Docker镜像、容器等文件目录默认在系统盘，虚拟机分配的系统盘20G容量也太小，研究下系统盘扩容
linux 系统分区 /dev/sda3，创建新系统分区sda4，扩容20G
基本的逻辑卷管理概念
基本的逻辑卷管理概念：
PV（Physical Volume）- 物理卷
物理卷在逻辑卷管理中处于最底层，它可以是实际物理硬盘上的分区，也可以是整个物理硬盘，也可以是raid设备。
VG（Volumne Group）- 卷组
卷组建立在物理卷之上，一个卷组中至少要包括一个物理卷，在卷组建立之后可动态添加物理卷到卷组中。一个逻辑卷管理系统工程中可以只有一个卷组，也可以拥有多个卷组。
LV（Logical Volume）- 逻辑卷
逻辑卷建立在卷组之上，卷组中的未分配空间可以用于建立新的逻辑卷，逻辑卷建立后可以动态地扩展和缩小空间。系统中的多个逻辑卷可以属于同一个卷组，也可以属于不同的多个卷组。
在虚拟机分配20G硬盘
略
系统加盘sda4
[root@node1 ~]# 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 (3 primary, 0 extended, 1 free)
e extended
Select (default e): p
Selected partition 4
First sector (20971520-62914559, default 20971520):
Using default value 20971520
Last sector, +sectors or +size{K,M,G} (20971520-62914559, default 62914559):
Using default value 62914559
Partition 4 of type Linux and of size 20 GiB is set
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.
加入sda4
[root@node1 ~]# lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 30G 0 disk
├─sda1 8:1 0 300M 0 part /boot
├─sda2 8:2 0 1G 0 part
├─sda3 8:3 0 8.7G 0 part /
└─sda4 8:4 0 20G 0 part
sr0 11:0 1 1024M 0 rom
创建物理卷
[root@node1 ~]# pvcreate /dev/sda4
Physical volume "/dev/sda4" successfully created.
查看物理卷
[root@node1 ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda4 lvm2 --- 20.00g 20.00g
[root@node1 ~]# pvdisplay
"/dev/sda4" is a new physical volume of "20.00 GiB"
--- NEW Physical volume ---
PV Name /dev/sda4
VG Name
PV Size 20.00 GiB
Allocatable NO
PE Size 0
Total PE 0
Free PE 0
Allocated PE 0
PV UUID dnbfor-Mftv-L8o5-gdbP-sVdj-H6HY-tHW4J8
[root@node1 ~]# partprobe
创建卷组
[root@node1 ~]# vgcreate vg0 /dev/sda4
Volume group "vg0" successfully created
#查看卷组
[root@node1 ~]# vgscan
Reading volume groups from cache.
Found volume group "vg0" using metadata type lvm2
[root@node1 ~]# vgextend vg0 /dev/sda6 #增加一个卷组
[root@node1 ~]# pvmove /dev/sda6 //移走PV的数据
[root@node1 ~]# vgreduce vg0 /dev/sda6 //从vg0中删除物理卷
创建逻辑卷（单位:M）
[root@node1 ~]# lvcreate -L 10G -n lv1 vg0
Logical volume "lv1" created.
[root@node1 /]# lvscan
ACTIVE '/dev/vg0/lv1' [10.00 GiB] inherit
[root@node1 ~]# lvdisplay
--- Logical volume ---
LV Path /dev/vg0/lv1
LV Name lv1
VG Name vg0
LV UUID o9Qy20-I08o-GtAK-v0y9-DuY5-QlYl-J63IWc
LV Write Access read/write
LV Creation host, time node1, 2021-03-28 21:40:00 +0800
LV Status available
# open 0
LV Size 10.00 GiB
Current LE 2560
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
建文件系统（格式化）
[root@node1 ~]# mkfs -t xfs /dev/vg0/lv1
meta-data=/dev/vg0/lv1 isize=512 agcount=4, agsize=655360 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0, sparse=0
data = bsize=4096 blocks=2621440, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=1
log =internal log bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
挂载逻辑卷
[root@node1 ~]# mount /dev/vg0/lv1 /home
[root@node1 ~]# df -h #扩容前10G
Filesystem Size Used Avail Use% Mounted on
/dev/sda3 8.7G 3.3G 5.5G 38% /
/dev/sda1 297M 118M 180M 40% /boot
/dev/mapper/vg0-lv1 10G 33M 10G 1% /home
tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
--------------------------------------------------------------------------------
为根分区扩展空间
[root@node1 ~]# lvextend -L +1G /dev/mapper/vg0-lv1
[root@node1 ~]# resize2fs -f /dev/mapper/vg0-lv1 #不生效使用下面
--------------------------------------------------------------------------------
[root@node1 ~]# xfs_growfs /dev/mapper/vg0-lv1
meta-data=/dev/mapper/vg0-lv1 isize=512 agcount=4, agsize=655360 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=0 spinodes=0
data = bsize=4096 blocks=2621440, 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 2621440 to 4507648
--------------------------------------------------------------------------------
[root@node1 ~]# df -h #扩容后18G
Filesystem Size Used Avail Use% Mounted on
/dev/sda3 8.7G 3.3G 5.5G 38% /
devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 297M 118M 180M 40% /boot
/dev/mapper/vg0-lv1 18G 33M 18G 1% /home
完
修改docker默认目录（终极大招）
修改docker默认目录到/home/docker下
Docker镜像、容器等文件目录迁移
/halikes23/article/details/87269997
[root@node1 ~]# systemctl stop docker
[root@node1 ~]# mkdir /home/docker
[root@node1 ~]# cp -R /var/lib/docker/* /home/docker/
[root@node1 ~]# cat /etc/docker/
{
"registry-mirrors": [""],
"exec-opts": ["=systemd"],
"graph": "/home/docker" #添加新目录
}
[root@node1 ~]# systemctl daemon-reload && systemctl start docker
[root@node1 ~]# ln -s /usr/libexec/docker/docker-runc-current docker-runc
删除原有文件
[root@node1 ~]# rm -rf /var/lib/docker
虽然没有用删除操作，但是看到/var/lib/docker目录已经不存在了，镜像与容器显示在了新的目录/home/docker中
[root@node1 ~]# df -Th
Filesystem Type Size Used Avail Use% Mounted on
/dev/sda3 xfs 8.7G 2.7G 6.1G 31% /
devtmpfs devtmpfs 1.4G 0 1.4G 0% /dev
tmpfs tmpfs 1.4G 0 1.4G 0% /dev/shm
tmpfs tmpfs 1.4G 9.3M 1.4G 1% /run
tmpfs tmpfs 1.4G 0 1.4G 0% /sys/fs/cgroup
/dev/sda1 xfs 297M 118M 180M 40% /boot
/dev/mapper/vg0-lv1 xfs 20G 831M 20G 5% /home
tmpfs tmpfs 1.4G 12K 1.4G 1% /var/lib/kubelet/pods/9bb01287-42bd-4d81-9e24-4fd1b2953df1/volumes/~secret/default-token-2l58c
tmpfs tmpfs 1.4G 12K 1.4G 1% /var/lib/kubelet/pods/dcbaf00d-64f2-4c41-8d94-78e919a84db3/volumes/~secret/flannel-token-k794f
tmpfs tmpfs 1.4G 12K 1.4G 1% /var/lib/kubelet/pods/9e616d2b-6328-4edf-bf03-8666fb094871/volumes/~secret/kube-proxy-token-78wp7
tmpfs tmpfs 284M 0 284M 0% /run/user/0
overlay overlay 20G 831M 20G 5% /home/docker/overlay2/136ee7e8387889f29b5d8b348d6efbad849d8c961fa65eb3d0777a002daac01b/merged
overlay overlay 20G 831M 20G 5% /home/docker/overlay2/0ae46f788b0344c898b2b05c00ad644e5abc2d5629048b76393bf53e93bc5173/merged
overlay overlay 20G 831M 20G 5% /home/docker/overlay2/c9fdd6a853ebb74d6aa5d6a7116b57ba4152c9ae6fcd50c1e5c75198961a49ba/merged
shm tmpfs 64M 0 64M 0% /home/docker/containers/3f778588c1026b13831ca20b83ebb2049660ed2d275ad869cace012b1322bea8/mounts/shm
shm tmpfs 64M 0 64M 0% /home/docker/containers/334ed06000ed551253d46f7fb93fe96ff3fbd7a1beddc9f6dbbf83228dce6b1b/mounts/shm
shm tmpfs 64M 0 64M 0% /home/docker/containers/b8644ce2df31395ca9d985cf1c27ed000ee0aff164d0b9bad33738d261e47094/mounts/shm
overlay overlay 20G 831M 20G 5% /home/docker/overlay2/a4723f525ef18097008ca12f6dad08c40a93a240c4fbf3c278333a70ca14634f/merged
overlay overlay 20G 831M 20G 5% /home/docker/overlay2/4fa16c90c3201c2766dd99b2aa0153f9d7827e57869e1d07b307ab24afa0e7c3/merged
overlay overlay 20G 831M 20G 5% /home/docker/overlay2/746c68cd3386c7f246439bc7cfb1a1f13171b83b8596d6e907c7147bcf88d159/merged
参考资料
Linux虚拟机 sda分区扩容
/liuweijin_hot/article/details/105082645
centos7 -lvm卷组
/
逻辑卷的使用
https://blog./9480860/1700288
linux如何使用umount命令强制卸载文件系统
/qq_19175749/article/details/51154529
Docker镜像、容器等文件目录迁移
/halikes23/article/details/87269997