RAID5 and LVM are used in combination

Catalog

One , Add hard disk

  Two , Create a disk array

  3、 ... and , establish LVM

  test ,

1, First look at it. raid Can the disk array perform the most basic operations

2, Test if you can lvm Capacity expansion ,​ edit

 3, Test after simulating the damage of a hard disk

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One , Add hard disk

  Two , Create a disk array

  Use mdadm  -D  /dev/md5

  3、 ... and , establish LVM

Input pvcreate /dev/md5 To create physical volumes /dev/md5
Input vgcreate myvg /dev/md5 To create a volume group myvg
Input lvcreate  -L  200M  -n /dev/rr5/dd5 To create Logic volume vo

 

  Format logical volumes , Pay attention to When formatting logical volumes , Use ext file system , The size of logical volumes can be increased or decreased , While using xfs File system , Can only increase but not decrease , So here we choose ext4 Format the file system

 

  Mount to /drr Under the table of contents

  test ,

1, First look at it. raid Can the disk array perform the most basic operations

2, Test if you can lvm Capacity expansion ,

 3, Test after simulating the damage of a hard disk

  Use ,mdadm /dev/md5 -f /dev/sdg1

  You can see , Because we first added a hot spare , Therefore, when one of the three working disks fails , The idle hot spare will be filled up immediately , Thus, it plays a better role in data protection . When the hot spare disk is added ,spare Device The following number will change to 0, It means that there is no hot spare now .
Since the hard disk sde Has been damaged , We need to remove it from the array

  Remove sde after , because raid The disk array is not affected , Therefore, it is possible to perform various operations on the files in the disk , The previous data has not been lost due to the damage of a hard disk

  There is no hot spare now , Let's delete one again , See if the data can still be used

  You can still watch

  Because we have established four disks . Add a hot disk , So damage a disk , It doesn't affect

There will also be redundancy , When three pieces are damaged

  Then you will find , When three discs are damaged at the same time , Whole raid The array will be damaged , Then it will become read-only mode