linux服務器如何調整分區大小無損的方法

我們做服務器搭建維護的時候都會因為各種需求而需要調整分區大小。為了效率我們肯定要做到無損的調整，而可能很多不是很熟練的人不知道怎麼調，下面小編就為大家分享下linux服務器無損調整分區大小的'方法吧。

情況：

home：500G

root：50G

root分區不夠用

思路：把home分區的空間劃一部分到root分區

# 設置home分區大小為200G，釋放300G空間

$ lvreduce -L 200G /dev/centos/home

# 將空閒空間擴展到root分區

$ lvextend -l +100%FREE /dev/centos/root

# 使用XFS文件系統自帶的命令集增加分區空間

$ xfs_growfs /dev/mapper/centos-root

實例

situation

掛載在根目錄的分區 /dev/mapper/centos-root 爆滿，佔用100%

$ df -h

Filesystem Size Used Avail Use% Mounted on

/dev/mapper/centos-root 50G 50G 19M 100% /

devtmpfs 32G 0 32G 0% /dev

tmpfs 32G 0 32G 0% /dev/shm

tmpfs 32G 2.5G 29G 8% /run

tmpfs 32G 0 32G 0% /sys/fs/cgroup

/dev/mapper/centos-home 476G 33M 476G 1% /home

/dev/sda1 497M 238M 259M 48% /boot

tmpfs 6.3G 0 6.3G 0% /run/user/0

analyze

掛載在根目錄的分區空間太小，只有50G，而服務器 home 目錄為非常用目錄，掛在了近500G的空間。

思路：從 centos-home 分區劃出300G空間到 centos-root 分區。

operation

1.查看各分區信息

$ lvdisplay

--- Logical volume ---

LV Path /dev/centos/home

LV Name home

VG Name centos

LV UUID 1fAt1E-bQsa-1HXR-MCE2-5VZ1-xzBz-iI1SLv

LV Write Access read/write

LV Creation host, time localhost, 2016-10-26 17:23:47 +0800

LV Status available

# open 0

LV Size 475.70 GiB

Current LE 121778

Segments 1

Allocation inherit

Read ahead sectors auto

- currently set to 256

Block device 253:2

--- Logical volume ---

LV Path /dev/centos/root

LV Name root

VG Name centos

LV UUID lD64zY-yc3Z-SZaB-dAjK-03YM-2gM8-pfj4oo

LV Write Access read/write

LV Creation host, time localhost, 2016-10-26 17:23:48 +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

2.減少/home分區空間

# 釋放 /dev/centos/home 分區 300G 的空間

# 命令設置 /dev/centos/home 分區 200G空間

$ lvreduce -L 200G /dev/centos/home

WARNING: Reducing active logical volume to 200.00 GiB.

THIS MAY DESTROY YOUR DATA (filesystem etc.)

Do you really want to reduce centos/home? [y/n]: y

Size of logical volume centos/home changed from 475.70 GiB (121778 extents) to 200.00 GiB (51200 extents).

Logical volume centos/home successfully resized.

3.增加/root分區空間

$ lvextend -l +100%FREE /dev/centos/root

Size of logical volume centos/root changed from 50.06 GiB (12816 extents) to 325.76 GiB (83394 extents).

Logical volume centos/root successfully resized.

4.擴展XFS文件空間大小

$ xfs_growfs /dev/mapper/centos-root

meta-data=/dev/mapper/centos-root isize=256 agcount=4, agsize=3276800 blks

= sectsz=512 attr=2, projid32bit=1

= crc=0 finobt=0 spinodes=0

data = bsize=4096 blocks=13107200, imaxpct=25

= sunit=0 swidth=0 blks

naming =version 2 bsize=4096 ascii-ci=0 ftype=0

log =internal bsize=4096 blocks=6400, version=2

= sectsz=512 sunit=0 blks, lazy-count=1

realtime =none extsz=4096 blocks=0, rtextents=0

data blocks changed from 13107200 to 85395456