LVM逻辑卷管理器

LVM逻辑卷

LVM技术是在硬盘分区和文件系统之间添加了一个逻辑层，它提供了一个抽象的卷组，可以把多块硬盘进行卷组合并。这样一来，用户不必关心物理硬盘设备的底层架构和布局，就可以实现对硬盘分区的动态调整。　　

物理卷：Physical Volume，PV

卷组：Volume Group，VG

逻辑卷：Logical Volume，LV

基本单元：Physical Extent，PE，PE大小一般为4M。

注意：逻辑卷的大小一定是PE的倍数，即逻辑卷是由若干个PE组成。

 

 

部署逻辑卷

常用的LVM部署命令

功能/命令	物理卷管理	卷组管理	逻辑卷管理
扫描	pvscan	vgscan	lvscan
建立	pvcreate	vgcreate	lvcreate
显示	pvdisplay	vgdisplay	lvdisplay
删除	pvremove	vgremove	lvremove
扩展		vgextend	lvextend
缩小		vgreduce	lvreduce

1.创建物理卷

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[root@superwu10 ~]# pvcreate /dev/sdb /dev/sdc   //对硬盘创建物理卷   Physical volume "/dev/sdb" successfully created.   Physical volume "/dev/sdc" successfully created.

2.创建卷组

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[root@superwu10 ~]# vgcreate hehe /dev/sdb /dev/sdc  //创建卷组hehe，并将硬盘加入卷组   Volume group "hehe" successfully created[root@superwu10 ~]# ls -ld /dev/hehe  //卷组会自动在/dev目录中创建 drwxr-xr-x. 2 root root 80 Feb 10 06:58 /dev/hehe[root@superwu10 ~]# vgdisplay   //查看卷组信息   --- Volume group ---   VG Name               hehe   System ID               Format                lvm2   Metadata Areas        2   Metadata Sequence No  1   VG Access             read/write   VG Status             resizable   MAX LV                0   Cur LV                0   Open LV               0   Max PV                0   Cur PV                2   Act PV                2   VG Size               39.99 GiB   PE Size               4.00 MiB   Total PE              10238   Alloc PE / Size       0 / 0     Free  PE / Size       10238 / 39.99 GiB   VG UUID               Cma6sp-KXTQ-SoVz-xQ5c-rXCt-IrhY-nPdrVc        --- Volume group ---   VG Name               rhel   System ID               Format                lvm2   Metadata Areas        1   Metadata Sequence No  3   VG Access             read/write   VG Status             resizable   MAX LV                0   Cur LV                2   Open LV               2   Max PV                0   Cur PV                1   Act PV                1   VG Size               <19.00 GiB   PE Size               4.00 MiB   Total PE              4863   Alloc PE / Size       4863 / <19.00 GiB   Free  PE / Size       0 / 0     VG UUID               oMDZ59-DQqg-ok7A-YJMV-vXBO-KU5L-Slk8pe

3.创建逻辑卷

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[root@superwu10 ~]# lvcreate -n juan1 -l 30 hehe  //-n 表示创建逻辑卷的名称，-l 表示逻辑卷的大小为30个PE。在hehe卷组上创建逻辑卷juan1,大小为30*4M.   Logical volume "juan1" created. [root@superwu10 ~]# lvdisplay   //查看逻辑卷信息   --- Logical volume ---   LV Path                <strong>/dev/hehe/juan1   //逻辑卷存在与卷组下</strong>   LV Name                <strong>juan1</strong>   VG Name                <strong>hehe</strong>   LV UUID                9e0cRI-T9RO-PbBC-zQWd-Bfi2-rVUx-MPnrIW   LV Write Access        read/write   LV Creation host, time superwu10.10, 2022-02-10 06:57:31 +0800   LV Status              available   # open                 0   LV Size                <strong>120.00 MiB   //30个PE 30*4M=120M.</strong>   Current LE             30   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:2        --- Logical volume ---   LV Path                /dev/rhel/swap   LV Name                swap   VG Name                rhel   LV UUID                620uVZ-3mFM-BfSd-G2D7-H6QI-JmZi-nfEeWg   LV Write Access        read/write   LV Creation host, time superwu10.10, 2022-01-10 03:42:19 +0800   LV Status              available   # open                 2   LV Size                2.00 GiB   Current LE             512   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:1        --- Logical volume ---   LV Path                /dev/rhel/root   LV Name                root   VG Name                rhel   LV UUID                T0O43Y-pZqz-pKJH-BTI7-lChV-0RMU-iXS0UC   LV Write Access        read/write   LV Creation host, time superwu10.10, 2022-01-10 03:42:19 +0800   LV Status              available   # open                 1   LV Size                <17.00 GiB   Current LE             4351   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:0      [root@superwu10 ~]# lvcreate -n ceshi2 -L 150M hehe  //-L参数可直接指定创建卷的大小   Rounding up size to full physical extent<strong> 152.00 MiB</strong>   //卷大小如果不是4M的倍数，会自动微调为4的倍数。   Logical volume "ceshi2" created. [root@superwu10 ~]# lvdisplay   --- Logical volume ---   LV Path                /dev/hehe/juan1   LV Name                juan1   VG Name                hehe   LV UUID                9e0cRI-T9RO-PbBC-zQWd-Bfi2-rVUx-MPnrIW   LV Write Access        read/write   LV Creation host, time superwu10.10, 2022-02-10 06:57:31 +0800   LV Status              available   # open                 0   LV Size                120.00 MiB   Current LE             30   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:2        --- Logical volume ---   LV Path                <strong>/dev/hehe/ceshi2</strong>   LV Name                <strong>ceshi2</strong>   VG Name               <strong> hehe</strong>   LV UUID                k5jQcY-vC37-24XV-CtT5-28H4-zH6Z-ResmXr   LV Write Access        read/write   LV Creation host, time superwu10.10, 2022-02-10 06:58:56 +0800   LV Status              available   # open                 0   LV Size                <strong>152.00 MiB</strong>   Current LE            <strong> 38</strong>   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:3        --- Logical volume ---   LV Path                /dev/rhel/swap   LV Name                swap   VG Name                rhel   LV UUID                620uVZ-3mFM-BfSd-G2D7-H6QI-JmZi-nfEeWg   LV Write Access        read/write   LV Creation host, time superwu10.10, 2022-01-10 03:42:19 +0800   LV Status              available   # open                 2   LV Size                2.00 GiB   Current LE             512   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:1        --- Logical volume ---   LV Path                /dev/rhel/root   LV Name                root   VG Name                rhel   LV UUID                T0O43Y-pZqz-pKJH-BTI7-lChV-0RMU-iXS0UC   LV Write Access        read/write   LV Creation host, time superwu10.10, 2022-01-10 03:42:19 +0800   LV Status              available   # open                 1   LV Size                <17.00 GiB   Current LE             4351   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:0

4.格式化逻辑卷

如果使用了逻辑卷管理器，则不建议用XFS文件系统，因为XFS文件系统自身就可以使用xfs_growfs命令进行磁盘扩容。这虽然不比LVM灵活，但起码也够用。

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[root@superwu10 ~]# mkfs.ext4 /dev/hehe/juan1 mke2fs 1.44.3 (10-July-2018) Creating filesystem with 122880 1k blocks and 30720 inodes Filesystem UUID: 76a02fab-9c6c-4416-a82d-82f0d8e681a5 Superblock backups stored on blocks:     8193, 24577, 40961, 57345, 73729   Allocating group tables: done                            Writing inode tables: done                            Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done

5.挂载使用

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[root@superwu10 ~]# mkdir /opt/juan [root@superwu10 ~]# mount /dev/hehe/juan1 /opt/juan/ [root@superwu10 ~]# df -h Filesystem              Size  Used Avail Use% Mounted on devtmpfs                969M     0  969M   0% /dev tmpfs                   984M     0  984M   0% /dev/shm tmpfs                   984M  9.6M  974M   1% /run tmpfs                   984M     0  984M   0% /sys/fs/cgroup /dev/mapper/rhel-root    17G  4.2G   13G  25% / /dev/sr0                6.7G  6.7G     0 100% /media/cdrom /dev/sda1              1014M  153M  862M  15% /boot tmpfs                   197M   16K  197M   1% /run/user/42 tmpfs                   197M  3.5M  194M   2% /run/user/0 <strong>/dev/mapper/hehe-juan1  113M  1.6M  103M   2% /opt/juan</strong> [root@superwu10 ~]# echo "/dev/hehe/juan1 /opt/juan ext4 defaults 0 0" >> /etc/fstab

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[root@superwu10 ~]# cd /opt/juan/ [root@superwu10 juan]# ll total 12 drwx------. 2 root root 12288 Feb 10 07:13 lost+found [root@superwu10 juan]# touch test.txt [root@superwu10 juan]# ll total 13 drwx------. 2 root root 12288 Feb 10 07:13 lost+found <strong>-rw-r--r--. 1 root root     0 Feb 10 07:19 test.txt </strong>

扩容逻辑卷

用户在使用存储设备时感知不到设备底层的架构和布局，更不用关心底层是由多少块硬盘组成的，只要卷组中有足够的资源，就可以一直为逻辑卷扩容。扩容前请一定要记得卸载设备和挂载点的关联。

1.卸载设备

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[root@superwu ~]# umount /opt/data1 [root@superwu ~]# df -h Filesystem             Size  Used Avail Use% Mounted on devtmpfs               969M     0  969M   0% /dev tmpfs                  984M     0  984M   0% /dev/shm tmpfs                  984M  9.6M  974M   1% /run tmpfs                  984M     0  984M   0% /sys/fs/cgroup /dev/mapper/rhel-root   17G  3.9G   14G  23% / /dev/sr0               6.7G  6.7G     0 100% /media/cdrom /dev/sda1             1014M  152M  863M  15% /boot tmpfs                  197M   16K  197M   1% /run/user/42 tmpfs                  197M  3.5M  194M   2% /run/user/0

2.扩容逻辑卷

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[root@superwu ~]# lvextend -L 250M /dev/hehe/juan1  //扩容逻辑卷至250M   Rounding size to boundary between physical extents: 252.00 MiB.   Size of logical volume hehe/juan1 changed from 120.00 MiB (30 extents) to 252.00 MiB (63 extents).   Logical volume hehe/juan1 successfully resized.

3.检查硬盘的完整性，确认目录结构、内容和文件内容没有丢失。没有报错，为正常情况。　　

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[root@superwu ~]# e2fsck -f /dev/hehe/juan1 e2fsck 1.44.3 (10-July-2018) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information /dev/hehe/juan1: 12/30720 files (0.0% non-contiguous), 9530/122880 blocks

4.重置设备在系统中的容量。刚刚是对LV（逻辑卷）设备进行了扩容操作，但系统内核还没有同步到这部分新修改的信息，需要手动进行同步。

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[root@superwu ~]# resize2fs /dev/hehe/juan1 resize2fs 1.44.3 (10-July-2018) Resizing the filesystem on /dev/hehe/juan1 to 258048 (1k) blocks. The filesystem on /dev/hehe/juan1 is now 258048 (1k) blocks long.

5.重新挂载设备

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[root@superwu ~]# mount -a [root@superwu ~]# df -h Filesystem              Size  Used Avail Use% Mounted on devtmpfs                969M     0  969M   0% /dev tmpfs                   984M     0  984M   0% /dev/shm tmpfs                   984M  9.6M  974M   1% /run tmpfs                   984M     0  984M   0% /sys/fs/cgroup /dev/mapper/rhel-root    17G  3.9G   14G  23% / /dev/sr0                6.7G  6.7G     0 100% /media/cdrom /dev/sda1              1014M  152M  863M  15% /boot tmpfs                   197M   16K  197M   1% /run/user/42 tmpfs                   197M  3.5M  194M   2% /run/user/0 <strong>/dev/mapper/hehe-juan1  240M  2.1M  222M   1% /opt/data1</strong> [root@superwu ~]# lvdisplay   --- Logical volume ---   LV Path                <strong>/dev/hehe/juan1</strong>   LV Name                juan1   VG Name                hehe   LV UUID                KvHDJu-CMPo-uMwK-56B0-dMWB-hONK-OvhUxH   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-02-10 16:42:58 +0800   LV Status              available   # open                 1   <strong>LV Size                252.00 MiB   //已经扩容至252M</strong>   Current LE             63   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:2        --- Logical volume ---   LV Path                /dev/rhel/swap   LV Name                swap   VG Name                rhel   LV UUID                5r17mN-Xzxt-YbDv-fg9m-9JT1-AtsD-K6h5yZ   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-01-11 16:26:54 +0800   LV Status              available   # open                 2   LV Size                2.00 GiB   Current LE             512   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:1        --- Logical volume ---   LV Path                /dev/rhel/root   LV Name                root   VG Name                rhel   LV UUID                Ng4387-Ok4t-nWlF-zhtl-ahge-12Le-sk4mri   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-01-11 16:26:54 +0800   LV Status              available   # open                 1   LV Size                <17.00 GiB   Current LE             4351   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:0

缩小逻辑卷

缩容操作，有数据丢失风险，建议先备份数据再进行缩容。

在对LVM逻辑卷缩容前，首先要检查文件系统的完整性。

1.卸载LVM逻辑卷设备

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[root@superwu ~]# umount /opt/data1 [root@superwu ~]# df -h Filesystem             Size  Used Avail Use% Mounted on devtmpfs               969M     0  969M   0% /dev tmpfs                  984M     0  984M   0% /dev/shm tmpfs                  984M  9.6M  974M   1% /run tmpfs                  984M     0  984M   0% /sys/fs/cgroup /dev/mapper/rhel-root   17G  3.9G   14G  23% / /dev/sr0               6.7G  6.7G     0 100% /media/cdrom /dev/sda1             1014M  152M  863M  15% /boot tmpfs                  197M   16K  197M   1% /run/user/42 tmpfs                  197M  3.5M  194M   2% /run/user/0

2.检查文件系统完整性

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[root@superwu ~]# e2fsck -f /dev/hehe/juan1 e2fsck 1.44.3 (10-July-2018) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information /dev/hehe/juan1: 12/65536 files (0.0% non-contiguous), 14432/258048 blocks

3.通知内核缩减逻辑卷后的大小

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[root@superwu ~]# resize2fs /dev/hehe/juan1 <strong>150M</strong>   //将LVM逻辑卷缩减到150M resize2fs 1.44.3 (10-July-2018) Resizing the filesystem on /dev/hehe/juan1 to 153600 (1k) blocks. The filesystem on /dev/hehe/juan1 is now 153600 (1k) blocks long.

4.缩减LVM逻辑卷容量

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[root@superwu ~]# lvreduce -L <strong>150M</strong> /dev/hehe/juan1 //注意：缩减逻辑卷的大小应与通知内核时的大小相同。   Rounding size to boundary between physical extents: 152.00 MiB.   WARNING: Reducing active logical volume to 152.00 MiB.   THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce hehe/juan1? [y/n]:<strong> y  //需要二次确认</strong>   Size of logical volume hehe/juan1 changed from 252.00 MiB (63 extents) to 152.00 MiB (38 extents).   Logical volume hehe/juan1 successfully resized.

5.挂载并使用LVM逻辑卷

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[root@superwu ~]# mount -a [root@superwu ~]# df -h Filesystem              Size  Used Avail Use% Mounted on devtmpfs                969M     0  969M   0% /dev tmpfs                   984M     0  984M   0% /dev/shm tmpfs                   984M  9.6M  974M   1% /run tmpfs                   984M     0  984M   0% /sys/fs/cgroup /dev/mapper/rhel-root    17G  3.9G   14G  23% / /dev/sr0                6.7G  6.7G     0 100% /media/cdrom /dev/sda1              1014M  152M  863M  15% /boot tmpfs                   197M   16K  197M   1% /run/user/42 tmpfs                   197M  3.5M  194M   2% /run/user/0 <strong>/dev/mapper/hehe-juan1  142M  1.6M  130M   2% /opt/data1</strong> [root@superwu ~]# lvdisplay   --- Logical volume ---   LV Path                /dev/hehe/juan1   LV Name                juan1   VG Name                hehe   LV UUID                KvHDJu-CMPo-uMwK-56B0-dMWB-hONK-OvhUxH   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-02-10 16:42:58 +0800   LV Status              available   # open                 1  <strong> LV Size                152.00 MiB  //已经将逻辑卷缩小到150M</strong>   Current LE             38   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:2

逻辑卷快照

LVM还具备有“快照卷”功能，该功能类似于虚拟机软件的还原时间点功能。例如，对某一个逻辑卷设备做一次快照，如果日后发现数据被改错了，就可以利用之前做好的快照卷进行覆盖还原。LVM的快照卷功能有两个特点：

快照卷的容量必须等同于逻辑卷的容量；

快照卷仅一次有效，一旦执行还原操作后则会被立即自动删除。

1.查看要备份的LVM逻辑卷的大小、卷组的大小是否够用。

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[root@superwu ~]# lvdisplay   --- Logical volume ---   LV Path                /dev/hehe/juan1   LV Name                juan1   VG Name                hehe   LV UUID                KvHDJu-CMPo-uMwK-56B0-dMWB-hONK-OvhUxH   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-02-10 16:42:58 +0800   LV Status              available   # open                 1   LV Size                152.00 MiB   Current LE             38   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:2 [root@superwu data1]# vgdisplay   --- Volume group ---   VG Name               hehe   System ID               Format                lvm2   Metadata Areas        2   Metadata Sequence No  4   VG Access             read/write   VG Status             resizable   MAX LV                0   Cur LV                1   Open LV               1   Max PV                0   Cur PV                2   Act PV                2   VG Size               39.99 GiB   PE Size               4.00 MiB   Total PE              10238   Alloc PE / Size       38 / 152.00 MiB   Free  PE / Size       10200 / 39.84 GiB   VG UUID               jW63WM-Xw4t-dMIc-if0Y-6oPN-Rdbh-qloflg

2.创建快照

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[root@superwu data1]# lvcreate -s -n hehekuaizhao -L 150M /dev/hehe/juan1  //-s参数表示创建快照（对juan1逻辑卷创建快照），快照大小等于LVM逻辑卷。   Rounding up size to full physical extent 152.00 MiB   Logical volume "hehekuaizhao" created. [root@superwu data1]# lvdisplay   --- Logical volume ---   LV Path                /dev/hehe/juan1   LV Name                juan1   VG Name                hehe   LV UUID                KvHDJu-CMPo-uMwK-56B0-dMWB-hONK-OvhUxH   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-02-10 16:42:58 +0800   LV snapshot status     source of                          hehekuaizhao [active]  //此处可看到此逻辑卷已经被创建了快照hehekuaizhao   LV Status              available   # open                 1   LV Size                152.00 MiB   Current LE             38   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:2        --- Logical volume ---   LV Path                /dev/hehe/hehekuaizhao   LV Name                hehekuaizhao   VG Name                hehe   LV UUID                qfyr6Y-lg1h-9Hs1-G5VQ-9svJ-kDie-NS1v67   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-02-10 17:33:12 +0800   LV snapshot status     active destination for juan1   //此处可看到本快照是基于juan1创建的   LV Status              available   # open                 0   LV Size                152.00 MiB   Current LE             38   COW-table size         152.00 MiB   COW-table LE           38   Allocated to snapshot  0.01%   Snapshot chunk size    4.00 KiB   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:5

3.还原快照

lvconvert命令用于管理逻辑卷的快照，语法格式为“lvconvert [参数]快照卷名称”。

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[root@superwu ~]#cd /opt/data1     //修改LVM逻辑卷中的内容 [root@superwu data1]# touch ceshi1 [root@superwu data1]# touch ceshi2 [root@superwu data1]# touch ceshi3    [root@superwu data1]# ll total 17 -rw-r--r--. 1 root root     0 Feb 10 17:36 ceshi1 -rw-r--r--. 1 root root     0 Feb 10 17:36 ceshi2 -rw-r--r--. 1 root root     0 Feb 10 17:36 ceshi3 -rw-r--r--. 1 root root    10 Feb 10 17:30 hehe drwx------. 2 root root 12288 Feb 10 16:44 lost+found   [root@superwu data1]cd ~<br><br>还原快照需要先卸载LVM逻辑卷设备 [root@superwu ~]# umount /opt/data1  //卸载逻辑卷 [root@superwu ~]# df -h Filesystem             Size  Used Avail Use% Mounted on devtmpfs               969M     0  969M   0% /dev tmpfs                  984M     0  984M   0% /dev/shm tmpfs                  984M  9.6M  974M   1% /run tmpfs                  984M     0  984M   0% /sys/fs/cgroup /dev/mapper/rhel-root   17G  3.9G   14G  23% / /dev/sr0               6.7G  6.7G     0 100% /media/cdrom /dev/sda1             1014M  152M  863M  15% /boot tmpfs                  197M   16K  197M   1% /run/user/42 tmpfs                  197M  3.5M  194M   2% /run/user/0 [root@superwu ~]# lvconvert --merge /dev/hehe/hehekuaizhao   //将逻辑卷恢复到hehekuaizhao快照   Merging of volume hehe/hehekuaizhao started.   hehe/juan1: Merged: 100.00% [root@superwu ~]# mount -a   //挂载逻辑卷 [root@superwu ~]# df -h Filesystem              Size  Used Avail Use% Mounted on devtmpfs                969M     0  969M   0% /dev tmpfs                   984M     0  984M   0% /dev/shm tmpfs                   984M  9.6M  974M   1% /run tmpfs                   984M     0  984M   0% /sys/fs/cgroup /dev/mapper/rhel-root    17G  3.9G   14G  23% / /dev/sr0                6.7G  6.7G     0 100% /media/cdrom /dev/sda1              1014M  152M  863M  15% /boot tmpfs                   197M   16K  197M   1% /run/user/42 tmpfs                   197M  3.5M  194M   2% /run/user/0 /dev/mapper/hehe-juan1  142M  1.6M  130M   2% /opt/data1 [root@superwu ~]# cd /opt/data1/   [root@superwu data1]# ll total 14  -rw-r--r--. 1 root root    10 Feb 10 17:30 hehe    //快照已恢复 drwx------. 2 root root 12288 Feb 10 16:44 lost+found

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[root@superwu data1]# lvdisplay    //快照被恢复后会自动删除，即快照只一次有效   --- Logical volume ---   LV Path                /dev/hehe/juan1   LV Name                juan1   VG Name                hehe   LV UUID                KvHDJu-CMPo-uMwK-56B0-dMWB-hONK-OvhUxH   LV Write Access        read/write   LV Creation host, time superwu.10, 2022-02-10 16:42:58 +0800   LV Status              available   # open                 1   LV Size                152.00 MiB   Current LE             38   Segments               1   Allocation             inherit   Read ahead sectors     auto   - currently set to     8192   Block device           253:2

删除逻辑卷

删除逻辑卷需要执行严格的操作步骤，不能颠倒顺序。删除逻辑卷 --> 卷组 --> 物理卷设备。

1.卸载逻辑卷，删除开机自动挂载

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[root@superwu ~]# umount /opt/data1 [root@superwu ~]# vim /etc/fstab [root@superwu ~]# cat /etc/fstab   # # /etc/fstab # Created by anaconda on Tue Jan 11 03:26:57 2022 # # Accessible filesystems, by reference, are maintained under '/dev/disk/'. # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info. # # After editing this file, run 'systemctl daemon-reload' to update systemd # units generated from this file. # /dev/mapper/rhel-root   /                       xfs     defaults        0 0 UUID=d7f53471-c95f-44f2-aafe-f86bd5ecebd7 /boot                   xfs     defaults        0 0 /dev/mapper/rhel-swap   swap                    swap    defaults        0 0 /dev/cdrom             /media/cdrom             iso9660 defaults        0 0

2.删除逻辑卷

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[root@superwu ~]# lvremove /dev/hehe/juan1 Do you really want to remove active logical volume hehe/juan1? [y/n]: y   //需要二次确认   Logical volume "juan1" successfully removed

3.删除卷组

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1 2	[root@superwu ~]# vgremove hehe   //直接写卷组名称即可，不需要写完整路径   Volume group "hehe" successfully removed

4.删除物理卷

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[root@superwu ~]# pvremove /dev/sdb /dev/sdc    Labels on physical volume "/dev/sdb" successfully wiped.   Labels on physical volume "/dev/sdc" successfully wiped.

删除后，可执行lvdisplay、vgdisplay、pvdisplay命令查看删除是否成功。