[Create the AWS Elastic Block Store (EBS) volume in the same region as same as the cluster. If have the AWS cli/console.]
$ aws ec2 create-volume --availability-zone=eu-west-1a --size=10 --volume-type=gp2

[With this new volume, attach it onto the master node in cluster.]
$ aws ec2 attach-volume --device /dev/xvdf --instance-id <MASTER NODE ID> --volume-id <YOUR VOLUME ID>

[In the master node, check to see if device is attached to instance by running lsblk. If the last step worked should see volume at the bottom of the list.]
$ lsblk
NAME        MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
loop0         7:0    0 17.9M  1 loop /snap/amazon-ssm-agent/1068
loop1         7:1    0 89.3M  1 loop /snap/core/6673
nvme0n1     259:0    0   25G  0 disk
└─nvme0n1p1 259:1    0   25G  0 part /
nvme1n1     259:2    0   10G  0 disk

[With the name of the volume, create the filesystem on the volume.]
$ sudo mkfs -t xfs /dev/<NAME OF VOLUME FROM PREV STEP>
