The existing disk capacity may be insufficient to support the increasing number of containers or images on a node in a Kubernetes cluster. You can attach one or more data disks to the node. In this case, you must expand the disk capacity to provide more storage space for containers and images. This topic describes how to mount a data disk to a node.
Prerequisites
Mount a data disk
You can use one of the following methods to expand the disk capacity of an existing
node:
- If no disk is attached to the node, attach a data disk to the node. For more information, see Mount a disk to the Docker data directory.
- If you have purchased a data disk for the node, but the disk fails to be attached to the node, perform the following steps:
Note
- To minimize the potential risks, we recommend that you create snapshots or backups of the node.
- Make sure that the applications deployed on the node can be scheduled to other nodes in the cluster.
- Perform the steps during off-peak hours.
- If you drain the node, the pods on this node are scheduled to other nodes. Make sure that the cluster has sufficient nodes. If no sufficient nodes are available, we recommend that you temporarily scale out the nodes before the node is drained.
Before you attach the data disk, run the df command on the node. If the output indicates that 
/var/lib/docker
is mounted to /dev/vdb1
, the data disk is attached to the node. Then, you can skip the following steps. If
the /var/lib/docker directory is not mounted, perform the following steps: 
After the node is added to the cluster, log on to the node and run the df command to check whether the data disk is attached to the node.
The following figure shows that the data disk is attached to the node. 

This way, the data disk is attached to the existing node.