Extend CentOS 6/7 Disks in VMWare

Humboldt Penguins of the Ballestas Islands; photo by Ryan Murphy.

I’ve always felt there weren’t enough straight forward guides on how to do this. This is an example of how to (relatively) quickly resize & extend a disk on CentOS 6/7. This is used when increasing the size of a disk in a virtual machine, in this example I’ll use VMWare.

Important

• Make sure you have a good backup of your data

• This guide assumes you’re using CentOS 6.x or CentOS 7.x

• This guide assumes you’re using vCenter 5+, although the process in CentOS should still stay the same in other environments

1) Power off the VM

2) Add disk space directly on the VM.

• VM Properties -> Hard Disk -> Disk Provisioning -> Provisioned Size

3) Download and mount the gParted ISO (Available Here)

• Ensure the VM is set to boot to BIOS, so you can configure the boot order, CD/DVD should be first. (VM Properties -> Options -> Boot Options -> Boot to BIOS)

• You can mount the ISO from a datastore, or use the console by clicking the CD/Wrench Icon and selecting “Connect to ISO on Local Disk…”

4) Boot into gParted and resize the volume. You can select the default values for all prompts.

• Click the disk, select resize

• Change the ‘New Size’ to be the new size of the disk, click resize.

• Click the disk, click apply/apply. (Note: If there are errors in gParted you should always read/investigate)

• When complete, right click the previously locked drive(s) and click “Activate” then close.

• Edit VM settings to boot into BIOS on next reboot

• Shutdown the machine and boot back into BIOS, you’ll want to ensure the Hard Disk is first in the boot order

5) Boot into CentOS

6) It’s recommended you create a snapshot at this point, as if things go wrong it will be hard to recover.

7) If there’s a volume group, you may need to remove any missing volume group references.

• Check volume groups

sudo vgs

• Remove all missing physical volumes from the volume group

sudo vgreduce --removemissing

8) Find the physical volume you want to resize

sudo pvdisplay

9) Resize (expand) your physical volume.

sudo lvm pvresize -v PHYSICAL_VOLUME

10) Find the logical volume you want to expand

sudo df -h

11) Resize your logical volume and expand the file system to fit.

• For CentOS 7 and below

sudo lvextend -l +100%FREE LOGICAL_VOLUME
sudo resize2fs FILESYSTEM

• CentOS 7+ uses the XFS filesystem, therefore you should use xfsprogs

sudo yum –y install xfsprogs.x86_64
sudo xfs_growfs FILESYSTEM

12) Use df -h and fdisk -l to check disk usage and verify everything looks good