0x01 新增加一块磁盘到SWAP空间
# 格式化新增硬盘
fdisk /dev/sdc
n
p
t
8e
w
# 关闭系统交换区
swapoff /dev/centos/swap
# 添加 sdc1 到 VG
vgextend centos /dev/sdc1
# 扩展 VG 剩余空间到 lv
lvextend -l 100%VG /dev/centos/swap
# 设置交换分区文件
mkswap /dev/centos/swap
# 激活交换分区
swapon /dev/centos/swap
# 查询交换分区信息
dfree -h
0x02 扩容现有硬盘空间并划分到SWAP
# 格式化新增硬盘空间
fdisk /dev/sda
n
p
t
8e
w
reboot now
# 关闭系统交换区
swapoff /dev/centos/swap
# 扩展SWAP VG
vgextend centos /dev/$(lsblk | grep sda | tail -1 | awk -F'[─| ]' '{print $2}')
# 扩展SWAP LV
lvextend -l 100%VG /dev/centos/swap
# 建立交换分区
mkswap /dev/centos/swap
# 激活系统交换区
swapon /dev/centos/swap
0x03 特殊情况
系统自身具备扩展过一次SWAP，现进行第二次扩展，且需要同步扩展「/」目录
3.1 查询可用块设备的信息及现有SWAP信息
[root@localhost ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
fd0 2:0 1 4K 0 disk
sda 8:0 0 70G 0 disk
sda1 8:1 0 1G 0 part /boot
sda2 8:2 0 15G 0 part
centos-root 253:0 0 13.4G 0 lvm /
centos-swap 253:1 0 9.6G 0 lvm [SWAP]
sda3 8:3 0 8G 0 part
centos-swap 253:1 0 9.6G 0 lvm [SWAP]
sdb 8:16 0 150G 0 disk
sr0 11:0 1 1024M 0 rom
[root@localhost ~]# free -h
total used free shared buff/cache available
Mem: 15G 245M 15G 12M 198M 14G
Swap: 9.6G 0B 9.6G
3.2 删除 sda3 分区信息
# 关闭系统交换区
[root@localhost ~]# swapoff /dev/centos/swap
# 减小 lv 逻辑卷的大小，缩减到可以踢出 sda3 的空间
[root@localhost ~]# lvreduce -L -8G /dev/centos/swap
WARNING: Reducing active logical volume to <1.60 GiB.
THIS MAY DESTROY YOUR DATA (filesystem etc.)
Do you really want to reduce centos/swap? [y/n]: y
Size of logical volume centos/swap changed from <9.60 GiB (2457 extents) to <1.60 GiB (409 extents).
Logical volume centos/swap successfully resized.
# 从 VG 中删除 sda3
[root@localhost ~]# vgreduce centos /dev/sda3
Removed "/dev/sda3" from volume group "centos"
# 从 pv 中删除 sda3
[root@localhost ~]# pvremove /dev/sda3
Labels on physical volume "/dev/sda3" successfully wiped.
# 删除 sda3 分区
[root@localhost ~]# fdisk /dev/sda
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/sda: 75.2 GB, 75161927680 bytes, 146800640 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: 0x000bb4bd
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 2099199 1048576 83 Linux
/dev/sda2 2099200 33554431 15727616 8e Linux LVM
/dev/sda3 33554432 50331647 8388608 8e Linux LVM
Command (m for help): d
Partition number (1-3, default 3): 3
Partition 3 is deleted
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
# 重启服务器
[root@localhost ~]# rebot ot now
3.3 创建新分区
[root@localhost ~]# fdisk /dev/sda
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): n
Partition type:
p primary (2 primary, 0 extended, 2 free)
e extended
Select (default p): p
Partition number (3,4, default 3): 3
First sector (33554432-146800639, default 33554432):
Using default value 33554432
Last sector, +sectors or +size{K,M,G} (33554432-146800639, default 146800639):
Using default value 146800639
Partition 3 of type Linux and of size 54 GiB is set
Command (m for help): t
Partition number (1-3, default 3):
Hex code (type L to list all codes): 8e
Changed type of partition 'Linux' to 'Linux LVM'
Command (m for help): p
Disk /dev/sda: 75.2 GB, 75161927680 bytes, 146800640 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: 0x000bb4bd
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 2099199 1048576 83 Linux
/dev/sda2 2099200 33554431 15727616 8e Linux LVM
/dev/sda3 33554432 146800639 56623104 8e Linux LVM
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
[root@localhost ~]# reboot now
3.4 扩展SWAP分区到16G
# 添加 sda3 到 VG
[root@localhost ~]# vgextend centos /dev/sda3
Physical volume "/dev/sda3" successfully created.
Volume group "centos" successfully extended
# 扩展 lv 空间15.4G
[root@localhost ~]# lvextend -L +15.4G /dev/centos/swap
Rounding size to boundary between physical extents: 15.40 GiB.
Size of logical volume centos/swap changed from <1.60 GiB (409 extents) to 17.00 GiB (4352 extents).
Logical volume centos/swap successfully resized.
# 设置交换分区文件
[root@localhost ~]# mkswap /dev/centos/swap
mkswap: /dev/centos/swap: warning: wiping old swap signature.
Setting up swapspace version 1, size = 17825788 KiB
no label, UUID=7158b624-ecb8-4bfb-b019-f562b55ab5de
# 激活交换分区
[root@localhost ~]# swapon /dev/centos/swap
# 查询交换分区信息
[root@localhost ~]# dfree -h
total used free shared buff/cache available
Mem: 15G 248M 15G 11M 198M 14G
Swap: 16G 0B 16G
3.5 扩展剩余空间到「/」
# 扩展 VG 剩余空间到 lv
[root@localhost ~]# lvextend -l 100%VG /dev/centos/root
Size of logical volume centos/root changed from 13.39 GiB (3429 extents) to 51.99 GiB (13310 extents).
Logical volume centos/root successfully resized.
# 刷新空间
[root@localhost ~]# xfs_growfs /dev/centos/root
meta-data=/dev/mapper/centos-root isize=512 agcount=4, agsize=877824 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=3511296, 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 3511296 to 13629440
# 查询结果
[root@localhost ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
fd0 2:0 1 4K 0 disk
sda 8:0 0 70G 0 disk
sda1 8:1 0 1G 0 part /boot
sda2 8:2 0 15G 0 part
centos-root 253:0 0 52G 0 lvm /
centos-swap 253:1 0 17G 0 lvm [SWAP]
sda3 8:3 0 54G 0 part
centos-root 253:0 0 52G 0 lvm /
centos-swap 253:1 0 17G 0 lvm [SWAP]
sdb 8:16 0 150G 0 disk
sr0 11:0 1 1024M 0 rom
[root@localhost ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 52G 5.9G 47G 12% /
devtmpfs 7.8G 0 7.8G 0% /dev
tmpfs 7.8G 0 7.8G 0% /dev/shm
tmpfs 7.8G 12M 7.8G 1% /run
tmpfs 7.8G 0 7.8G 0% /sys/fs/cgroup
/dev/sda1 1014M 145M 870M 15% /boot
tmpfs 1.6G 0 1.6G 0% /run/user/0
文档信息
- 本文作者：Minggle
- 本文链接：https://mingsec.com/2021/08/03/CentOS-SWAP-add/
- 版权声明：自由转载-非商用-非衍生-保持署名（创意共享3.0许可证）