Workaround for Overlay Volume Auto-Resize Failure in PMC 4.2.1

PMC 4.2.1 includes an automatic mechanism that expands file systems at boot when their underlying virtual disks or partitions are resized in the hypervisor. However, we have observed that this process may fail on certain hypervisors. This issue is planned to be resolved in the upcoming PMC 4.3 release.

In the meantime, if the Overlay volume does not resize automatically, follow the steps below to manually extend the file system.

1. Shut Down the PMC Appliance

Power off the PMC virtual machine from the hypervisor interface.

2. Expand the Overlay Volume in the Hypervisor

Use the tools provided by your hypervisor to increase the size of the Overlay disk/volume.

• On-prem PMC 4.2.1: default Overlay volume size = 2.0 GB
• Azure deployments: default Overlay volume size = 5.0 GB

Increase this volume to the desired capacity.

3. Boot PMC and Log In

Start the PMC appliance and log in with a user account that has Device Administrator permissions.

4. Verify Overlay Volume Size

Open the PMC Dashboard and confirm whether the Overlay volume size reflects the new expanded value.

If the size is not updated, continue with the manual steps below.

Manual File System Extension Procedure

5. Identify the Overlay Storage Device

Run the following command in the PMC terminal:

root@localhost:~# df -h

Look for the device mounted at:

/run/live/overlay

Example output:

Filesystem      Size      Used     Avail     Use%     Mounted on

udev                1.9G     0            1.9G       0%     /dev

tmpfs             390M    564K   389M       1%     /run

/dev/xvda1     7.8G    1.2G      6.2G      16%     /run/live/medium

/dev/loop0     1.2G     1.2G        0       100%     /run/live/rootfs/filesystem.squashfs

/dev/xvdb       2.0G     126M   1.7G       7%     /run/live/overlay

overlay            3.6G     193M    3.3G       6%     /

tmpfs              2.0G      0            2.0G       0%     /dev/shm

In this example, /dev/xvdb is the Overlay volume device.
Device names may differ across hypervisors (Citrix Hypervisor typically uses xvdb; VMware or Hyper-V may show different identifiers

6. Manually Extend the File System

Run:

resize2fs <overlay-device>

Replace <overlay-device> with the actual device name found in the previous step.
Example:

resize2fs /dev/xvdb

This command will expand the ext4 file system to use the full size of the enlarged Overlay volume.

7. Confirm the Expansion

Return to the PMC Dashboard and refresh the Volume and Storage Space information.
The Overlay volume should now show the updated, expanded size.