 5:“5(拒绝访问.)”. (Microsoft SQL Server,错误: 5120) ***** 解决方法 ...

  2. Apache限制IP并发数和流量控制

    使用mod_limitipconn模块限制IP并发连接数安装: wget http://dominia.org/djao/limit/mod_limitipconn-0.24.tar.bz2 tar ...

  3. 设计模式php+java版本(1) 基础篇 七大原则

    2019年9月6日11:15:46 关于设计模式,其实就是编程思想的一个体现,有比较完善的编程思想写出的项目代码和没有编程思想的写出的差距巨大,代码的可读性,可维护性,可扩展性天差地别,有些刚接触的编 ...

  4. win7安装 truffle

    1. 最近有个项目需要用到区块链,第一次玩不太熟悉.现在电脑上安装个  truffle,作为一个区块链节点 2. 安装 truffle ,之前需要安装其他几个软件 truffle的安装需要首先装有:n ...

  5. Properties的有序读写

    使用java.util.Properties提供的类,读取properties文件的时候,读出来的是乱序的 如下边的情况 import java.io.*; import java.util.Arra ...

  6. Spring计时器StopWatch使用

    我们可以利用已有的工具类中的秒表,常见的秒表工具类有org.springframework.util.StopWatch.org.apache.commons.lang.time.StopWatch以 ...

  7. 题解 CF53E 【Dead Ends】

    题意: 给一个n(n<=10)个节点的无向图,图里面有m条边,以这m条边构建生成树,求所有生成树中只含有k个度数为1的点的方案数. 题解: 看见这个数量级就一定会想到状态压缩dp... 那让我们 ...

  8. java知识精要(一)

    一.java数组 (疯狂java讲义 第4.5 ~ 4.6章节) 1) 声明形式: type[] arrayName; 推荐方式 type arrayName[]; 2) 初始化: 方式一: type ...

  9. [UOJ #393]【NOI2018】归程

    题目大意:有一张$n$个点$m$条边的图,每个边有两个属性$a_i,b_i$.有$Q$个询问,每个询问给出$v,p$,表示所有边中$b_i\leqslant p$的边会被标记,在点$v$,可以通过不被 ...

  10. [cf 1236 E] Alice and the Unfair Game

    题意: 给定一个长度为m的序列$A$,你有一个长度为n的棋盘,可以任选一个位置x作为起点. 在时刻$[1,m+1]$你可以向左或向右移动一格. 设时刻i你移动后所在的位置为$B_i$,你需要满足对于任 ...