LVM-COW写实备份
[root@localhost ~]# fdisk -l /dev/sdb /dev/sdc | grep "LVM"
/dev/sdb1 1 9660 77593918+ 8e Linux LVM
/dev/sdc1 1 9660 77593918+ 8e Linux LVM
创建物理卷:
[root@localhost ~]# pvcreate /dev/sdb1
Physical volume "/dev/sdb1" successfully created
[root@localhost ~]# pvcreate /dev/sdc1
Physical volume "/dev/sdc1" successfully created
创建卷组:
[root@localhost ~]# vgcreate mail_store /dev/sdb1 /dev/sdc1
Volume group "mail_store" successfully created
创建逻辑卷:
[root@localhost ~]# lvcreate -L 60G -n mail mail_store
Logical volume "mail" created
[root@localhost ~]# mkfs -t ext4 /dev/mail_store/mail
……
逻辑卷扩容:
[root@localhost ~]# lvextend -L +10G /dev/mail_store/mail
[root@localhost ~]# resize2fs /dev/mail_store/mail (物理分区或者挂在点都可)
如果本身VG不够大,也可以扩大VG
[root@localhost ~]# vgextend mail_store(扩大谁) /dev/vda5(从哪扩大)
逻辑卷减小:
[root@localhost ~]# umount /media
[root@localhost ~]# resize2fs -p -d 2 /dev/mail_store/mail 1G (缩小1G)
[root@localhost ~]# e2fsck -f /dev/dev/mail_store/mail (缩小前检查磁盘)
[root@localhost ~]# lvreduce -L 1G /dev/mail_store/mail
[root@localhost ~]# lvchange -an /dev/mail_store/mail (下线)
[root@localhost ~]# lvchange -ay /dev/mail_store/mail (生产模式)
[root@localhost ~]# mount -a (重新挂载)
逻辑卷快照:
[root@localhost ~]# umount /media/
[root@localhost ~]# lvcreate -s -L 100M -n homebak /dev/vgsrv/home(对谁备份)
--------lvs 会多出来一个homebak
[root@localhost ~]# mkdir /mnt/homebak
[root@localhost ~]# mount -o ro /dev/vgsrv/home /mnt/homebak
--------修改home目录
[root@localhost ~]# tar zcvf /backup/homebak.tar.gz /mnt/homebak
[root@localhost ~]# umount /mnt/homebak
[root@localhost ~]# lvremove /dev/vgsrv/home
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