centos 6/7 vm 通过lvm扩展磁盘/root

1 查看centos设备信息

[root@localhost ~]# lsblk
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0   50G  0 disk 
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0   49G  0 part 
  ├─centos-root 253:0    0 65.1G  0 lvm  /
  └─centos-swap 253:1    0  3.9G  0 lvm  [SWAP]
sdb               8:16   0   20G  0 disk 
└─sdb1            8:17   0   20G  0 part 
  └─centos-root 253:0    0 65.1G  0 lvm  /
sr0              11:0    1  4.2G  0 rom 
NAME : 这是块设备名。
MAJ:MIN : 显示主要和次要设备号。
RM : 显示设备是否可移动设备。sr0的RM值等于1,这说明他们是可移动设备。
SIZE : 列出设备的容量大小信息。例如50G表明该设备大小为50G,而1K表明该设备大小为1KB。
RO : 该项表明设备是否为只读。在本案例中,所有设备的RO值为0,表明他们不是只读的。
TYPE :显示块设备是否是磁盘或磁盘上的一个分区。在本例中,sda和sdb是磁盘,而sr0是只读存储(rom)。
MOUNTPOINT : 指出设备挂载的挂载点。

2 虚拟机,扩展根目录,使用lvm

[root@localhost ~]# df -h
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/centos-root   46G  3.1G   43G   7% /
devtmpfs                 1.9G     0  1.9G   0% /dev
tmpfs                    1.9G     0  1.9G   0% /dev/shm
tmpfs                    1.9G  9.0M  1.9G   1% /run
tmpfs                    1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/sda1               1014M  178M  837M  18% /boot
tmpfs                    380M  8.0K  380M   1% /run/user/42
tmpfs                    380M     0  380M   0% /run/user/1000
[root@localhost ~]# lsblk
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0   50G  0 disk 
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0   49G  0 part 
  ├─centos-root 253:0    0 45.1G  0 lvm  /
  └─centos-swap 253:1    0  3.9G  0 lvm  [SWAP]
sr0              11:0    1 1024M  0 rom

1 添加多块磁盘(vm上添加2块50g磁盘),扩展根目录

[root@zabbix ~]# df -h
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/centos-root   46G   12G   34G  27% /
devtmpfs                 1.9G     0  1.9G   0% /dev
tmpfs                    1.9G     0  1.9G   0% /dev/shm
tmpfs                    1.9G  9.1M  1.9G   1% /run
tmpfs                    1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/sda1               1014M  178M  837M  18% /boot
tmpfs                    380M  8.0K  380M   1% /run/user/42
tmpfs                    380M     0  380M   0% /run/user/0
tmpfs                    380M     0  380M   0% /run/user/1000
##lsblk查看新插入硬盘情况,如果未显示新添加的磁盘,需用 echo "- - -" > /sys/class/scsi_host/host0/scan,此命令进行激活,激活后即可查看到新加的磁盘。
[root@zabbix ~]# lsblk
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0   50G  0 disk 
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0   49G  0 part 
  ├─centos-root 253:0    0 45.1G  0 lvm  /
  └─centos-swap 253:1    0  3.9G  0 lvm  [SWAP]
sdb               8:16   0   50G  0 disk 
sdc               8:32   0   50G  0 disk 
sr0              11:0    1  4.2G  0 rom 
[root@zabbix ~]# ll /dev/sdb /dev/sdc 
brw-rw---- 1 root disk 8, 16 Sep 11 09:00 /dev/sdb
brw-rw---- 1 root disk 8, 32 Sep 11 09:00 /dev/sdc
[root@zabbix ~]# fdisk /dev/sdb ##选择新增硬盘
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.

Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xb0001f51.

Command (m for help): p ##查看已分区数量

Disk /dev/sdb: 53.7 GB, 53687091200 bytes, 104857600 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: 0xb0001f51

   Device Boot      Start         End      Blocks   Id  System

Command (m for help): n ##新增加一个分区
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p ##分区类型选择为主分区
Partition number (1-4, default 1): 1 ##分区号选1,由于扩容盘所以只只设置一个分区
First sector (2048-104857599, default 2048): ##回车
Using default value 2048 
Last sector, +sectors or +size{K,M,G} (2048-104857599, default 104857599): #默认 回车
Using default value 104857599
Partition 1 of type Linux and of size 50 GiB is set

Command (m for help): p

Disk /dev/sdb: 53.7 GB, 53687091200 bytes, 104857600 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: 0xb0001f51 ##增加分区,会发现多了一个分区

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048   104857599    52427776   83  Linux

Command (m for help): t
Selected partition 1
Hex code (type L to list all codes): 1

WARNING: If you have created or modified any DOS 6.xpartitions, please see the fdisk manual page for additionalinformation.

Changed type of partition 'Linux' to 'FAT12'

Command (m for help): t ##
Selected partition 1
Hex code (type L to list all codes): 8e ##修改分区类型,把linux修改为'Linux LVM'

WARNING: If you have created or modified any DOS 6.xpartitions, please see the fdisk manual page for additionalinformation.

Changed type of partition 'FAT12' to 'Linux LVM'

Command (m for help): p ##再次查看分区情况确认是否修改成功

Disk /dev/sdb: 53.7 GB, 53687091200 bytes, 104857600 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: 0xb0001f51

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048   104857599    52427776   8e  Linux LVM ##此次修改成功

Command (m for help): w ##最后写入分区表,保存并退出即可
The partition table has been altered!

Calling ioctl() to re-read partition table.
Syncing disks.
View Code
[root@zabbix ~]# lsblk
NAME            MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
sda               8:0    0   50G  0 disk 
├─sda1            8:1    0    1G  0 part /boot
└─sda2            8:2    0   49G  0 part 
  ├─centos-root 253:0    0 45.1G  0 lvm  /
  └─centos-swap 253:1    0  3.9G  0 lvm  [SWAP]
sdb               8:16   0   50G  0 disk 
└─sdb1            8:17   0   50G  0 part 
sdc               8:32   0   50G  0 disk 
└─sdc1            8:33   0   50G  0 part 
sr0              11:0    1  4.2G  0 rom  
[root@zabbix ~]# lvm  ##进入lvm管理
lvm> pvcreate /dev/sdb1 /dev/sdc1 ##初始化刚才的2个分区
  Physical volume "/dev/sdb1" successfully created.
  Physical volume "/dev/sdc1" successfully created.
lvm> vgdisplay ##查看vg的可用空间
  --- Volume group ---
  VG Name               centos
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               2
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               <49.00 GiB
  PE Size               4.00 MiB
  Total PE              12543
  Alloc PE / Size       12542 / 48.99 GiB
  Free  PE / Size       1 / 4.00 MiB
  VG UUID               wGqWZa-pMkw-NxWJ-2fTQ-rEvZ-329h-bKIRu2
   
lvm> vgextend centos /dev/sdb1 /dev/sdc1 ##将初始化过的分区加入到虚拟卷组名
  Volume group "centos" successfully extended
lvm> lvextend -L +99G /dev/mapper/centos-root  ##扩展已有的容量
  Size of logical volume centos/root changed from <45.12 GiB (11550 extents) to <144.12 GiB (36894 extents).
  Logical volume centos/root successfully resized.
lvm> pvdisplay ##查看卷容量
  --- Physical volume ---
  PV Name               /dev/sda2
  VG Name               centos
  PV Size               <49.00 GiB / not usable 3.00 MiB
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              12543
  Free PE               0
  Allocated PE          12543
  PV UUID               7AVqYT-3yaz-dL7c-tSgq-hJpZ-csmI-YcXBig
   
  --- Physical volume ---
  PV Name               /dev/sdb1
  VG Name               centos
  PV Size               <50.00 GiB / not usable 3.00 MiB
  Allocatable           yes (but full)
  PE Size               4.00 MiB
  Total PE              12799
  Free PE               0
  Allocated PE          12799
  PV UUID               G1R8eV-DvER-Jz1x-1hpk-mOzv-ZdJ7-PZnNim
   
  --- Physical volume ---
  PV Name               /dev/sdc1
  VG Name               centos
  PV Size               <50.00 GiB / not usable 3.00 MiB
  Allocatable           yes 
  PE Size               4.00 MiB
  Total PE              12799
  Free PE               255
  Allocated PE          12544
  PV UUID               wtA8My-5caU-OWUu-2OQO-heuQ-0g8I-RHPLwZ
   
lvm> quit ##退出
  Exiting.

##centos6.10

mkfs.ext4 /dev/sdh1
[root@rac02 ~]# cat /etc/fstab |grep VolGroup-lv_home
/dev/mapper/VolGroup-lv_home /home                   ext4    defaults        1 2
### resize2fs /dev/mapper/VolGroup-lv_home
[root@zabbix ~]# cat /etc/fstab |grep centos-root ##查看文件系统格式,如果是xfs,需要用xfs的命令来扩展磁盘
/dev/mapper/centos-root /                       xfs     defaults        0 0
[root@zabbix ~]# xfs_growfs /dev/mapper/centos-root 
meta-data=/dev/mapper/centos-root isize=512    agcount=4, agsize=2956800 blks
         =                       sectsz=512   attr=2, projid32bit=1
         =                       crc=1        finobt=0 spinodes=0
data     =                       bsize=4096   blocks=11827200, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
log      =internal               bsize=4096   blocks=5775, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 11827200 to 37779456
[root@zabbix ~]# df -h ##根目录扩展成功
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/centos-root  145G   12G  133G   9% /
devtmpfs                 1.9G     0  1.9G   0% /dev
tmpfs                    1.9G     0  1.9G   0% /dev/shm
tmpfs                    1.9G  9.1M  1.9G   1% /run
tmpfs                    1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/sda1               1014M  178M  837M  18% /boot
tmpfs                    380M   12K  380M   1% /run/user/42
tmpfs                    380M     0  380M   0% /run/user/0
tmpfs                    380M     0  380M   0% /run/user/1000
[root@zabbix ~]# lsblk
NAME            MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda               8:0    0    50G  0 disk 
├─sda1            8:1    0     1G  0 part /boot
└─sda2            8:2    0    49G  0 part 
  ├─centos-root 253:0    0 144.1G  0 lvm  /
  └─centos-swap 253:1    0   3.9G  0 lvm  [SWAP]
sdb               8:16   0    50G  0 disk 
└─sdb1            8:17   0    50G  0 part 
  └─centos-root 253:0    0 144.1G  0 lvm  /
sdc               8:32   0    50G  0 disk 
└─sdc1            8:33   0    50G  0 part 
  └─centos-root 253:0    0 144.1G  0 lvm  /
sr0              11:0    1   4.2G  0 rom  
[root@zabbix ~]# vgs
  VG     #PV #LV #SN Attr   VSize    VFree   
  centos   3   2   0 wz--n- <148.99g 1020.00m
[root@zabbix ~]# lvs
  LV   VG     Attr       LSize    Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root centos -wi-ao---- <144.12g                                                    
  swap centos -wi-ao----   <3.88g    
[root@localhost ~]# fdisk -l
[root@localhost ~]# vgdisplay -v centos
原文地址:https://www.cnblogs.com/yhq1314/p/12331428.html