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unit5 使用逻辑卷管理灵活存储
###LVM创建###
[root@station ~]# mkdir /weixindata ##建立目录[root@station ~]# pvcreate /dev/vdb1 ##建立pv Physical volume /dev/vdb1 notfound Can't open /dev/vdb1 exclusively. Mounted filesystem?[root@station ~]# vgcreate vg0 /dev/vdb1 ##建立vg Physical volume /dev/vdb1 notfound Physical volume /dev/vdb1 notfound Can't open /dev/vdb1 exclusively. Mounted filesystem? Unable to add physical volume'/dev/vdb1' to volume group 'vg0'.[root@station ~]# mkfs.xfs /dev/vg0 /dev/vg0: No such file or directory Usage: mkfs.xfs /* blocksize */ [-blog=n|size=num] /* metadata */ [-m crc=[0|1] /* data subvol */ [-dagcount=n,agsize=n,file,name=xxx,size=num, (sunit=value,swidth=value|su=num,sw=num|noalign), sectlog=n|sectsize=num /* force overwrite */ [-f] /* inode size */ [-ilog=n|perblock=n|size=num,maxpct=n,attr=0|1|2, projid32bit=0|1] /* no discard */ [-K] /* log subvol */ [-lagnum=n,internal,size=num,logdev=xxx,version=n sunit=value|su=num,sectlog=n|sectsize=num, lazy-count=0|1] /* label */ [-L label (maximum 12characters)] /* naming */ [-nlog=n|size=num,version=2|ci,ftype=0|1] /* no-op info only */ [-N] /* prototype file */ [-p fname] /* quiet */ [-q] /* realtime subvol */ [-r extsize=num,size=num,rtdev=xxx] /* sectorsize */ [-slog=n|size=num] /* version */ [-V] devicename is required unless -d name=xxx is given. is xxx (bytes), xxxs (sectors), xxxb (fs blocks), xxxk (xxxKiB), xxxm (xxx MiB), xxxg (xxx GiB), xxxt(xxx TiB) or xxxp (xxx PiB). is xxx (512 byte blocks).[root@station ~]# mdadm -D /dev/md0 ##查看设备信息 mdadm: md device /dev/md0 does not appear to be active.[root@station ~]# mdadm -S /dev/md0 ##停止此设备 mdadm: stopped /dev/md0[root@station ~]# mdadm -a /dev/md0 /dev/vdb2 ##添加一个新设备 [root@station ~]# vgcreate vg0 /dev/vdb1 Volume group "vg0"successfully created[root@station ~]# lvcreate -L 300M -n lv0 vg0 ##创建300M的lv0在vg0下 Logical volume "lv0"created[root@station ~]# mkfs.xfs /dev/vg0/lv0 ##格式化 meta-data=/dev/vg0/lv0 isize=256 agcount=4,agsize=19200 blks = sectsz=512 attr=2, projid32bit=1 = crc=0 data = bsize=4096 blocks=76800, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=0 log =internal log bsize=4096 blocks=853, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0,rtextents=0[root@station ~]# mount /dev/vg0/lv0 /weixindata/ ##挂载 [root@station ~]# ll /dev/mapper/vg0-lv0 lrwxrwxrwx. 1 root root 7 Apr 22 03:52 /dev/mapper/vg0-lv0 -> ../dm-0 ##下面测试结果出现/mapper实则和/vg0相同[root@station ~]# ll /dev/vg0/lv0 lrwxrwxrwx. 1 root root 7 Apr 22 03:52 /dev/vg0/lv0 -> ../dm-0 测试结果 口令：watch -n 1 'echo ===pvmessage==;pvs;echo===vgmessage===;vgs;echo===lvm message===;lvs;echo ===;df/weixindata' ===pvmessage== PV VG Fmt Attr PSize PFree /dev/vdb1 vg0 lvm2 a-- 1020.00m 720.00m VG #PV #LV #SN Attr VSize VFree vg0 1 1 0 wz--n- 1020.00m 720.00m LV VG Attr LSize Pool Origin Data % Move Log Cpy%Sync Convert lv0 vg0 -wi-ao---- 300.00m === Filesystem 1K-blocks Used Available U se% Mounted on /dev/mapper/vg0-lv0 303788 15520 288268 6% /weixindata ####设备拉伸####[root@station ~]# lvextend -L 900M /dev/vg0/lv0 ##将原设备拉伸为900M Extending logical volume lv0 to 900.00MiB Logical volume lv0 successfullyresized[root@station ~]# xfs_growfs /dev/vg0/lv0 ##文件系统的扩展 meta-data=/dev/mapper/vg0-lv0 isize=256 agcount=4,agsize=19200 blks = sectsz=512 attr=2, projid32bit=1 = crc=0 data = bsize=4096 blocks=76800, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=0 log =internal bsize=4096 blocks=853, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0,rtextents=0 data blocks changed from 76800 to 230400[root@station ~]# lvextend -L 1200M /dev/vg0/lv0 ##继续拉伸为1200 Extending logical volume lv0 to 1.17GiB Insufficient free space: 75 extentsneeded, but only 30 available ///提醒剩余空间不足[root@station ~]# pvcreate /dev/vdb2 ##创建另一个pv Physical volume "/dev/vdb2"successfully created[root@station ~]# vgextend vg0 /dev/vdb2 ##将另一个pv加入vg中 Volume group "vg0"successfully extended[root@station ~]# lvextend -L 1200M /dev/vg0/lv0 ##继续拉伸 Extending logical volume lv0 to 1.17GiB Logical volume lv0 successfully resized//拉伸成功[root@station ~]# xfs_growfs /dev/vg0/lv0 ##文件系统的拉伸 meta-data=/dev/mapper/vg0-lv0 isize=256 agcount=12,agsize=19200 blks = sectsz=512 attr=2, projid32bit=1 = crc=0 data = bsize=4096 blocks=230400, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=0 log =internal bsize=4096 blocks=853, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0,rtextents=0 data blocks changed from 230400 to 307200 ###系统的缩减### 1)缩减之前所做准备[root@station ~]# umount /weixindata/ ##卸载 [root@station ~]# mkfs.ext4 /dev/vg0/lv0 ##更改文件系统 mke2fs 1.42.9 (28-Dec-2013) Filesystem label= OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 76800 inodes, 307200 blocks 15360 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=314572800 10 block groups 32768 blocks per group, 32768 fragments per group 7680 inodes per group Superblock backups stored on blocks: 32768, 98304, 163840, 229376,294912 Allocating group tables: done Writing inode tables: done Creating journal (8192 blocks): done Writing superblocks and filesystem accounting information: done [root@station ~]# mount /dev/vg0/lv0 /weixindata/ ##挂载 [root@station ~]# df ##查看挂载是否成功 Filesystem 1K-blocks Used Available Use% Mounted on /dev/vda1 104739003241020 7232880 31% / devtmpfs 927072 0 927072 0% /dev tmpfs 942660 472 942188 1% /dev/shm tmpfs 942660 17080 925580 2% /run tmpfs 942660 0 942660 0% /sys/fs/cgroup /dev/mapper/vg0-lv0 1176704 3600 1095280 1% /weixindata 2）开始缩减[root@station ~]# umount /weixindata/ ##卸载 [root@station ~]# e2fsck -f /dev/vg0/lv0 ##扫描（系统自己检测文件系统多大） e2fsck 1.42.9 (28-Dec-2013) 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/vg0/lv0: 11/76800 files (0.0% non-contiguous), 13924/307200 blocks[root@station ~]# resize2fs /dev/vg0/lv0 300M ##缩减文件系统为300M resize2fs 1.42.9 (28-Dec-2013) Resizing the filesystem on /dev/vg0/lv0 to 76800 (4k) blocks. The filesystem on /dev/vg0/lv0 is now 76800 blocks long.[root@station ~]# mount /dev/vg0/lv0 /weixindata/ ##挂载 [root@station ~]# lvreduce -L 300 /dev/vg0/lv0 ##缩减设备 WARNING: Reducing active and openlogical volume to 300.00 MiB THIS MAY DESTROY YOUR DATA (filesystemetc.) Do you really want to reduce lv0? [y/n]: y Reducing logical volume lv0 to 300.00MiB Logical volume lv0 successfullyresized[root@station ~]# pvmove /dev/vdb1 /dev/vdb2 ##把设备1信息传给设备2 [root@station ~]# vgreduce vg0 /dev/vdb1 ##把vdb1从vg0移除 Removed "/dev/vdb1" fromvolume group "vg0" /dev/vdb1: Moved: 1.3% /dev/vdb1: Moved: 100.0%[root@station ~]# pvremove /dev/vdb1 把vdb1从pv移除 Labels on physical volume"/dev/vdb1" successfully wiped ####快照####[root@station ~]# touch /weixindata/file{1..10} [root@station ~]# ls /weixindata/ file1 file2 file4 file6 file8 lost+found file10 file3 file5 file7 file9[root@station ~]# umount /weixindata/ [root@station ~]# cd /weixindata/ [root@station weixindata]# ls [root@station weixindata]# cd [root@station ~]# lvcreate -L 50M -nlv0backup -s /dev/vg0/lv0 ###创建快照 Rounding up size to full physicalextent 52.00 MiB Logical volume "lv0backup"created[root@station ~]# mount /dev/vg0/lv0backup /weixindata/ [root@station ~]# cd /weixindata/ [root@station weixindata]# ls file1 file2 file4 file6 file8 lost+found file10 file3 file5 file7 file9[root@station weixindata]# rm -fr * [root@station weixindata]# ls [root@station weixindata]# cd [root@station ~]# umount /weixindata/ [root@station ~]# lvremove /dev/vg0/lvobackup ##删除坏了的快照 One or more specified logical volume(s)not found.[root@station ~]# lvcreate -L 50M -nlv0backup -s /dev/vg0/lv0 ##重新快照 Rounding up size to full physicalextent 52.00 MiB Logical volume "lv0backup"already exists in volume group "vg0"[root@station ~]# mount /dev/vg0/lv0backup /weixindata/ [root@station ~]# ls /weixindata/ file1 file2 file4 file6 file8 lost+found file10 file3 file5 file7 file9 监护口令： watch -n 1 'echo ===pvmessage==; pvs;echo===vgmessage===;vgs;echo===lvmmessage===;lvs;echo ===;df /weixindata' 快照成功时监护界面： ===pvmessage== PV VG Fmt Attr PSize PFree /dev/vdb2 vg0 lvm2 a-- 1020.00m 668.00m VG #PV #LV #SN Attr VSize VFree vg0 1 2 1 wz--n- 1020.00m 668.00m LV VG Attr LSize Pool Origin Data% Move Log Cpy%Sync Convert lv0 vg0 owi-a-s--- 300.00m lv0backup vg0 swi-a-s--- 52.00m lv0 0.00 === Filesystem 1K-blocks Used Available Use% Mounted on /dev/vda1 10473900 3240980 7232920 31% / ####LVM的删除####[root@station ~]# umount /weixindata/ ##卸载 [root@station ~]# lvremove /dev/vg0/lv0backup ##删除快照 Do you really want to remove active logical volume lv0backup? [y/n]: y Logical volume "lv0backup"successfully removed[root@station ~]# lvremove /dev/vg0/lv0 ##删除lv0本身 Do you really want to remove active logical volume lv0? [y/n]: y Logical volume "lv0"successfully removed[root@station ~]# vgremove vg0 删除vg Volume group "vg0"successfully removed[root@station ~]# pvremove /dev/vdb2 删除pv Labels on physical volume"/dev/vdb2" successfully wiped本文转自 AELY木 51CTO博客，原文链接：http://blog.51cto.com/12768057/1919200，如需转载请自行联系原作者