代码收藏家 CentOS根目录扩容详细教程：亲测可用
亲测好用
一、问题与目的
原因是磁盘空间已满，正好有时间，研究一下怎么对Centos进行扩容
二、解决方法
1、首先，通过命令df -h 观察磁盘占用情况
可以发现根目录已经被写满了，这会导致所有写操作都无法进行
2、先关闭虚拟机，然后在VMware的设置中选择添加一块新的硬盘（一直点下一步就可以了）
我选择了扩容40G
3、重启虚拟机后通过命令lsblk可以发现多了一个分区sdb（原来只有sda）
所以接下来对sdb进行分区操作
4、对sdb进行分区操作
1.[root@itcast ~]# fdisk /dev/sdb
2.Welcome to fdisk (util-linux 2.23.2).
3.
4.Changes will remain in memory only, until you decide to write them.
5.Be careful before using the write command.
6.
7.Device does not contain a recognized partition table
8.Building a new DOS disklabel with disk identifier 0xdeeb604b.
9.
10.Command (m for help): m #这个是帮助 可忽略
11.Command action
12. a toggle a bootable flag
13. b edit bsd disklabel
14. c toggle the dos compatibility flag
15. d delete a partition
16. g create a new empty GPT partition table
17. G create an IRIX (SGI) partition table
18. l list known partition types
19. m print this menu
20. n add a new partition
21. o create a new empty DOS partition table
22. p print the partition table
23. q quit without saving changes
24. s create a new empty Sun disklabel
25. t change a partition's system id
26. u change display/entry units
27. v verify the partition table
28. w write table to disk and exit
29. x extra functionality (experts only)
31.Command (m for help): n #输入n新建一个分区
32.Partition type:
33. p primary (0 primary, 0 extended, 4 free)
34. e extended
35.Select (default p): p #输入p,将分区创建为主分区
36.Partition number (1-4, default 1): 1
37.First sector (2048-83886079, default 2048): #默认 回车
38.Using default value 2048
39.Last sector, +sectors or +size{K,M,G} (2048-83886079, default 83886079):
40.Using default value 83886079
41.Partition 1 of type Linux and of size 40 GiB is set
42.
43.Command (m for help): t #输入t改变分区类型
44.Selected partition 1
45.Hex code (type L to list all codes): 8e #输入8e对应LVM
46.Changed type of partition 'Linux' to 'Linux LVM'
47.
48.Command (m for help): w #保存
49.The partition table has been altered!
50.
51.Calling ioctl() to re-read partition table.
52.Syncing disks.
53.
再次观察发现有了sdb1分区
1.[root@itcast ~]# lsblk
2.NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
3.sda 8:0 0 40G 0 disk
4.├─sda1 8:1 0 200M 0 part /boot
5.└─sda2 8:2 0 39.8G 0 part
6. ├─centos-root 253:0 0 30G 0 lvm /
7. └─centos-swap 253:1 0 9.8G 0 lvm [SWAP]
8.sdb 8:16 0 40G 0 disk
9.└─sdb1 8:17 0 40G 0 part
10.sr0 11:0 1 1024M 0 rom
5、查看根分区的文件系统类型
命令 parted -l
6、格式化sdb1
1.[root@itcast ~]# mkfs.xfs /dev/sdb1
2.meta-data=/dev/sdb1 isize=512 agcount=4, agsize=2621376 blks
3. = sectsz=512 attr=2, projid32bit=1
4. = crc=1 finobt=0, sparse=0
5.data = bsize=4096 blocks=10485504, imaxpct=25
6. = sunit=0 swidth=0 blks
7.naming =version 2 bsize=4096 ascii-ci=0 ftype=1
8.log =internal log bsize=4096 blocks=5119, version=2
9. = sectsz=512 sunit=0 blks, lazy-count=1
10.realtime =none extsz=4096 blocks=0, rtextents=0
7、查看卷组信息（记住LV Path 和 VG Name）
8、开始扩容
1.[root@itcast ~]# pvcreate /dev/sdb1 #将sdb1分区变为pv
2.WARNING: xfs signature detected on /dev/sdb1 at offset 0. Wipe it? [y/n]: y
3. Wiping xfs signature on /dev/sdb1.
4. Physical volume "/dev/sdb1" successfully created.
5.[root@itcast ~]# vgextend centos /dev/sdb1 #将/dev/sdc1卷加入根目录所在的卷组名centos
6. Couldn't create temporary archive name. ##报错啦！
7.
执行 rm -rf /tmp/*
1.[root@itcast ~]# vgextend centos /dev/sdb1
2. Volume group "centos" successfully extended
成功了
接着查看卷组信息 （记住Free PE）
命令 vgdisplay centos
把所有空间分配给根分区
1.[root@itcast ~]# lvextend -l +10239 /dev/centos/root #10239=free pe 注意这里
2. Size of logical volume centos/root changed from 30.00 GiB (7680 extents) to
3. Logical volume centos/root successfully resized.
最后是文件系统的扩容
1.[root@itcast ~]# xfs_growfs /dev/centos/root
2.meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=1966080 blks
3. = sectsz=512 attr=2, projid32bit=1
4. = crc=1 finobt=0 spinodes=0
5.data = bsize=4096 blocks=7864320, imaxpct=25
6. = sunit=0 swidth=0 blks
7.naming =version 2 bsize=4096 ascii-ci=0 ftype=1
8.log =internal bsize=4096 blocks=3840, version=2
9. = sectsz=512 sunit=0 blks, lazy-count=1
10.realtime =none extsz=4096 blocks=0, rtextents=0
11.data blocks changed from 7864320 to 18349056
Done！
作者：小懒猫007
