Raid configuration in linux

I recently learned how to configure raid in linux as follows:
1. Preliminary work
Change the system id of the partition to fd.
2. raid
Mdadm-C/dev/md2-l 5-n 3/dev/sdb8/dev/sdb9/dev/sdb10
-C is the name specified for creating a raid volume/dev/md2
-L the specified raid level is also a raid type.
-N: specify several devices (partition or hard disk) to create a raid volume.
3. view the raid volume status
# Cat/proc/mdstat
[Root @ client/] # cat/proc/mdstat
Personalities: [raid1] [raid6] [raid5] [raid4]
Md2: active raid5 sdb10 [2] sdb9 [1] sdb8 [0]
③ 208640 blocks level 5, 64 k chunk, algorithm 2 [3/3] [UUU]
① Md0: active raid1 sdb7 [2] (S) sdb6 [1] sdb5 [0]
② 200640 blocks [2/2] [UU]
Row ① indicates that md0 is RAID 1 and uses sdb7 sdb6 sdb5 to form four partitions. The numbers in the [] after each partition are in the RAID order. The S after sdb7 indicates that sdb7 is spare (hot spare disk)
Row ② indicates that the raid array has 208640 blocks (each block is 1 kb), so the total capacity is 200 MB. [M/n] indicates that the array requires m devices, n devices are running normally. The following [UU] indicates the startup status of all m devices, and U indicates normal. If it is "_", it indicates abnormal. ③ The raid5 array has "level 5, the 64 k chunk and algorithm 2 fields are represented as "RAID 5-level arrays, the size of the chunk written to the disk is 64 KB, and the algorithm 2 full-column algorithm is used.
 
Or run the command to view the raid status.
# Mdadm -- detail/dev/md0
4. Replace bad Disk
Shutdown -- change disk -- start -- Run Command
# Mdadm-a/dev/md0/dev/sdb // Add new hard disk sdb like md0raid volume
1. Create a New partition and run the partprobe command to make the new partition take effect immediately.
2. Remove the problematic disk and add a new hard disk partition.
# Mdadm -- mange/dev/md0-a/dev/sab7 -- remove/dev/sdb6
5. In many versions of linux, You can query the physical location of/dev/md [0-9] by yourself, and then set the required functions when starting the system.
However, it is recommended that you modify the configuration file yourself.
[Root @ client/] # mdadm -- detail/dev/md0 | grep-I uuid
UUID: f94014e0: 830c2c51: e8e063b6: 206e09a4
// UUID: the UUID that the device registers with the system.
# Vim/etc/mdadm. conf add a line here
ARRAY/dev/md0 UUID = f94014e0: 830c2c51: e8e063b6: 206e09a4
6. Delete raid
# Mdadm -- stop/dev/md0
# Cat/proc/mdstat view the raid0 status
# Vim/etcmdadm. conf: delete related information
# Vim/etc/fstab Delete related information
Author: "New network subnet"