Adicionar um novo disco ao LVM

Colaboração: Renato Rudnicki

Data de Publicação: 04 de abril de 2012

Caso seu LVM esteja sem espaço para expandir partições, uma solução é adicionar outro disco ao Volume Group e então expandir a partição desejada.

Espaço em disco atual:

  [root@bacula log]# df -h
  Filesystem            Size  Used Avail Use% Mounted on
  /dev/mapper/VolGroup00-LogVol00    3.9G  3.6G   99M  98% /
  /dev/xvda1                                99M   14M   81M  15% /boot
  tmpfs                             1.0G     0  1.0G   0% /dev/shm
  10.0.2.244:/DataVolume/backup      1.8T  1.6T  267G  86% /backup

1. Particionar o disco como lvm (8e)

2. Listar os volume groups existentes

     [root@bacula log]# vgdisplay -s
     "VolGroup00" 7.88 GB   [7.88 GB   used / 0    free]
   

3. Listar os logical volumes e verificar qual é o que será modificado

     [root@bacula log]# lvdisplay
     --- Logical volume ---
     LV Name                /dev/VolGroup00/LogVol00
     VG Name                VolGroup00
     LV UUID                ihlQed-fJQ9-ysfa-naJR-Nzzg-q9Qn-47c3EO
     LV Write Access        read/write
     LV Status              available
     # open                 1
     LV Size                4.00 GB
     Current LE             128
     Segments               1
     Allocation             inherit
     Read ahead sectors     auto
     - currently set to     256
     Block device           253:0
     
     --- Logical volume ---
     LV Name                /dev/VolGroup00/LogVol01
     VG Name                VolGroup00
     LV UUID                8SvsWD-mRMp-LRLe-zecX-cdGF-EZ6G-FO1lsp
     LV Write Access        read/write
     LV Status              available
     # open                 1
     LV Size                3.88 GB
     Current LE             124
     Segments               1
     Allocation             inherit
     Read ahead sectors     auto
     - currently set to     256
     Block device           253:1
   

4. Criar um novo physical volume com o disco adicionado anteriormente

     # pvcreate /dev/xvdb1
     Physical volume "/dev/xvdb1" successfully created
   

5. Adicionar o disco ao Volume Group desejado

     vgextend VolGroup00 /dev/xvdb1
   

6. Listar o phisical volume (pvdisplay -s)

     [root@bacula log]# pvdisplay -s
     Device "/dev/xvda2" has a capacity of 0
     Device "/dev/xvdb1" has a capacity of 8.00 GB
   

7. Adicionar o novo disco ao volume group escolhido

     [root@bacula log]# vgextend VolGroup00 /dev/xvdb1
     Volume group "VolGroup00" successfully extended
   

   Repare no campo Free PE / Size , existe 8GB livres que corresponde ao novo disco adicionado.

8. Extender o volume

     [root@bacula log]# lvextend -L +7.9G /dev/VolGroup00/LogVol00
     Extending logical volume LogVol00 to 11.00 GB
     Logical volume LogVol00 successfully resized
   

9. Atualizar o espaço da partição extendida

     [root@bacula log]# resize2fs /dev/VolGroup00/LogVol00
     resize2fs 1.39 (29-May-2006)
     Filesystem at /dev/VolGroup00/LogVol00 is mounted on /; on-line resizing required
     Performing an on-line resize of /dev/VolGroup00/LogVol00 to 2883584 (4k) blocks.
     The filesystem on /dev/VolGroup00/LogVol00 is now 2883584 blocks long.
   

10. Verifique se o espaço em disco está com o novo tamanho:

      [root@bacula log]# df -h
      Filesystem            Size  Used Avail Use% Mounted on
      /dev/mapper/VolGroup00-LogVol00  11G  3.6G  6.6G  36% /
      /dev/xvda1                      99M   14M   81M  15% /boot
      tmpfs                           1.0G     0  1.0G   0% /dev/shm
      10.0.2.244:/DataVolume/backup   1.8T  1.6T  267G  86% /backup
    

    Informações retiradas daqui: http://www.fogonacaixadagua.com.br/2009/02/adicionando-um-novo-disco-a-um-volume-lvm2-online/ e manpage

Observação

Caso tenha expandido o Logical Volume errado, você pode corrigir isso usando o lvreduce:

  [root@bacula log]# lvreduce -L -7.8G /dev/VolGroup00/LogVol01
  Rounding up size to full physical extent 7.8 GB
  WARNING: Reducing active and open logical volume to 3.91 GB
  THIS MAY DESTROY YOUR DATA (filesystem etc.)
  Do you really want to reduce LogVol01? [y/n]: y
  Reducing logical volume LogVol01 to 3.91 GB
  Logical volume LogVol01 successfully resized