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Ubuntu Extend Disk

After extending the volume in VMware ESXi (shutdown vm, backup/export vm, remove all snapshots, then increased number in disk size, take snapshot of vm again before following the next steps so you can revert mistake/error).

The following example is extending volume on root partition on a system that is already using LVM.

  1. ssh into the system, switch to root and run cfdisk
    # cfdisk
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  13. After exiting cfdisk 
     # fdisk -l /dev/sda 
 Disk /dev/sda: 20 GiB, 21474836480 bytes, 41943040 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
 Disklabel type: dos
 Disk identifier: 0xc8b647ff

 Device     Boot    Start      End  Sectors  Size Id Type
 /dev/sda1  *        2048   999423   997376  487M 83 Linux
 /dev/sda2        1001470 16775167 15773698  7.5G  5 Extended
 /dev/sda3       16775168 41943039 25167872   12G 8e Linux LVM (***** See new partition /dev/sda3*****)
 /dev/sda5        1001472 16775167 15773696  7.5G 8e Linux LVM
  14. Reboot system before next step (or else you might get Device
    /dev/sda3 not found (or ignored by filtering)    )

     # shutdown now -r
  15. Initialize the new volume 
     # pvcreate /dev/sda3
   Physical volume "/dev/sda3" successfully created
  16. Get the name of volume to extend 
     # vgdisplay
   --- Volume group ---
   VG Name               linuxetc1-vg (***** this is vg i'm extending*****)
   System ID             
   Format                lvm2
   Metadata Areas        1
   Metadata Sequence No  3
   VG Access             read/write
   VG Status             resizable
   MAX LV                0
   Cur LV                2
   Open LV               2
   Max PV                0
   Cur PV                1
   Act PV                1
   VG Size               7.52 GiB
   PE Size               4.00 MiB
   Total PE              1925
   Alloc PE / Size       1925 / 7.52 GiB
   Free  PE / Size       0 / 0  
   ...
  17. Extend volume group 
     # vgextend linuxetc1-vg /dev/sda3
   Volume group "linuxetc1-vg" successfully extended
  18. Extend root 
     # lvextend -l+100%FREE /dev/linuxetc1-vg/root
   Size of logical volume linuxetc1-vg/root changed from 6.52 GiB (1669 extents) to 18.52 GiB (4741 extents).
   Logical volume root successfully resized.


 Or if you only wanted to give 5 more GB to root
 # lvextend -L +5g /dev/linuxetc1-vg/root
  19. Get filesystem name for next step 
     # df -h
 Filesystem                      Size  Used Avail Use% Mounted on
 udev                            477M     0  477M   0% /dev
 tmpfs                           100M  4.6M   95M   5% /run
 /dev/mapper/linuxetc1--vg-root  6.3G  2.5G  3.5G  42% /            (***** this line*****)
 tmpfs                           497M     0  497M   0% /dev/shm
 tmpfs                           5.0M     0  5.0M   0% /run/lock
 tmpfs                           497M     0  497M   0% /sys/fs/cgroup
 /dev/sda1                       472M  105M  343M  24% /boot
 tmpfs                           100M     0  100M   0% /run/user/1000
  20. Extend filesystem 
     # resize2fs /dev/mapper/linuxetc1--vg-root
 resize2fs 1.42.13 (17-May-2015)
 Filesystem at /dev/mapper/linuxetc1--vg-root is mounted on /; on-line resizing required
 old_desc_blocks = 1, new_desc_blocks = 2
 The filesystem on /dev/mapper/linuxetc1--vg-root is now 4854784 (4k) blocks long.
  21. See the increased size 
     # df -h
 Filesystem                      Size  Used Avail Use% Mounted on
 udev                            477M     0  477M   0% /dev
 tmpfs                           100M  4.6M   95M   5% /run
 /dev/mapper/linuxetc1--vg-root   19G  2.5G   15G  15% /         (***** this line*****)
 tmpfs                           497M     0  497M   0% /dev/shm
 tmpfs                           5.0M     0  5.0M   0% /run/lock
 tmpfs                           497M     0  497M   0% /sys/fs/cgroup
 /dev/sda1                       472M  105M  343M  24% /boot
 tmpfs                           100M     0  100M   0% /run/user/1000

2. Faster Method Tested in Ubuntu Server 18.04.3 LTS

This method is a little faster than the first. This is due to a new option in the cfdisk menu called “Resize” that saves some steps.

After extending the volume in VMware ESXi (shutdown vm, backup/export vm, remove all snapshots, then increased number in disk size, take snapshot of vm again before following the next steps so you can revert mistake/error).

The following example is extending volume on root partition on a system that is already using LVM.

  1. ssh into the system, switch to root and run cfdisk.
  2. Choose the partition to extend and select “Resize”. enter image description here
  3. Set the “New size”. enter image description here
  4. After pressing enter, you’ll see screen with the following note “Partition [someNumber] resized”: enter image description here
  5. Next you’ll need to “Write” (save) your changes: enter image description here enter image description here enter image description here
  6. Quit cfdisk. When you exit you may see message “syncing disks”. enter image description here enter image description here
  7. I rebooted my system at this point but it may not be necessary. Now you can pickup from step 19 from the first method (repeated below).
  8. (19) Get filesystem name for next step 
     # df -h
 Filesystem                      Size  Used Avail Use% Mounted on
 udev                            477M     0  477M   0% /dev
 tmpfs                           100M  4.6M   95M   5% /run
 /dev/mapper/linuxetc1--vg-root  6.3G  2.5G  3.5G  42% /            (***** this line*****)
 tmpfs                           497M     0  497M   0% /dev/shm
 tmpfs                           5.0M     0  5.0M   0% /run/lock
 tmpfs                           497M     0  497M   0% /sys/fs/cgroup
 /dev/sda1                       472M  105M  343M  24% /boot
 tmpfs                           100M     0  100M   0% /run/user/1000
  9. (20) Extend filesystem 
     # resize2fs /dev/mapper/linuxetc1--vg-root
 resize2fs 1.42.13 (17-May-2015)
 Filesystem at /dev/mapper/linuxetc1--vg-root is mounted on /; on-line resizing required
 old_desc_blocks = 1, new_desc_blocks = 2
 The filesystem on /dev/mapper/linuxetc1--vg-root is now 4854784 (4k) blocks long.
  10. (21) See the increased size 
     # df -h
 Filesystem                      Size  Used Avail Use% Mounted on
 udev                            477M     0  477M   0% /dev
 tmpfs                           100M  4.6M   95M   5% /run
 /dev/mapper/linuxetc1--vg-root   19G  2.5G   15G  15% /         (***** this line*****)
 tmpfs                           497M     0  497M   0% /dev/shm
 tmpfs                           5.0M     0  5.0M   0% /run/lock
 tmpfs                           497M     0  497M   0% /sys/fs/cgroup
 /dev/sda1                       472M  105M  343M  24% /boot
 tmpfs                           100M     0  100M   0% /run/user/1000

Articles:
https://wiki.ubuntu.com/Lvm
http://www.geoffstratton.com/expand-hard-disk-ubuntu-lvm

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