lvm creates logical volumes

创建物理卷
pvcreat /dev/sd{b,c}    //建立物理卷
创建物理卷组
vgcreate vg1 /devsdb /dev/sdc      //创建物理卷组vg1
创建逻辑卷
lvcreate -L 10G -n ggg vg1  //在vg0卷组上创建名为ggg,大小为10G的逻辑卷
                        （-L指定创建的LV大小,-l指定创建的LV的PE数量,-n是LV的名字）

The logical volume was created successfully but cannot be used yet,需要建立文件系统

建立文件系统

mkfs.xfs /dev/vg1/ggg    //建立文件系统

挂载

mount /dev/vg1/ggg /mnt //It can be used after the installation is successful

创建步骤

 1.建立物理卷

[[email protected] ~]# pvcreate /dev/sd{b,c}
                         //     命令         设备名（物理卷名）

2.建立卷组

3. 建立逻辑卷

 [[email protected] ~]# lvcreate             -L    23G                   -n     ky22                    vg1

                    //创建逻辑卷命令     指定逻辑卷大小          创建逻辑卷名            Which volume group to take frompe

4.建立文件系统

mkfs.xfs                       /dev/vg1/ky22

  //建立文件系统          vg1The name of the volume group obtained by yourself     ky22 The name of the logical volume taken by yourself

 5.挂载

mount    /dev/vg1/ky22     /mnt

It can be used after the mount is successful

如何扩容：

xfsExpansion in the system：
情况一：vgenough to expand lvextend  -L  +3G    /dev/vg1/ky22

 xfs_growfs /dev/vg1/ky22

情况二：vgNot stretched enough,You have to expand the equipment first and then expand the system

Expand equipment： pvcreate /dev/vdd  //创建物理卷/dev/vdd

vgextend vg1 /dev/vdd ##Insert the new physical volumevddAdd to an existing volume groupvg1

扩展逻辑卷

lvextend  -L  +3G    /dev/vg1/ky22

xfs_growfs /dev/vg1/ky22

ext4System expansion

[[email protected] ~]# umount /mnt ##先卸载
[[email protected] ~]# mkfs.ext4 /dev/vg0/lv0 ##格式化逻辑卷 ,And change the system toext4
[[email protected] ~]# mount /dev/vg0/lv0 /mnt/ ##挂载
[[email protected] ~]# lvextend -L 1800M /dev/vg0/lv0 ##Increase logical volume space
Extending logical volume lv0 to 1.76 GiB Logical volume lv0 successfully resized
[[email protected] ~]# resize2fs /dev/vg0/lv0 ##更新逻辑卷信息

缩减逻辑卷空间

[[email protected] ~]# umount /mnt ##先卸载
[[email protected] ~]# e2fsck -f /dev/vg0/lv0 ##Scan for free space on logical volumes
[[email protected] ~]# resize2fs /dev/vg0/lv0 1000M ##Device files are reduced to 1000M
[[email protected] ~]# lvreduce -L 1000M /dev/vg0/lv0 ##将逻辑卷减少到1000M
[[email protected] ~]# mount /dev/vg0/lv0 /mnt ##挂载

缩减vg：（Migrate to an idle device）

[[email protected] ~]# pvmove /dev/vdb1 /dev/vdb2 ##将vdb1The spatial data is transferred tovdb2
/dev/vdb1: Moved: 88.0%
/dev/vdb1: Moved: 100.0% ##Data transfer succeeded
[[email protected] ~]# vgreduce vg0 /dev/vdb1 ##将/dev/vdb1分区从vg0卷组中移除
Removed "/dev/vdb1" from volume group "vg0"
[[email protected] ~]# pvremove /dev/vdb1 ##把/dev/vdb1The partition is removed from the system
Labels on physical volume "/dev/vdb1" successfully wiped

注意：将vdb1The spatial data is transferred tovdb2时,要确保vdb2enough space to be able tovdb1的数据转移,Otherwise, it needs to be set firstvdb1缩减.

磁盘配额

[[email protected] ~]# xfs_quota -x -c 'limit -u bsoft=20M bhard=30M isoft=5 ihard=6 zhangsan' /opt/log/ 
[[email protected] ~]# chmod 777 /opt/log/
[[email protected] ~]# su zhangsan
[[email protected] log]$ touch file{1..10}.txt
touch: 无法创建"file7.txt": 超出磁盘限额
touch: 无法创建"file8.txt": 超出磁盘限额
touch: 无法创建"file9.txt": 超出磁盘限额
touch: 无法创建"file10.txt": 超出磁盘限额
[[email protected] log]$ ls
file1.txt file2.txt file3.txt file4.txt file5.txt file6.txt
[[email protected] log]$ dd if=/dev/zero of=/opt/log/test.txt bs=1M count=20
记录了20+0 的读入
记录了20+0 的写出
[[email protected] log]$ dd if=/dev/zero of=/opt/log/test1.txt bs=1M count=20
dd: 写入"/opt/log/test1.txt" 出错: 超出磁盘限额
记录了11+0 的读入
记录了10+0 的写出
10485760字节(10 MB)已复制,0.00546079 秒,1.9 GB/秒
[[email protected] log]$ touch file{1..10}.txt
touch: 无法创建"file1.txt": 超出磁盘限额
touch: 无法创建"file2.txt": 超出磁盘限额
touch: 无法创建"file3.txt": 超出磁盘限额
touch: 无法创建"file10.txt": 超出磁盘限额
[[email protected] log]$ ls
test1.txt test.txt
[[email protected] log]$ rm -rf *
[[email protected] log]$ touch file{1..10}.txt
touch: 无法创建"file7.txt": 超出磁盘限额
touch: 无法创建"file8.txt": 超出磁盘限额
touch: 无法创建"file9.txt": 超出磁盘限额
touch: 无法创建"file10.txt": 超出磁盘限额
[[email protected] log]$ ls
file1.txt file2.txt file3.txt file4.txt file5.txt file6.txt