Migrate /home partition

Experimental environment

Originally installed by the company Centos The server adopts the scheme of automatic partition , With the increasing number of system users using servers , The root partition often faces disk space exhaustion , There were even several times that the system could not start , To solve these problems , Now we need to add a new piece for the server scsl Hard disk , And put the user directory /home Migrate the data from to this hard disk , It is required that the use of the original user account cannot be affected after the migration .

Requirements describe

Add a piece to the virtual machine 80GB Of SCSI disk

Create a new hard drive 20GB The partition , It is used to store all ordinary user host folders

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        command ( Input  m  get help )：n
       
       
Partition type:
       
       
   p   primary (0 primary, 0 extended, 4 free)
       
       
   e   extended
       
       
Select (default p): p
       
       
 Zone number  (1-4, Default  1)：1
       
       
 start   A sector  (2048-167772159, The default is  2048)：
       
       
 The default value... Will be used  2048
       
       
Last  A sector , + A sector  or +size{K,M,G} (2048-167772159, The default is  167772159)：+20G
       
       
 Partition  1  Set to  Linux  type , The size is set to  20 GiB
       
       

       
       
 command ( Input  m  get help )：p
       
       

       
       
 disk  /dev/sdb：85.9 GB, 85899345920  byte ,167772160  Sectors 
       
       
Units =  A sector  of 1 * 512 = 512 bytes
       
       
 Sector size ( Logic / Physics )：512  byte  / 512  byte 
       
       
I/O  size ( Minimum / The best )：512  byte  / 512  byte 
       
       
 Disk label type ：dos
       
       
 Disk identifier ：0x47dca76d
       
       

       
       
    equipment  Boot      Start         End      Blocks   Id  System
       
       
/dev/sdb1            2048    41945087    20971520   83  Linux
       
       

       
       
 command ( Input  m  get help )：w
       
       
The partition table has been altered!
       
       

       
       
Calling ioctl() to re-read partition table.
       
       
 Synchronizing disk .
      
      
      
      

       
       
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After partition, the disk needs to be formatted

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       [[email protected] ~]# mkfs -t ext4 /dev/sdb1
       
       
mke2fs 1.42.9 (28-Dec-2013)
       
       
 File system tags =
       
       
OS type: Linux
       
       
 Block size =4096 (log=2)
       
       
 Block size =4096 (log=2)
       
       
Stride=0 blocks, Stripe width=0 blocks
       
       
1310720 inodes, 5242880 blocks
       
       
262144 blocks (5.00%) reserved for the super user
       
       
 The first data block =0
       
       
Maximum filesystem blocks=2153775104
       
       
160 block groups
       
       
32768 blocks per group, 32768 fragments per group
       
       
8192 inodes per group
       
       
Superblock backups stored on blocks: 
       
       
  32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208, 
       
       
  4096000
       
       

       
       
Allocating group tables:  complete                             
       
       
 Are written to the inode surface :  complete                             
       
       
Creating journal (32768 blocks):  complete 
       
       
Writing superblocks and filesystem accounting information:  complete    
       
       

       
       
[[email protected] ~]#
      
      
      
      

       
       
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The new partition is still mounted to /home Under the table of contents , You need to import the data of the original user in the system

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       [[email protected] ~]# mkdir /zhang
       
       
[[email protected] ~]# mv /home/* -t /zhang/
       
       
[[email protected] ~]# ls /zhang/
       
       
bdqn  kylin  obama  zhang
       
       
[[email protected] ~]# ls /home/
       
       
[[email protected] ~]# mount /dev/sdb1 /home/
       
       
[[email protected] ~]# df
       
       
 file system           1K- block      Already used       You can use   Already used %  Mount point 
       
       
devtmpfs         481616       0   481616    0% /dev
       
       
tmpfs            497836       0   497836    0% /dev/shm
       
       
tmpfs            497836    8676   489160    2% /run
       
       
tmpfs            497836       0   497836    0% /sys/fs/cgroup
       
       
/dev/sda3      18873344 5782856 11349848   34% /
       
       
/dev/sda1       1038336  173828   864508   17% /boot
       
       
tmpfs             99568      24    99544    1% /run/user/0
       
       
/dev/sr0        4600876 4600876        0  100% /run/media/root/CentOS 7 x86_64
       
       
/dev/sdb1      20511312   45080 19401272    1% /home
       
       
[[email protected] ~]# ls -al /home/
       
       
 Total usage  20
       
       
drwxr-xr-x  3 root root  4096 7 month    4 15:31 .
       
       
dr-xr-xr-x. 1 root root   230 7 month    4 15:33 ..
       
       
drwx------  2 root root 16384 7 month    4 15:31 lost+found
       
       
[[email protected] ~]# mv /zhang/* -t /home/
      
      
      
      

       
       
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The server can automatically mount the partition after each boot

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       [[email protected] ~]# vim /etc/fstab
      
      
      
      

       
       
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Check the partition after restart