[转]linux LVM配置
? Physical volume "/dev/hdb2" successfully created
[root@redhat ~]# pvscan
? PV /dev/hdb1???????? lvm2 [95.95 MB]
? PV /dev/hdb2???????? lvm2 [95.98 MB]
? Total: 2 [191.92 MB] / in use: 0 [0?? ] / in no VG: 2 [191.92 MB]
[root@redhat ~]# pvdisplay
? --- NEW Physical volume ---
? PV Name?????????????? /dev/hdb1
? VG Name??????????????
? PV Size?????????????? 95.95 MB
? Allocatable?????????? NO
? PE Size (KByte)?????? 0
? Total PE????????????? 0
? Free PE?????????????? 0
? Allocated PE????????? 0
? PV UUID?????????????? 2Ni0Tx-oeSy-zGUP-t7KG-Fh22-0BUi-iyPhhQ
??
? --- NEW Physical volume ---
? PV Name?????????????? /dev/hdb2
? VG Name??????????????
? PV Size?????????????? 95.98 MB
? Allocatable?????????? NO
? PE Size (KByte)?????? 0
? Total PE???????????????? ?0
? Free PE????????????????? 0
? Allocated PE????????? ?0
? PV UUID?????????????? 2XLXfY-V3L2-Mtsl-79U4-ovuJ-YaQf-YV9qHs
四、创建LVM的卷组VG
1．相关命令
vgcreate?? 创建VG
vgscan???? 扫描VG
vgdispaly
vgextend
vgreduce??
vgchange
vgremove
2．创建逻辑卷VG
[root@redhat ~]# vgcreate vg0 /dev/hdb1 /dev/hdb2
? Volume group "vg0" successfully created
[root@redhat ~]# vgscan
? Reading all physical volumes.? This may take a while...
? Found volume group "vg0" using metadata type lvm2
[root@redhat ~]# vgdisplay
? --- Volume group ---
? VG Name?????????????? vg0
? 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?????????????? 184.00 MB
? PE Size?????????????? 4.00 MB?? /*分配的块的大小默认为4M*/
? Total PE????????????? 46
? Alloc PE / Size?????? 0 / 0??
? Free? PE / Size?????? 46 / 184.00 MB
? VG UUID?????????????? kL5CGk-5Odk-r3PK-9q0A-s94h-OHv4-BojBnH增加VG容量到1TB的方法：
vgcreate -s 16M vg0 /dev/hdb1 /dev/hdb2
3．删除与添加逻辑卷
[root@redhat ~]# vgreduce vg0 /dev/hdb2
? Removed "/dev/hdb2" from volume group "vg0"
[root@redhat ~]# vgextend vg0 /dev/hdb2
? Volume group "vg0" successfully extended
五、创建LVM的逻辑卷LV
1．相关命令
lvcreate
lvscan
lvdisplay
lvextend
lvreduce
lvremove
lvresize
2．创建逻辑卷LV
[root@redhat ~]# lvcreate -L 184M -n data vg0
? Logical volume "data" created
[root@redhat ~]# lvscan
? ACTIVE???? '/dev/vg0/data' [184.00 MB] inherit
[root@redhat ~]# lvdisplay
? --- Logical volume ---
? LV Name??????????????? /dev/vg0/data
? VG Name??????????????? vg0
? LV UUID??????????????? HNKO5d-yRre-qVnP-ZT8D-fXir-XTeM-r6WjDX
? LV Write Access??????? read/write
? LV Status????????????? available
? # open???????????????? 0
? LV Size??????????????? 184.00 MB
? Current LE???????????? 46
? Segments?????????????? 2
? Allocation???????????? inherit
? Read ahead sectors???? 0
? Block device?????????? 253:0
六、挂载LVM的逻辑卷LV
lv的格式化:
mkfs.ext3 /dev/vg0/data
mdkir /mnt/lvm
mount /dev/vg0/data /mnt/lvm
[root@redhat ~]# ls /mnt/lvm
lost+found
[root@redhat ~]# df -T
文件系统????? 类型???? 1K-块??????? 已用???? 可用 已用% 挂载点
/dev/hda3???? ext3???? 7625092?? 2219460?? 5012040? 31% /
/dev/hda1???? ext3????? 101086???? 10006???? 85861? 11% /boot
tmpfs??????? tmpfs????? 150108???????? 0??? 150108?? 0% /dev/shm
/dev/mapper/vg0-data
????????????? ext3????? 182469????? 5664??? 167385?? 4% /mnt/lvm
七、LVM的容量调整
LVM的容量调整可以在多个环节进行调整，比如：可以在物理卷上，VG上，以及LV上，都可以进行容量的扩展，这也是LVM它的一个优势所在。
1．添加物理卷
首先应卸载在使用过程中的LV，然后必须保证该磁盘的类型是lvm类型，才能添加进来。
[root@redhat ~]# umount /dev/vg0/data
[root@redhat ~]# pvcreate /dev/hdb3
? Physical volume "/dev/hdb3" successfully created
[root@redhat ~]# pvscan
? PV /dev/hdb1?? VG vg0?? lvm2 [92.00 MB / 0??? free]
? PV /dev/hdb2?? VG vg0?? lvm2 [92.00 MB / 0??? free]
? PV /dev/hdb3??????????? lvm2 [95.98 MB]
? Total: 3 [279.98 MB] / in use: 2 [184.00 MB] / in no VG: 1 [95.98 MB]
2．添加VG的容量
把上面新添加的LVM磁盘加入到vg0卷组中。
[root@redhat ~]# vgextend vg0 /dev/hdb3
? Volume group "vg0" successfully extended
[root@redhat ~]# vgdisplay
? --- Volume group ---
? VG Name?????????????? vg0
? System ID????????????
? Format??????????????? lvm2
? Metadata Areas??????? 3
? Metadata Sequence No? 5
? VG Access???????????? read/write
? VG Status???????????? resizable
? MAX LV??????????????? 0
? Cur LV??????????????? 1
? Open LV?????????????? 0
? Max PV??????????????? 0
? Cur PV??????????????? 3
? Act PV??????????????? 3
? VG Size?????????????? 276.00 MB
? PE Size?????????????? 4.00 MB
? Total PE????????????? 69
? Alloc PE / Size?????? 46 / 184.00 MB
? Free? PE / Size?????? 23 / 92.00 MB
? VG UUID?????????????? kL5CGk-5Odk-r3PK-9q0A-s94h-OHv4-BojBnH
3．添加入LV中VG增珈的容量
把新加入LVM磁盘的容量加入LV中。
[root@redhat ~]# lvextend -L +92M /dev/vg0/data
? Extending logical volume data to 276.00 MB
? Logical volume data successfully resized
[root@redhat ~]# lvscan
? ACTIVE????? '/dev/vg0/data' [276.00 MB] inherit
[root@redhat ~]# resize2fs -f /dev/vg0/data
resize2fs 1.39 (29-May-2006)
Resizing the filesystem on /dev/vg0/data to 282624 (1k) blocks.
The filesystem on /dev/vg0/data is now 282624 blocks long.
如果不做这一步的话，在实现挂载的时候，发现LV的容量没有真正的加入进LV卷中，因为相关信息写入到了磁盘超级块中。
4．挂载使用
[root@redhat ~]# mount /dev/vg0/data /mnt/lvm
[root@redhat ~]# df
文件系统?????????????? 1K-块??????? 已用???? 可用 已用% 挂载点
/dev/hda3????????????? 7625092?? 2219468?? 5012032? 31% /
/dev/hda1?????????????? 101086???? 10006???? 85861? 11% /boot
tmpfs?????????????????? 150108???????? 0??? 150108?? 0% /dev/shm
/dev/mapper/vg0-data??? 273569????? 6168??? 256097?? 3% /mnt/lvm
LVM的卸载
八、LVM的卸载方法
如果不想使用LVM的话,可以卸载它, 卸载的方法与分区的删除方法类似，就是最后创建的最先删除。顺序如下：
先删除LV
再删除VG
最后PV
以前的LVM的分区应用fdisk转换成其它类型的文件系统，当普通分区使用。
九、LVM的卸载过程
1．umount取消挂载
[root@redhat ~]# df
文件系统?????????????? 1K-块??????? 已用???? 可用 已用% 挂载点
/dev/hda3????????????? 7625092?? 2219468?? 5012032? 31% /
/dev/hda1?????????????? 101086???? 10006???? 85861? 11% /boot
tmpfs?????????????????? 150108???????? 0??? 150108?? 0% /dev/shm
/dev/mapper/vg0-data??? 273569????? 6168??? 256097?? 3% /mnt/lvm
[root@redhat ~]# umount /mnt/lvm
2．删除LV逻辑卷
[root@redhat ~]# lvremove /dev/vg0/data
Do you really want to remove active logical volume "data"? [y/n]: y
? Logical volume "data" successfully removed
3．删除VG卷组
[root@redhat ~]# vgchange -a n vg0
? 0 logical volume(s) in volume group "vg0" now active
说明：把vg0转换成休眠状态，实验中这一步可以不用。
[root@redhat ~]# vgremove vg0
? Volume group "vg0" successfully removed
4．删除PV
[root@redhat ~]# pvscan 查看pv的情况
? PV /dev/hdb1???????? lvm2 [95.95 MB]
? PV /dev/hdb2???????? lvm2 [95.98 MB]
? PV /dev/hdb3???????? lvm2 [95.98 MB]
? Total: 3 [287.90 MB] / in use: 0 [0?? ] / in no VG: 3 [287.90 MB]
[root@redhat ~]# pvremove /dev/hdb1 /dev/hdb2 /dev/hdb3
? Attempt to close device '/dev/cdrom' which is not open.
? Labels on physical volume "/dev/hdb1" successfully wiped
? Labels on physical volume "/dev/hdb2" successfully wiped
? Labels on physical volume "/dev/hdb3" successfully wiped
5．最后就是用fdisk修改磁盘的类型了。
十、 LVM配置总结
在LVM的学习过程中，经历过了很长的时间，主要是对LVM配置的方法，以及过程层次结构不是很清析。这次的配置过程中，按照配置的过程完整的执行了一次，对lvm内容了解了更进一步。如有实例的内容再次补充。
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转自：http://blog.csdn.net/meboy88scofiled/article/details/5614485
