LVM Expansion/Extend the File System in Linux

LVM Expansion/Extend the File System in Linux

Note:   Current Size of VG (Volume Group) DISKVG08907 is 59.99G & we have to extend upto 80G

There are two methods to expand file system online in Linux: (recommended on LVM Version 2)

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#lvm version  (command to check LVM Version)

#lvextend -L 79.99G /dev/DISKVG08907/app         (do not mention any sign while rounding up)

(Above command will round up the logical volume app to 79.99 GB)

#resize2fs /dev/DISKVG08907/app                         

(Above command will resize the logical volume app)

Or

#lvextend -L +20G /dev/DISKVG08907/app           (please remember to mention + sign while adding)

(Above command will add 20GB more in logical volume app)

#resize2fs /dev/DISKVG08907/app

(Above command will resize the logical volume app)

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Below is the example to extend file system online

bash-3.2# hostname

LinuxServer1

(Status before expanding /app file system)

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bash-3.2# df –HT  /app

Filesystem                                           Type     Size   Used  Avail Use% Mounted on

/dev/mapper/DISKVG08907-app     ext3      64G   461M    60G   1% /app

bash-3.2# fdisk -l

Disk /dev/sda: 16.1 GB, 16106127360 bytes

255 heads, 63 sectors/track, 1958 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *           1          33      265041   83  Linux

/dev/sda2              34        1958    15462562+  8e  Linux LVM

Disk /dev/sdb: 85.8 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               1        7832    62910508+  8e  Linux LVM

bash-3.2#

bash-3.2# pvs

  PV                  VG                   Fmt      Attr      PSize                PFree

  /dev/sdb1    DISKVG08907             lvm2    a-          59.99G                       0

bash-3.2# vgs

  VG        #PV #LV #SN Attr   VSize  VFree

  DISKVG08907   1   1   0 wz--n- 59.99G    0

bash-3.2# lvs

  LV      VG                               Attr      LSize   Origin Snap%  Move Log Copy%  Convert

  app     DISKVG08907            -wi-ao  59.99G

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bash-3.2# fdisk /dev/sdb

The number of cylinders for this disk is set to 10443.

There is nothing wrong with that, but this is larger than 1024,

and could in certain setups cause problems with:

1) software that runs at boot time (e.g., old versions of LILO)

2) booting and partitioning software from other OSs

   (e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): p

Disk /dev/sdb: 85.8 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               1        7832    62910508+  8e  Linux LVM

Command (m for help): n

Command action

   e   extended

   p   primary partition (1-4)

p

Partition number (1-4): 2

First cylinder (7833-10443, default 7833): (press enter)

Using default value 7833

Last cylinder or +size or +sizeM or +sizeK (7833-10443, default 10443): (press enter)

Using default value 10443

Command (m for help): p

Disk /dev/sdb: 85.8 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               1        7832    62910508+  8e  Linux LVM

/dev/sdb2            7833       10443    20972857+  83  Linux

Command (m for help): t

Partition number (1-4): 2

Hex code (type L to list codes): 8e

Changed system type of partition 2 to 8e (Linux LVM)

Command (m for help): p

Disk /dev/sdb: 85.8 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               1        7832    62910508+  8e  Linux LVM

/dev/sdb2            7833       10443    20972857+  8e  Linux LVM

Command (m for help): w

The partition table has been altered!

Calling ioctl() to re-read partition table.

WARNING: Re-reading the partition table failed with error 16: Device or resource busy.

The kernel still uses the old table.

The new table will be used at the next reboot.

Syncing disks.

bash-3.2# partprobe /dev/sdb       

(Partprobe is a program that informs the operating system kernel of partition table changes, by requesting that the operating system re-read the partition table)

bash-3.2# fdisk -l

Disk /dev/sda: 16.1 GB, 16106127360 bytes

255 heads, 63 sectors/track, 1958 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sda1   *           1          33      265041   83  Linux

/dev/sda2              34        1958    15462562+  8e  Linux LVM

Disk /dev/sdb: 85.8 GB, 85899345920 bytes

255 heads, 63 sectors/track, 10443 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1               1        7832    62910508+  8e  Linux LVM

/dev/sdb2            7833       10443    20972857+  8e  Linux LVM

bash-3.2# pvcreate /dev/sdb2

  Physical volume "/dev/sdb2" successfully created

bash-3.2# pvs

  PV         VG           Fmt  Attr PSize  PFree

  /dev/sda2  vg00         lvm2 a-   14.62G  5.88G

  /dev/sdb1  DISKVG08907 lvm2 a-   59.99G     0

  /dev/sdb2               lvm2 a-   20.00G 20.00G

bash-3.2# vgs

  VG           #PV #LV #SN Attr   VSize  VFree

  DISKVG08907   1   1   0 wz--n- 59.99G    0

  vg00           1   5   0 wz--n- 14.62G 5.88G

bash-3.2# vgextend -v DISKVG08907 /dev/sdb2

    Checking for volume group "DISKVG08907"

    Archiving volume group "DISKVG08907" metadata (seqno 2).

    Wiping cache of LVM-capable devices

    Adding physical volume '/dev/sdb2' to volume group 'DISKVG08907'

    Volume group "DISKVG08907" will be extended by 1 new physical volumes

    Creating volume group backup "/etc/lvm/backup/DISKVG08907" (seqno 3).

  Volume group "DISKVG08907" successfully extended

bash-3.2# lvextend -L 79.99G /dev/DISKVG08907/app

  Rounding up size to full physical extent 79.99 GB

  Extending logical volume app to 79.99 GB

  Logical volume app successfully resized

bash-3.2# resize2fs /dev/DISKVG08907/app

resize2fs 1.39 (29-May-2006)

Filesystem at /dev/DISKVG08907/app is mounted on /app; on-line resizing required

Performing an on-line resize of /dev/DISKVG08907/app to 20969472 (4k) blocks.

The filesystem on /dev/DISKVG08907/app is now 20969472 blocks long.

(Status after expanding /app file system)

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bash-3.2# df –HT /app

Filesystem                                           Type     Size   Used Avail   Use% Mounted on

/dev/mapper/DISKVG08907-app     ext3      85G   465M    80G   1%   /app

bash-3.2# pvs

  PV         VG           Fmt  Attr PSize  PFree

  /dev/sda2  vg00         lvm2 a-   14.62G  5.88G

  /dev/sdb1  DISKVG08907 lvm2 a-   59.99G     0

  /dev/sdb2  DISKVG08907 lvm2 a-   20.00G 20.00G

bash-3.2# vgs

  VG           #PV #LV #SN Attr   VSize  VFree

  DISKVG08907   2   1   0 wz--n- 79.99G 20.00G

bash-3.2# lvs

  LV      VG           Attr   LSize   Origin Snap%  Move Log Copy%  Convert

  app     DISKVG08907 -wi-ao  79.99G

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bash-3.2# cd /app     

bash-3.2# du -sh *                 (check & confirm /app data)

16K     lost+found

259M    file1

bash-3.2# cat /etc/fstab         (check entry in /etc/fstab for /app file system)

/dev/DISKVG08907/app   /app                    ext3    defaults        0 0

Created by: Yogesh Anuvadia