2021-05-12 14:32:11
Linux 常見 RAID 及軟 RAID 建立
2020-06-16 16:32:38
RAID可以大幅度的提高磁碟效能，以及可靠性，這麼好的技術怎麼能不掌握呢！此篇介紹一些常見RAID，及其在Linux上的軟RAID建立方法。
mdadm#
- 建立軟
RAID
mdadm -C -v /dev/建立的裝置名 -l級別 -n數量 新增的磁碟 [-x數量 新增的熱備份盤]-C：建立一個新的陣列--create-v：顯示細節--verbose-l：設定RAID級別--level=-n：指定陣列中可用device數目--raid-devices=-x：指定初始陣列的富餘device數目--spare-devices=，空閒盤（熱備磁碟）能在工作盤損壞後自動頂替
- 檢視詳細資訊
mdadm -D /dev/裝置名-D：列印一個或多個md device的詳細資訊--detail
- 檢視
RAID的狀態
cat /proc/mdstat- 模擬損壞
mdadm -f /dev/裝置名 磁碟-f：模擬損壞fail
- 移除損壞
mdadm -r /dev/裝置名 磁碟-r：移除remove
- 新增新硬碟作為熱備份盤
mdadm -a /dev/裝置名 磁碟-a：新增add
RAID0#
RAID0俗稱條帶，它將兩個或多個硬碟組成一個邏輯硬碟，容量是所有硬碟之和，因為是多個硬碟組合成一個，故可並行寫操作，寫入速度提高，但此方式硬碟資料沒有冗餘，沒有容錯，一旦一個物理硬碟損壞，則所有資料均丟失。因而，RAID0適合於對資料量大，但安全性要求不高的場景，比如音像、視訊檔的儲存等。
實驗：RAID0建立，格式化，掛載使用。
1.新增2塊20G的硬碟，分割區，型別ID為fd。
[root@localhost ~]# fdisk -l | grep raid
/dev/sdb1 2048 41943039 20970496 fd Linux raid autodetect
/dev/sdc1 2048 41943039 20970496 fd Linux raid autodetect2.建立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.檢視raidstat狀態。
[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.檢視RAID0的詳細資訊。
[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/sdc15.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=06.掛載使用。
[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/md0RAID1#
RAID1俗稱映象，它最少由兩個硬碟組成，且兩個硬碟上儲存的資料均相同，以實現資料冗餘。RAID1讀操作速度有所提高，寫操作理論上與單硬碟速度一樣，但由於資料需要同時寫入所有硬碟，實際上稍為下降。容錯性是所有組合方式裡最好的，只要有一塊硬碟正常，則能保持正常工作。但它對硬碟容量的利用率則是最低，只有50%，因而成本也是最高。RAID1適合對資料安全性要求非常高的場景，比如儲存資料庫資料檔案之類。
實驗：RAID1建立，格式化，掛載使用，故障模擬，重新新增熱備份。
1.新增3塊20G的硬碟，分割區，型別ID為fd。
[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 autodetect2.建立RAID1，並新增1個熱備份盤。
[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.檢視raidstat狀態。
[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.檢視RAID1的詳細資訊。
[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/sdd15.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=06.掛載使用。
[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/md17.建立測試檔案。
[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.txt8.故障模擬。
[root@localhost ~]# mdadm -f /dev/md1 /dev/sdb1
mdadm: set /dev/sdb1 faulty in /dev/md19.檢視測試檔案。
[root@localhost ~]# ls /mnt/md1/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt10.檢視狀態。
[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/sdb111.再次檢視狀態。
[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/sdb112.移除損壞的磁碟
[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/sdc113.重新新增熱備份盤。
[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/sdb1RAID5#
RAID5最少由三個硬碟組成，它將資料分散儲存於陣列中的每個硬碟，並且還伴有一個資料校驗位，資料位與校驗位通過演算法能相互驗證，當丟失其中的一位時，RAID控制器能通過演算法，利用其它兩位資料將丟失的資料進行計算還原。因而RAID5最多能允許一個硬碟損壞，有容錯性。RAID5相對於其它的組合方式，在容錯與成本方面有一個平衡，因而受到大多數使用者的歡迎。一般的磁碟陣列，最常使用的就是RAID5這種方式。
實驗：RAID5建立，格式化，掛載使用，故障模擬，重新新增熱備份。
1.新增4塊20G的硬碟，分割區，型別ID為fd。
[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 autodetect2.建立RAID5，並新增1個熱備份盤。
[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.檢視raidstat狀態。
[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.檢視RAID5的詳細資訊。
[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/sde15.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=06.掛載使用。
[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/md57.建立測試檔案。
[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.txt8.故障模擬。
[root@localhost ~]# mdadm -f /dev/md5 /dev/sdb1
mdadm: set /dev/sdb1 faulty in /dev/md59.檢視測試檔案。
[root@localhost ~]# ls /mnt/md5/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt10.檢視狀態。
[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/sdb111.再次檢視狀態。
[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/sdb112.移除損壞的磁碟。
[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/sdd113.重新新增熱備份盤。
[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/sdb1RAID6#
RAID6是在RAID5的基礎上改良而成的，RAID6再將資料校驗位增加一位，所以允許損壞的硬碟數量也由 RAID5的一個增加到二個。由於同一陣列中兩個硬碟同時損壞的概率非常少，所以，RAID6用增加一塊硬碟的代價，換來了比RAID5更高的資料安全性。
實驗：RAID6建立，格式化，掛載使用，故障模擬，重新新增熱備份。
1.新增6塊20G的硬碟，分割區，型別ID為fd。
[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 autodetect2.建立RAID6，並新增2個熱備份盤。
[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.檢視raidstat狀態。
[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.檢視RAID6的詳細資訊。
[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/sdg15.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=06.掛載使用。
[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/md67.建立測試檔案。
[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.txt8.故障模擬。
[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/md69.檢視測試檔案。
[root@localhost ~]# ls /mnt/md6/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt10.檢視狀態。
[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/sdc111.再次檢視狀態。
[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/sdc112.移除損壞的磁碟。
[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/sde113.重新新增熱備份盤。
[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/sdc1RAID10#
RAID10是先將資料進行映象操作，然後再對資料進行分組，RAID1在這裡就是一個冗餘的備份陣列，而RAID0則負責資料的讀寫陣列。至少要四塊盤，兩兩組合做RAID1，然後做RAID0，RAID10對儲存容量的利用率和RAID1一樣低，只有50%。Raid10方案造成了50%的磁碟浪費，但是它提供了200%的速度和單磁碟損壞的資料安全性，並且當同時損壞的磁碟不在同一RAID1中，就能保證資料安全性，RAID10能提供比RAID5更好的效能。這種新結構的可擴充性不好，使用此方案比較昂貴。
實驗：RAID10建立，格式化，掛載使用，故障模擬，重新新增熱備份。
1.新增4塊20G的硬碟，分割區，型別ID為fd。
[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 autodetect2.建立兩個RAID1，不新增熱備份盤。
[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.檢視raidstat狀態。
[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.檢視兩個RAID1的詳細資訊。
[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/sde15.建立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.檢視raidstat狀態。
[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.檢視RAID10的詳細資訊。
[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/md1028.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=09.掛載使用。
[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/md1010.建立測試檔案。
[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.txt11.故障模擬。
[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/md10212.檢視測試檔案。
[root@localhost ~]# ls /mnt/md10/
test1.txt test2.txt test3.txt test4.txt test5.txt test6.txt test7.txt test8.txt test9.txt13.檢視狀態。
[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/md10214.移除損壞的磁碟。
[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/sde115.重新新增熱備份盤。
[root@localhost ~]# mdadm -a /dev/md101 /dev/sdb1
mdadm: added /dev/sdb1
[root@localhost ~]# mdadm -a /dev/md102 /dev/sdd1
mdadm: added /dev/sdd116.再次檢視狀態。
[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 間比較#
| 名稱 | 硬碟數量 | 容量/利用率 | 讀效能 | 寫效能 | 資料冗餘 |
|---|---|---|---|---|---|
| RAID0 | N | N塊總和 | N倍 | N倍 | 無，一個故障，丟失所有資料 |
| RAID1 | N（偶數） | 50% | ↑ | ↓ | 寫兩個裝置，允許一個故障 |
| RAID5 | N≥3 | (N-1)/N | ↑↑ | ↓ | 計算校驗，允許一個故障 |
| RAID6 | N≥4 | (N-2)/N | ↑↑ | ↓↓ | 雙重校驗，允許兩個故障 |
| RAID10 | N（偶數，N≥4） | 50% | (N/2)倍 | (N/2)倍 | 允許基組中的磁碟各損壞一個 |
一些話#
此篇涉及到的操作很簡單，但是，有很多的檢視占用了大量的篇幅，看關鍵點，過程都是一個套路，都是重複的。
相關文章