[vCenter] How to Check and Increase Disk Space

Case: How does vCenter check disk space?

In vSphere, vCenter Server is the most reliable centralized management platform for efficiently provisioning, configuring, and monitoring the vSphere infrastructure.

When performing administrative tasks via vCenter, it is important to keep a close eye on the disk space usage to avoid potential issues that could cause downtime for VMs or prevent proper management of the environment.

If the disk space is insufficient, then you may receive errors similar to the following:

• vSphere UI Health Alarm, Log disk exhaustion on vCenter
• Database Health Alarm, Core and Inventory Disk Exhaustion on vCenter

By default, the error messages begin when the disk reaches 80% full; when some disks reach 95% full, the main vCenter service, vmware-vpxd, is turned off automatically to protect the database from corruption. Thus, the problem may cause vCenter Server to be inaccessible with 503 Service Unavailable errors.

Next, this article will show you how use vCenter check disk space, and increase vCenter disk space if needed.

Extended reading: possible causes for disk partitions running out of spaces

The best way to solve a problem is to find the right cause and apply the right measure, sometimes multiple issues cause by multiple possible causes. At least get a general understanding of them.

The disk exhaustion issue is one of this type. There are many possible causes for specific disk partitions running out of space, including:

• Partitions are not sized correctly
• Large files in the partitions
• Tables in the database consuming space
• Services are failing to clean up files

How to check disk space from vCenter

As you received the alerts, the first thing you need to do is to find out which disk has this issue. There are many ways you can choose to check vCenter datastore usage on disk. This part will present you how to use VAMI or SSH for vCenter check disk space.

Check disk space via vCenter GUI

1. Log In to the vCenter Server Appliance Management Interface (VAMI)​​​​​​.

2. Select Monitor > Disks.

3. Note which disks are showing 78% or higher usage. Please note that in version 6.7 and higher versions, the /storage/archive disk can be up to 100% full by design. Thus, the “archive” disk being 80% or more full can be safely ignored​​​​.

Check disk space via BASH Shell

1. Log in to the vCenter Server Appliance as root via SSH or the vCenter virtual machine Console.

2. Run this command to enable the Bash shell:

shell.set --enabled true

3. Type shell to switch to the BASH Shell.

4. Run the following command to get a list of the statistics about the total, used and available space on each storage.

df -h

Find out which partitions are full enough to trigger warnings, 78% or more full.

Or you can also use the alternative command which only shows you the partitions which are getting full:

df -h |awk '0+$5 >= 78 {print}'

Note: We’re looking for “78” because in many cases if the partition is at 78-79%, it may be exceeding the 80% needed to trigger warnings, then recovering back to the lower percentage. Similarly, if it is at 93%, it may be exceeding the 95% needed to trigger vmware-vpxd service to shut down, then recovering back to the lower percentage.

How to increase vCenter disk space

Now you know which hard disk has the disk exhaustion issue. You can extend the disk space to fix it.

Before you start, please find the exhausted disk name via VAMI or SSH. And ensure there is no snapshot attached to the vCenter Server VM.

Here are the detailed steps:

1. Log in to the vCenter Server Appliance using SSH and root credentials.

2. Run this command to enable the Bash shell:

shell.set --enabled true

3. Type shell and press Enter.

4. Run the following commands to verify which disk is experiencing disk capacity issues, then trace which SCSI ID will show in the VM edit settings:

df -h; lsblk; lsscsi

5. Log in to vSphere Client, power off and right-click on the vCenter Server Appliance VM, and select Edit Settings.

6. From Virtual Hardware tab, click on Hard disks to open its dropping down menu.

7. Select the exhausted disk and manually increase the size of the disk. Ensuring there is no snapshot attached to VM.

8. After the virtual disk is increased, return to the SSH session and run the following command to automatically expand any logical volumes for which the physical volumes are increased:

/usr/lib/applmgmt/support/scripts/autogrow.sh

9. Confirm that the virtual disk has successfully grown:

df -h

Summary

Keeping an eye on the vCenter datastore usage on disk is an important task for virtualization administrators. By regularly checking disk space usage and freeing up space, you can avoid many potential issues caused by insufficient storage. This article showed how vCenter check disk space and how to increase vCenter disk space.

Except for regular monitoring, you also need to backup important data to avoid accidental loss. As for VM data, AOMEI Cyber Backup is a reliable and efficient ESXi VM backup software for you to have a try.