Linux LVM逻辑卷分区调整
命令说明
lvextend -L 120G /dev/centos/home # 增大至120G
lvextend -L +20G /dev/centos/home # 增加20G
lvreduce -L 50G /dev/centos/home # 减小至50G
lvreduce -L -8G /dev/centos/home # 减小8G
# EXT3/4 文件系统(文件系统支持热增大和减小)
resize2fs /dev/centos/home # 执行调整
# XFS 文件系统(注意：XFS文件系统在做减小操作时需备份[被减小分区]的数据,做减小分区操作则此分区必须格式化)
xfs_growfs /dev/centos/home # 执行调整
查看信息
查看分区信息
lsblk
[root@localhost ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 298.1G 0 disk
├─sda1 8:1 0 1G 0 part /boot
└─sda2 8:2 0 297.1G 0 part
├─centos-root 253:0 0 50G 0 lvm / # 根分区
├─centos-swap 253:1 0 3.9G 0 lvm [SWAP] # swap分区
└─centos-home 253:2 0 243.2G 0 lvm /home # home分区
sdb 8:16 0 55.9G 0 disk
└─sdb1 8:17 0 55.9G 0 part /SSD
查看文件系统
df -hT
[root@localhost ~]# df -hT
文件系统 类型 容量 已用 可用 已用% 挂载点
/dev/mapper/centos-root xfs 50G 1.5G 49G 3% /
devtmpfs devtmpfs 1.8G 0 1.8G 0% /dev
tmpfs tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs tmpfs 1.9G 8.9M 1.9G 1% /run
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sdb1 xfs 56G 4.3G 52G 8% /SSD
/dev/sda1 xfs 1014M 143M 872M 15% /boot
/dev/mapper/centos-home xfs 244G 320M 243G 1% /home # 分区类型XFS
tmpfs tmpfs 371M 0 371M 0% /run/user/0
查看LV路径
lvdisplay
[root@localhost ~]# lvdisplay
--- Logical volume ---
LV Path /dev/centos/swap # Swap区路径
LV Name swap
VG Name centos
LV UUID 8YWTtu-YeqR-Gt0d-bO8L-bBeb-fb1B-nFsoQS
LV Write Access read/write
LV Creation host, time localhost.localdomain, 2018-06-14 13:18:02 +0800
LV Status available
# open 2
LV Size <3.88 GiB
Current LE 993
Segments 2
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:1
--- Logical volume ---
LV Path /dev/centos/home # home区路径
LV Name home
VG Name centos
LV UUID eUprjm-hGrH-1xO7-FBrC-AEpK-qTcY-NSeTTP
LV Write Access read/write
LV Creation host, time localhost.localdomain, 2018-06-14 13:18:02 +0800
LV Status available
# open 0
LV Size <243.21 GiB
Current LE 62261
Segments 3
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:2
--- Logical volume ---
LV Path /dev/centos/root # 根分区路径
LV Name root
VG Name centos
LV UUID YZv2zk-pf1A-XwxZ-HGDk-Xftu-TRgo-VoePMp
LV Write Access read/write
LV Creation host, time localhost.localdomain, 2018-06-14 13:18:04 +0800
LV Status available
# open 1
LV Size 50.00 GiB
Current LE 12800
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 256
Block device 253:0
free -m
[root@localhost ~]# free -m
total used free shared buff/cache available
Mem: 3709 105 3476 8 127 3409
Swap: 8067 0 8067
XFS LVM
XFS文件系统, xfs因为只能增大, 如果要减小, 只能在减小后将逻辑分区重新格式化(mkfs.xfs)才能挂载
示例：备份 home 分区数据, 减小home分区 4G 增加到Swap 分区, 格式化分区, 挂载, 恢复数据(系统：CentOS 7.5)
备份数据
mkdir -p /home/{1..100}/{1..1000} # 创建测试文件
yum -y install xfsdump # 安装备份软件
xfsdump -f /home.xfsdump /home # 将home 分区备份到 根路径下 /home.xfsdump
减小home分区空间
umount /home # 卸载分区
lvreduce -L -4G /dev/centos/home # 减小home分区4G
mkfs.xfs -f /dev/centos/home # 格式化home分区
mount /home # 挂载分区
增加Swap分区空间
swapoff /dev/centos/swap # 关闭swap分区
lvextend -l +100%FREE /dev/centos/swap # 将剩余所有空间添加到swap分区
mkswap /dev/centos/swap # 格式化分区
swapon /dev/centos/swap # 启用swap分区
恢复home数据
xfsrestore -f /home.xfsdump /home
查看结果
为了确认分区正常请重启系统
lsblk
[root@localhost ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 298.1G 0 disk
├─sda1 8:1 0 1G 0 part /boot
└─sda2 8:2 0 297.1G 0 part
├─centos-root 253:0 0 50G 0 lvm /
├─centos-swap 253:1 0 7.9G 0 lvm [SWAP]
└─centos-home 253:2 0 239.2G 0 lvm /home
sdb 8:16 0 55.9G 0 disk
└─sdb1 8:17 0 55.9G 0 part /SSD
减小Swap分区增加根分区
此处不用备份信息(减小分区为swap)
swapoff /dev/centos/swap # 关闭swap分区
lvreduce -L -4G /dev/centos/swap # 减小swap分区4G
mkswap /dev/centos/swap # 格式化swap分区4G
swapon /dev/centos/swap # 启用swap分区
lvextend -l +100%FREE /dev/centos/root # 将剩余所有空间添加到根分区
xfs_growfs /dev/centos/root # 应用扩容
# 查看信息
lsblk
[root@localhost ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 298.1G 0 disk
├─sda1 8:1 0 1G 0 part /boot
└─sda2 8:2 0 297.1G 0 part
├─centos-root 253:0 0 54G 0 lvm /
├─centos-swap 253:1 0 3.9G 0 lvm [SWAP]
└─centos-home 253:2 0 239.2G 0 lvm /home
sdb 8:16 0 55.9G 0 disk
└─sdb1 8:17 0 55.9G 0 part /SSD