HCX Interoperability with Backup Solutions

Products

• VMware HCX

Issue/Introduction

• Attempting to run a vMotion of any type results in an error stating a disk could not be accessed

• A backup job is running from a third party appliance/product (e.g. Commvault)

• Backup snapshot job fails with the following error:  "Unable to create a snapshot on virtual machine [VMName] because another task is already running on the virtual machine."

• Large SQL and App VMs that are syncing via HCX become unresponsive after a third-party backup is taken

• Tasks such as removing snapshots on VMs become hung and causing the HCX sync to stall and VM to become unresponsive.

Environment

VMware HCX
VMware vSphere ESXi
VMware vSphere vCenter
Third party snapshot based backup solution

Cause

Running backup services that use VM snapshots or taking snapshots of VMs while being migrated can disrupt the migration process. This is due to the VMDK locking process and is by design in order to avoid data corruption and prevent any impact to HCX services.

Resolution

• HCX DR provides the ability to protect VMs via ongoing replication. Taking snapshots can cause issues with the replication process. 

• In order to prevent any impact in HCX services, it may be required to stop snapshot based backup services prior to initiating a migration, using RAV, or bulk migrations.

• As workaround it would be recommended to configure file level backups for the migration duration as it does not involve in taking a snapshot of the VM.

Additional Information

Snapshot based backups must be paused before the HCX migration starts and can be resumed when the migration/switchover is completed.