LVM

[Guest]

LVM Concept

Logical Volume Group



Logical Volumes

Code: Select all

# lvmdiskscan
  /dev/hda  [        9.54 GB]
  /dev/hda1 [      101.94 MB]
  /dev/hda2 [        7.94 GB]
  /dev/hda3 [        1.49 GB]
  /dev/hdb  [        3.02 GB]
  /dev/hdd  [        7.87 GB]
  /dev/hdd1 [        1.00 GB]
  /dev/hdd2 [        6.86 GB]
  3 disks
  5 partitions
  0 LVM physical volume whole disks
  0 LVM physical volumes


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# pvcreate /dev/hdb /dev/hdd
  No physical volume label read from /dev/hdb
  Physical volume "/dev/hdb" successfully created
  No physical volume label read from /dev/hdd
  Physical volume "/dev/hdd" successfully created


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# vgcreate data_lvm /dev/hdb /dev/hdd
  Volume group "data_lvm" successfully created


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# vgdisplay
  --- Volume group ---
  VG Name               data_lvm
  System ID
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  1
  VG Access             read/write
  VG Status             resizable
  MAX LV                255
  Cur LV                0
  Open LV               0
  Max PV                255
  Cur PV                2
  Act PV                2
  VG Size               10.89 GB
  PE Size               4.00 MB
  Total PE              2788
  Alloc PE / Size       0 / 0
  Free  PE / Size       2788 / 10.89 GB
  VG UUID               uJaZGq-ri8h-inuU-Lxp7-Z1rj-PqLs-Hlz1Ge


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# vgchange -ay data_lvm
  1 logical volume(s) in volume group "data_lvm" now active


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# lvcreate -L2G -ndatavol1 data_lvm
  Logical volume "datavol1" created


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# mkfs.ext3 /dev/data_lvm/datavol1
mke2fs 1.35 (28-Feb-2004)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
262144 inodes, 524288 blocks
26214 blocks (5.00%) reserved for the super user
First data block=0
16 block groups
32768 blocks per group, 32768 fragments per group
16384 inodes per group
Superblock backups stored on blocks:
        32768, 98304, 163840, 229376, 294912

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.


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[Guest]

To increase LVM Size

Code: Select all

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/volgroup-datavol1
                      5.0G   33M  4.7G   1% /data


# lvmdiskscan
  /dev/hda  [        9.54 GB]
  /dev/hda1 [      101.94 MB]
  /dev/hda2 [        7.94 GB]
  /dev/hda3 [        1.49 GB]
  /dev/hdb  [        3.02 GB] LVM physical volume
  /dev/hdd  [        7.87 GB] LVM physical volume
  1 disk
  3 partitions
  2 LVM physical volume whole disks
  0 LVM physical volumes


# vgdisplay
  --- Volume group ---
  VG Name               volgroup
  System ID
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  3
  VG Access             read/write
  VG Status             resizable
  MAX LV                255
  Cur LV                1
  Open LV               0
  Max PV                255
  Cur PV                2
  Act PV                2
  VG Size               10.89 GB
  PE Size               4.00 MB
  Total PE              2788
  Alloc PE / Size       1282 / 5.01 GB
  Free  PE / Size       1506 / 5.88 GB
  VG UUID               Y5DfF5-yIij-m73d-P083-DAjx-fHeu-6nVPzh


# lvextend -L+5.88G /dev/volgroup/datavol1
  Rounding up size to full physical extent 5.88 GB
  Extending logical volume datavol1 to 10.89 GB
  Logical volume datavol1 successfully resized



# e2fsck -f /dev/volgroup/datavol1
e2fsck 1.35 (28-Feb-2004)
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/volgroup/datavol1: 12/671744 files (0.0% non-contiguous), 29298/1312768 blocks


# resize2fs /dev/volgroup/datavol1
resize2fs 1.35 (28-Feb-2004)
Resizing the filesystem on /dev/volgroup/datavol1 to 2854912 (4k) blocks.
The filesystem on /dev/volgroup/datavol1 is now 2854912 blocks long.

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/volgroup-datavol1
                       11G   33M   11G   1% /data

# vgdisplay
  --- Volume group ---
  VG Name               volgroup
  System ID
  Format                lvm2
  Metadata Areas        2
  Metadata Sequence No  4
  VG Access             read/write
  VG Status             resizable
  MAX LV                255
  Cur LV                1
  Open LV               1
  Max PV                255
  Cur PV                2
  Act PV                2
  VG Size               10.89 GB
  PE Size               4.00 MB
  Total PE              2788
  Alloc PE / Size       2788 / 10.89 GB
  Free  PE / Size       0 / 0
  VG UUID               Y5DfF5-yIij-m73d-P083-DAjx-fHeu-6nVPzh