Posted inGoodies Goodies | Linux

Extend LVM with extra disk

Find the LVM details of the volume group that you want to add a disk to:

sudo lvdisplay

Example output, The two with bold are the needed information in this example

root@packetfence02:~# sudo lvdisplay
  --- Logical volume ---
  LV Path                /dev/packetfence02-vg/root
  LV Name                root
  VG Name                packetfence02-vg
  LV UUID                g5B36c-Yb10-sfmL-IjcI-0Z3E-iHup-EkS0oU
  LV Write Access        read/write
  LV Creation host, time packetfence02, 2024-06-07 22:38:36 +0200
  LV Status              available
  # open                 1
  LV Size                <248.55 GiB
  Current LE             63628
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           254:0

  --- Logical volume ---
  LV Path                /dev/packetfence02-vg/swap_1
  LV Name                swap_1
  VG Name                packetfence02-vg
  LV UUID                X2A1xo-bWvK-0eei-322I-6QAU-KdhL-NVRjuz
  LV Write Access        read/write
  LV Creation host, time packetfence02, 2024-06-07 22:38:36 +0200
  LV Status              available
  # open                 2
  LV Size                976.00 MiB
  Current LE             244
  Segments               1
  Allocation             inherit
  Read ahead sectors     auto
  - currently set to     256
  Block device           254:1

Find more info about the new disk

sudo fdisk -l

Example output, the text with bold are the new disk path:

root@packetfence02:~# sudo fdisk -l


Disk /dev/sda: 250 GiB, 268435456000 bytes, 524288000 sectors
Disk model: QEMU HARDDISK
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x878d4176

Device     Boot   Start       End   Sectors   Size Id Type
/dev/sda1  *       2048    999423    997376   487M 83 Linux
/dev/sda2       1001470 524285951 523284482 249.5G  5 Extended
/dev/sda5       1001472 524285951 523284480 249.5G 8e Linux LVM


Disk /dev/mapper/packetfence02--vg-root: 248.55 GiB, 266875174912 bytes, 521240576 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/mapper/packetfence02--vg-swap_1: 976 MiB, 1023410176 bytes, 1998848 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes


Disk /dev/sdb: 250 GiB, 268435456000 bytes, 524288000 sectors
Disk model: QEMU HARDDISK
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

Create the new disk

sudo pvcreate /dev/sdb
  Physical volume "/dev/sdb" successfully created.

Add newly created pv named /dev/sdb to an existing lv packetfence02-vg

sudo vgextend packetfence02-vg /dev/sdb
  Volume group "packetfence02-vg" successfully extended

Extend the volume group with all available disk space

sudo lvm lvextend -l +100%FREE /dev/packetfence02-vg/root
  Size of logical volume packetfence02-vg/root changed from <248.55 GiB (63628 extents) to 498.56 GiB (127632 extents).
  Logical volume packetfence02-vg/root successfully resized.

Resize volume

sudo resize2fs -p /dev/packetfence02-vg/root
   resize2fs 1.46.2 (28-Feb-2021)
   Filesystem at /dev/packetfence02-vg/root is mounted on /; on-line resizing required
   old_desc_blocks = 32, new_desc_blocks = 63
   The filesystem on /dev/packetfence02-vg/root is now 130695168 (4k) blocks long.

Validate result with df

sudo df -H
   root@packetfence02:~# df -H
   Filesystem                          Size  Used Avail Use% Mounted on
   udev                                8.4G     0  8.4G   0% /dev
   tmpfs                               1.7G  2.2M  1.7G   1% /run
   /dev/mapper/packetfence02--vg-root  526G   23G  480G   5% /
   .....

For other filesystems

The resize2fs command is the standard and most reliable tool for resizing ext{2,3,4} filesystems. Are you using different filesystem? Try the following tools:

  1. btrfs filesystem resize Use this command to grow or shrink Btrfs filesystems online.
  2. xfs_growfs : Use for resizing XFS filesystems. It can only grow filesystems and works online.