lvm简单实用
author：skate
time：2009/04/03
os： centos4.7
ram：32G
disk：4块300G硬盘
作为一个系统设计者来说，前期规划很重要，既要满足现在的要求有要方便以后的扩展
我的硬盘系统做的是 raid10， 考虑到以后的空间扩展，我把可能变化的数据区做成卷组
方便的以后的扩展和管理，因为目前来说，空间具体应用到什么程度，还不完全清楚，我
预留了175G的空间为空闲
查看目前的内存：
Last login: Fri Apr 3 02:33:37 2009 from 192.168.2.87
[root@ticketb ~]# free -g
total used free shared buffers cached
Mem: 31 0 31 0 0 0
-/+ buffers/cache: 0 31
Swap: 30 0 30
查看目前的磁盘空间：
[root@ticketb ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 981M 202M 730M 22% /
none 16G 0 16G 0% /dev/shm
/dev/sda9 2.9G 37M 2.7G 2% /tmp
/dev/sda7 4.9G 1.9G 2.7G 42% /usr
/dev/sda8 2.9G 116M 2.7G 5% /var
查看磁盘的分区情况（在安装操作系统的时候，我已经分好区了）：
[root@ticketb ~]# fdisk -l
Disk /dev/sda: 598.8 GB, 598879502336 bytes
255 heads, 63 sectors/track, 72809 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Device Boot Start End Blocks Id System
/dev/sda1 * 1 127 1020096 83 Linux
/dev/sda2 128 25623 204796620 8e Linux LVM
/dev/sda3 25624 44745 153597465 8e Linux LVM
/dev/sda4 44746 72809 225424080 5 Extended
/dev/sda5 44746 47295 20482843+ 8e Linux LVM
/dev/sda6 47296 49207 15358108+ 82 Linux swap
/dev/sda7 49208 49844 5116671 83 Linux
/dev/sda8 49845 50226 3068383+ 83 Linux
/dev/sda9 50227 50608 3068383+ 83 Linux
/dev/sda10 50609 52676 16611178+ 82 Linux swap
lvm的创建
1. 创建物理卷
[root@ticketb ~]# pvcreate /dev/sda2
Physical volume "/dev/sda2" successfully created
[root@ticketb ~]# pvcreate /dev/sda3
Physical volume "/dev/sda3" successfully created
[root@ticketb ~]# pvcreate /dev/sda5
Physical volume "/dev/sda5" successfully created
查看所创建的物理卷：
[root@ticketb ~]# pvscan
PV /dev/sda2 lvm2 [195.31 GB]
PV /dev/sda3 lvm2 [146.48 GB]
PV /dev/sda5 lvm2 [19.53 GB]
Total: 3 [361.33 GB] / in use: 0 [0 ] / in no VG: 3 [361.33 GB]
2.创建卷组：
[root@ticketb ~]# vgcreate -s 256m vghome /dev/sda5
Volume group "vghome" successfully created
[root@ticketb ~]# vgcreate -s 256m vgoradata /dev/sda3
Volume group "vgoradata" successfully created
[root@ticketb ~]# vgcreate -s 256m vgbackup /dev/sda2
Volume group "vgbackup" successfully created
查看所创建的卷组：
[root@ticketb ~]# vgscan
Reading all physical volumes. This may take a while...
Found volume group "vghome" using metadata type lvm2
Found volume group "vgoradata" using metadata type lvm2
Found volume group "vgbackup" using metadata type lvm2
显示创建的卷组的详细信息：
[root@ticketb ~]# vgdisplay vghome
--- Volume group ---
VG Name vghome
System ID
Format lvm2
Metadata Areas 1
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 1
Act PV 1
VG Size 19.50 GB
PE Size 256.00 MB
Total PE 78
Alloc PE / Size 0 / 0
Free PE / Size 78 / 19.50 GB
VG UUID s6X9cb-ajYj-E66N-w8EZ-Lbpc-mmL7-GqDZ5p
3.创建逻辑卷
[root@ticketb ~]# lvcreate -L 19.5G -n lvhome vghome
Logical volume "lvhome" created
下面是没创建成功 ，因为空间不够
[root@ticketb ~]# lvcreate -L 195.31G -n lvbackup vgbackup
Rounding up size to full physical extent 195.50 GB
Insufficient free extents (781) in volume group vgbackup: 782 required
[root@ticketb ~]# lvcreate -L 195.25G -n lvbackup vgbackup
Logical volume "lvbackup" created
[root@ticketb ~]# lvcreate -L 146.25G -n lvoradata vgoradata
Logical volume "lvoradata" created
查看创建的逻辑卷
[root@ticketb ~]# lvscan
ACTIVE '/dev/vghome/lvhome' [19.50 GB] inherit
ACTIVE '/dev/vgoradata/lvoradata' [146.25 GB] inherit
ACTIVE '/dev/vgbackup/lvbackup' [195.25 GB] inherit
[root@ticketb ~]# vgdisplay vgbackup
--- Volume group ---
VG Name vgbackup
System ID
Format lvm2
Metadata Areas 1
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 1
Act PV 1
VG Size 195.25 GB
PE Size 256.00 MB
Total PE 781
Alloc PE / Size 0 / 0
Free PE / Size 781 / 195.25 GB
VG UUID kQBMDg-6M24-69bm-gc3I-bIk9-Jg00-XyXklk
[root@ticketb ~]# vgdisplay vgoradata
--- Volume group ---
VG Name vgoradata
System ID
Format lvm2
Metadata Areas 1
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 1
Act PV 1
VG Size 146.25 GB
PE Size 256.00 MB
Total PE 585
Alloc PE / Size 0 / 0
Free PE / Size 585 / 146.25 GB
VG UUID m4ZW7x-oaAt-5g0X-J6El-Yv62-wxEc-OojYbQ
4. 创建文件系统
[root@ticketb ~]# mkfs.ext3 /dev/vghome/lvhome
mke2fs 1.35 (28-Feb-2004)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
2555904 inodes, 5111808 blocks
255590 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
156 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000
Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 21 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
[root@ticketb ~]# mkfs.ext3 /dev/vgoradata/lvoradata
mke2fs 1.35 (28-Feb-2004)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
19169280 inodes, 38338560 blocks
1916928 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
1170 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872
Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 29 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
[root@ticketb ~]# mkfs.ext3 /dev/vgbackup/lvbackup
mke2fs 1.35 (28-Feb-2004)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
25591808 inodes, 51183616 blocks
2559180 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=4294967296
1562 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632, 2654208,
4096000, 7962624, 11239424, 20480000, 23887872
Writing inode tables: done
Creating journal (8192 blocks): done
Writing superblocks and filesystem accounting information: done
This filesystem will be automatically checked every 28 mounts or
180 days, whichever comes first. Use tune2fs -c or -i to override.
5. 挂载文件系统：
[root@ticketb ~]# mkdir -p /u01/oradata
[root@ticketb ~]# mkdir -p /u01/backup
[root@ticketb ~]# ls
anaconda-ks.cfg Desktop install.log install.log.syslog
[root@ticketb ~]# mount -t ext3 /dev/vghome/lvhome /home
[root@ticketb ~]# mount -t ext3 /dev/vgoradata/lvoradata /u01/oradata
[root@ticketb ~]# mount -t ext3 /dev/vgbackup/lvbackup /u01/backup
查看挂载情况：
[root@ticketb ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 981M 202M 730M 22% /
none 16G 0 16G 0% /dev/shm
/dev/sda9 2.9G 37M 2.7G 2% /tmp
/dev/sda7 4.9G 1.9G 2.7G 42% /usr
/dev/sda8 2.9G 116M 2.7G 5% /var
/dev/mapper/vghome-lvhome
20G 76M 19G 1% /home
/dev/mapper/vgoradata-lvoradata
144G 92M 137G 1% /u01/oradata
/dev/mapper/vgbackup-lvbackup
193G 92M 183G 1% /u01/backup
[root@ticketb ~]#
让系统启动后自动挂载lvm，可以编辑文件/etc/fstab
我的系统的挂载情况如下：
root@ticketA ~]# more /etc/fstab
# This file is edited by fstab-sync - see 'man fstab-sync' for details
LABEL=/ / ext3 defaults 1 1
none /dev/pts devpts gid=5,mode=620 0 0
none /dev/shm tmpfs defaults 0 0
none /proc proc defaults 0 0
none /sys sysfs defaults 0 0
LABEL=/tmp /tmp ext3 defaults 1 2
LABEL=/usr /usr ext3 defaults 1 2
LABEL=/var /var ext3 defaults 1 2
LABEL=SWAP-sda6 swap swap defaults 0 0
/dev/sda10 swap swap defaults 0 0
/dev/mapper/vghome-lvhome /home ext3 defaults 1 2
/dev/mapper/vgoradata-lvoradata /u01/oradata ext3 defaults 1 2
/dev/mapper/vgbackup-lvbackup /u01/backup ext3 defaults 1 2
/dev/scd0 /media/cdrom auto pamconsole,fscontext=system_u:object_r:re
movable_t,exec,noauto,managed 0 0
[root@ticketA ~]#
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