linux系统LVM管理-逻辑卷扩容
总结：多个磁盘/分区/raid-->多个物理卷PV-->合成卷组VG-->从VG划分出逻辑卷LV-->格式化LV，挂载使用。
#lsblk #查看硬盘和分区分布
fdisk -l |grep /dev
#创建pv物理卷
pvcreate /dev/sdb
pvcreate /dev/sdc
#查看pv物理卷
pvs
#创建vg卷组
vgcreate datavg /dev/sdb
vgcreate datavg2 /dev/sdc
#查看vg卷组
vgs
#创建lv逻辑卷
lvcreate -n a_lv -L 10G datavg
lvcreate -n b_lv -L 5G datavg
lvcreate -n c_lv -L 3G datavg
lvcreate -n d_lv -L 1G datavg
lvcreate -n e_lv -L 10G datavg2
lvcreate -n f_lv -L 8G datavg2
#查看lv逻辑卷
lvs
#格式化lv逻辑卷
mkfs.ext4 /dev/datavg/a_lv
mkfs.ext4 /dev/datavg/b_lv
mkfs.ext4 /dev/datavg/c_lv
mkfs.ext4 /dev/datavg/d_lv
mkfs.ext4 /dev/datavg/e_lv
mkfs.ext4 /dev/datavg2/e_lv
mkfs.ext4 /dev/datavg2/f_lv
#创建lv逻辑卷所挂载目录
mkdir /lv_a
mkdir /lv_b
mkdir /lv_c
mkdir /lv_d
mkdir /lv_e
mkdir /lv_f
########## mkdir /lv_{a,b,c,d,e,f}
#挂载lv逻辑卷
mount /dev/datavg/a_lv /lv_a
mount /dev/datavg/b_lv /lv_b
mount /dev/datavg/c_lv /lv_c
mount /dev/datavg/d_lv /lv_d
mount /dev/datavg2/e_lv /lv_e
mount /dev/datavg2/f_lv /lv_f
#配置lv逻辑卷开机自动挂载
vi /etc/fstab
/dev/datavg/a_lv /lv_a ext4 defaults 1 2
/dev/datavg/b_lv /lv_b ext4 defaults 1 2
/dev/datavg/c_lv /lv_c ext4 defaults 1 2
/dev/datavg/d_lv /lv_d ext4 defaults 1 2
/dev/datavg2/e_lv /lv_e ext4 defaults 1 2
/dev/datavg2/f_lv /lv_f ext4 defaults 1 2
#[root@test1-119 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/centos-root 26G 4.4G 22G 17% /
devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs 1.9G 9.5M 1.9G 1% /run
tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 1014M 169M 846M 17% /boot
/dev/mapper/datavg-c_lv 2.9G 9.0M 2.8G 1% /lv_c
/dev/mapper/datavg-d_lv 976M 2.6M 907M 1% /lv_d
/dev/mapper/datavg-b_lv 4.8G 20M 4.6G 1% /lv_b
/dev/mapper/datavg-a_lv 9.8G 37M 9.2G 1% /lv_a
/dev/mapper/datavg2-e_lv 9.8G 37M 9.2G 1% /lv_e
/dev/mapper/datavg2-f_lv 7.8G 36M 7.3G 1% /lv_f
tmpfs 380M 12K 380M 1% /run/user/42
tmpfs 380M 0 380M 0% /run/user/0
#####################lv扩容
[root@202 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/rhel-root 17G 1.9G 16G 12% /
devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs 1.9G 8.9M 1.9G 1% /run
tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sr0 3.8G 3.8G 0 100% /mnt/cdrom
/dev/sda1 1014M 142M 873M 14% /boot
tmpfs 380M 0 380M 0% /run/user/0
/dev/mapper/vg1-lvm1 961M 2.5M 910M 1% /mnt/lvm1
给lvm1扩容2G
[root@202 ~]# lvextend -L +2G /dev/vg1/lvm1
Size of logical volume vg1/lvm1 changed from 1000.00 MiB (250 extents) to <2.98 GiB (762 extents).
Logical volume vg1/lvm1 successfully resized.
用resize2fs扩容ext的文件系统；如果文件系统为xfs则用xfs_growfs来扩容文件系统，XFS不支持缩小，只支持扩大。
###linux6 [root@202 ~]# resize2fs /dev/vg1/lvm1
###linux7 [root@localhost ~]# xfs_growfs /dev/rhel/root
resize2fs 1.42.9 (28-Dec-2013)
Filesystem at /dev/vg1/lvm1 is mounted on /mnt/lvm1; on-line resizing required
old_desc_blocks = 8, new_desc_blocks = 24
The filesystem on /dev/vg1/lvm1 is now 3121152 blocks long.
通过df -TH查看扩容结果，可以看到从1G变成了3G
[root@202 ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/rhel-root 17G 1.9G 16G 12% /
devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs 1.9G 0 1.9G 0% /dev/shm
tmpfs 1.9G 8.9M 1.9G 1% /run
tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sr0 3.8G 3.8G 0 100% /mnt/cdrom
/dev/sda1 1014M 142M 873M 14% /boot
tmpfs 380M 0 380M 0% /run/user/0
/dev/mapper/vg1-lvm1 2.9G 3.1M 2.8G 1% /mnt/lvm1
