Resize Azure Linux CentOS 7 VM OS Disk

 In this blog post, I will show you how I increase the size of my Linux CentOS Azure VM OS disk size.

By default, Azure Linux VM comes with a 30GB Operating System (OS) disk size.

Step 1 – Stop VM

My first step will be stopping the VM and increasing the disk space.

Step 2 – Increase OS disk space

To increase the disk space of my OS disk, I will click on Disks and click on the OS disk.

I will increase it from 30GB to 35GB.

Step 3 – Start VM

After the resize is completed I will restart the VM.

Step 4 -Connect using SSH and Check size before the change

I will connect to the VM using SSH and use the following command to check the current size.

df -h

As you can see I am using 30G partition for (/dev/sda2)

Note: To check the size of the off all the disks and partitions on the VM I run:

sblk

Azure CentOS VMs are using /dev/sda disk by default with 2 partitions /dev/sda and /dev/sda2.

The OS partition sits on /dev/sda2 and this is the partition I’m going to resize.

Step 5 – Check partitions on Disk

To check all the partitions on the dev/sda I will run the following command.

fdisk -l /dev/sda

In my case, I need to increase the 2nd partition (sda2)

Now, I will use the fdisk utility to delete the sda2 partition and create a new one with a larger size.

Note: No data will be lost.

I will run the following command to work with the /dev/sda disk.

fdisk /dev/sda

I will type p

p

Next, I will type d to delete the 2nd partition (/dev/sda2)

d

Now, I will type n and create a new partition with a larger size.

n

From the two option, I will type p for new primary partition.

p

For the first cylinder, I can type a value or use the default which is 64.

Note: the value (64) is shown in the 3rd screenshots above.

I will type w to write the changes

w

I will restart the VM using

sudo reboot

Step 6 – resize

After the VM is up, I will ssh to it and run the following command.

xfs_growfs /

To check the new size, I will type.

df -h

To view all the disk and partitions after the change I will type.

lsblk