阿里云盘扩容（SUSE Linux下）

系统基于LVM卷组管理

1、在阿里云购买磁盘扩容后，系统重启

2、重启后lv状态不可用，无法挂在lvm

mount /dev/mapper/vgdisk-app /home
mount: special device /dev/mapper/vgdisk-app does not exist

查看lv状态

  --- Logical volume ---
  LV Name                /dev/vgdisk/app
  VG Name                vgdisk
  LV UUID                j9GvOW-sivU-18Nq-3vfN-cmTU-49Je-nvu7rK
  LV Write Access        read/write
  LV Creation host, time iZ94jg74t5xZ, 2015-08-27 19:39:19 +0800
  LV Status              NOT available
  LV Size                100.00 GiB
  Current LE             25600
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
   
  --- Logical volume ---
  LV Name                /dev/vgdisk/data
  VG Name                vgdisk
  LV UUID                Y3F520-hGF2-sazF-C1Ch-kbWl-X4LE-XAta3i
  LV Write Access        read/write
  LV Creation host, time iZ94jg74t5xZ, 2015-08-27 19:41:34 +0800
  LV Status              NOT available
  LV Size                350.00 GiB
  Current LE             89600
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto

为啥状态不正确了呢，应该扩容导致的问题，找阿里云官方资料，要么是Window下，要么是linux非LVM管理的，感觉按照官方操作不靠谱。

遂自行查找基于LVM卷管理的磁盘扩容资料，找到了一些比较全面的参考资料，结合阿里云环境把问题解决了。

SUSE10 LVM实现扩展PV操作指导书

需要对lvm中的管理信息重新扫描，文档中介绍了很多命令，实际上对于扩容至需要更新pv信息，vg信息

处理方法：

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step 1：扫描和扩容PV

iZ94jg74t5xZ:~ # pvscan
  PV /dev/xvdc   VG vgdisk   lvm2 [500.00 GiB / 50.00 GiB free]
  Total: 1 [500.00 GiB] / in use: 1 [500.00 GiB] / in no VG: 0 [0   ]
iZ94jg74t5xZ:~ # pvresize /dev/xvdc
  Physical volume "/dev/xvdc" changed
  1 physical volume(s) resized / 0 physical volume(s) not resized

step 2：更新VG信息

iZ94jg74t5xZ:~ # vgchange -ay
  2 logical volume(s) in volume group "vgdisk" now active

更新完成后查看vg信息和lv状态，一切正常

iZ94jg74t5xZ:~ # vgdisplay 
  --- Volume group ---
  VG Name               vgdisk
  System ID             
  Format                lvm2
  Metadata Areas        1
  Metadata Sequence No  4
  VG Access             read/write
  VG Status             resizable
  MAX LV                0
  Cur LV                2
  Open LV               0
  Max PV                0
  Cur PV                1
  Act PV                1
  VG Size               1000.00 GiB
  PE Size               4.00 MiB
  Total PE              255999
  Alloc PE / Size       115200 / 450.00 GiB
  Free  PE / Size       140799 / 550.00 GiB
  VG UUID               IcVDC2-UAKv-2Cbm-iE8c-JYjp-tupP-TXxuTC
   
iZ94jg74t5xZ:~ # lvdisplay 
  --- Logical volume ---
  LV Name                /dev/vgdisk/app
  VG Name                vgdisk
  LV UUID                j9GvOW-sivU-18Nq-3vfN-cmTU-49Je-nvu7rK
  LV Write Access        read/write
  LV Creation host, time iZ94jg74t5xZ, 2015-08-27 19:39:19 +0800
  LV Status              available
  # open                 0
  LV Size                100.00 GiB
  Current LE             25600
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     1024
  Block device           252:0
   
  --- Logical volume ---
  LV Name                /dev/vgdisk/data
  VG Name                vgdisk
  LV UUID                Y3F520-hGF2-sazF-C1Ch-kbWl-X4LE-XAta3i
  LV Write Access        read/write
  LV Creation host, time iZ94jg74t5xZ, 2015-08-27 19:41:34 +0800
  LV Status              available
  # open                 0
  LV Size                350.00 GiB
  Current LE             89600
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     1024
  Block device           252:1

step 3:扩展LV

iZ94jg74t5xZ:/home #  lvextend -L +400G /dev/vgdisk/data
  Extending logical volume data to 750.00 GiB
  Logical volume data successfully resized

step 4：扩展文件系统

iZ94jg74t5xZ:~ # resize2fs /dev/vgdisk/data
resize2fs 1.41.9 (22-Aug-2009)
resize2fs: Bad magic number in super-block while trying to open /dev/vgdisk/data
Couldn't find valid filesystem superblock.

（插曲：由于本人使用的是XFS文件系统，所以使用resize2fs时，失败了。联想到文件系统的差异性，尝试使用了xfs文件系统的扩展命令，最终完成扩展）

针对XFS文件系统的容量扩展

iZ94jg74t5xZ:~ # xfs_growfs /dev/vgdisk/data
meta-data=/dev/mapper/vgdisk-data isize=256    agcount=4, agsize=22937600 blks
         =                       sectsz=512   attr=2
data     =                       bsize=4096   blocks=91750400, imaxpct=25
         =                       sunit=0      swidth=0 blks
naming   =version 2              bsize=4096   ascii-ci=0
log      =internal               bsize=4096   blocks=44800, version=2
         =                       sectsz=512   sunit=0 blks, lazy-count=1
realtime =none                   extsz=4096   blocks=0, rtextents=0
data blocks changed from 91750400 to 196608000

最后mount文件系统，完成任务

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从上面操作可以看出基于LVM管理磁盘优势太明显了，比阿里官方的操作方式简单安全得多