Linux磁盘扩容

上一篇文章https://www.cnblogs.com/zh-dream/p/12683071.html已经对一块盘进行了 分区、创建文件系统、挂载本文展示如何以分区磁盘进行扩容

我们先看分区表格式

[root@master ~]# fdisk -lu /dev/sdb

Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x45ef390c

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048     4196351     2097152   83  Linux

再查看分区的文件系统类型

只有创建了文件系统的分区才会有返回结果

[root@master ~]# fdisk -lu /dev/sdc

Disk /dev/sdc: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xeed0d630

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1            2048    10487807     5242880   83  Linux
/dev/sdc2        10487808    14682111     2097152   83  Linux
[root@master
~]# blkid /dev/sdc2 ## 由于未创建文件系统,并没有输出
[root@master
~]# blkid /dev/sdc1 /dev/sdc1: UUID="9399025f-d5ca-4951-b90a-92e5141f7e7d" TYPE="ext4"

检查文件系统状态

[root@master ~]# echo 123 >/data/num

[root@master ~]# xfs_repair  /dev/sdb1
xfs_repair: /dev/sdb1 contains a mounted filesystem
xfs_repair: /dev/sdb1 contains a mounted and writable filesystem

fatal error -- couldn't initialize XFS library


[root@master ~]# xfs_repair /dev/sdb1
Phase 1 - find and verify superblock...                    
Phase 2 - using internal log                                  
        - zero log...
        - scan filesystem freespace and inode maps...
        - found root inode chunk
Phase 3 - for each AG...
        - scan and clear agi unlinked lists...
        - process known inodes and perform inode discovery...
        - agno = 0
        - agno = 1
        - agno = 2
        - agno = 3
        - process newly discovered inodes...
Phase 4 - check for duplicate blocks...
        - setting up duplicate extent list...
        - check for inodes claiming duplicate blocks...
        - agno = 0
        - agno = 1
        - agno = 2
        - agno = 3
Phase 5 - rebuild AG headers and trees...
        - reset superblock...
Phase 6 - check inode connectivity...
        - resetting contents of realtime bitmap and summary inodes
        - traversing filesystem ...
        - traversal finished ...
        - moving disconnected inodes to lost+found ...
Phase 7 - verify and correct link counts...                           
done

xfs_repair执行结果解释

1、获取并检查超块信息,如果没有找到超块数据,就结束

2、检查AG头结构信息(AGI,AGF和AGFL)并扫描AGF和AGI btree。

3、使用第2阶段的AGI b+tree,扫描inode树,处理已删除的inode的未链接列表,并查找可能缺少的inode集群。
遍历查找所有的inode,记录使用过的文件系统块(extents)。
对于目录inode,扫描目录结构并查找丢失的inode信息。
所有错误的inode数据都会被删除,包括不可恢复的损坏目录

4、再次扫描inode extents。具有覆盖已使用数据的范围的任何inode都将被删除

5、无论是否发现错误,都会重建AG头结构数据,包括AGI b+tree,AGF b+tree和AGFL。
实时inode也被重建。

6、该阶段,文件系统会处于挂载状态,xfs_repair使用libxfs_mount挂载,修复过程是处于一个挂载状态下执行的,程序会分给它一个挂载入口。
通过扫描分析所有数据的目录。
(1)任何有一定损坏的目录都会用任何可以恢复的条目重建。
(2)重新创建缺少的根目录。
(3)目标中的所有inode都标记为reached.。
最后,所有状态为unreached的inode都会被放到lost+found目录下。

lost+found目录的文件通常是未链接的文件(名字以及被删除),这些文件还被一些进程使用(数据没有删除),比如系统突然关机时(内核panic或突然断电)出现。这些文件会被系统删除。

7、根据阶段6收集的数据修复inode的nlinks

注意:如果之前在/etc/fstab中写入了待扩容分区的自动挂载信息,请务必将其注释掉,以免操作的时候系统突然掉电,出现异常。出现的异常见https://www.cnblogs.com/zh-dream/p/12683769.html

fdisk删除已有分区

查看挂载情况

如果有挂载,请先umount卸载,在执行后面的操作

[root@master ~]# mount|grep /dev/sdc

删除已有分区

[root@master ~]# fdisk /dev/sdc
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


Command (m for help): p

Disk /dev/sdc: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x45ef390c

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1            2048     4196351     2097152   83  Linux

Command (m for help): d
Selected partition 1
Partition 1 is deleted

Command (m for help): p

Disk /dev/sdc: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x45ef390c

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

 扩容分区

[root@master ~]# fdisk /dev/sdb
Welcome to fdisk (util-linux 2.23.2).

Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.


Command (m for help): p

Disk /dev/sdb: 21.5 GB, 21474836480 bytes, 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x45ef390c

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): n
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): 
Using default response p
Partition number (1-4, default 1): 
First sector (2048-41943039, default 2048): 
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039): 
Using default value 41943039
Partition 1 of type Linux and of size 20 GiB is set

Command (m for help): w
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.

通知内核分区表已更改

[root@master ~]# partprobe /dev/sdb
[root@master ~]# lsblk /dev/sdb
NAME   MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sdb      8:16   0  20G  0 disk 
└─sdb1   8:17   0  20G  0 part 

扩容文件系统

xfs文件系统:先挂载,在扩容

[root@master ~]# mount /dev/sdb1 /data
[root@master ~]# ll /data
total 4
-rw-r--r--. 1 root root 4 Apr 11 23:48 num

[root@master ~]# xfs_growfs /dev/sdb1
meta-data=/dev/sdb1              isize=512    agcount=4, agsize=131072 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=524288, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=2560, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 524288 to 5242624

对于ext类型的文件系统扩容:先扩容文件系统,再挂载

[root@master ~]# resize2fs /dev/sdb1
resize2fs 1.42.9 (28-Dec-2013)
The filesystem is already 5242624 blocks long.  Nothing to do!

[root@master ~]# mount /dev/sdb1 /data
原文地址:https://www.cnblogs.com/zh-dream/p/12683414.html