Problem description
VMWARE VM backups fail with Phoenix 1 Internal Error
Traceback
Review the Phoenix and VDDK Logs
Phoenix.log
[2021-12-28 23:45:50,521] [ERROR] PhoenixApiCore: Error while stream write for stream data_6000C293-059a-ad9d-52fa-f4f080e3faf7 at offset=12749635584. Error: Internal error. (#100000001) (Error Code : PHOENIX1)
VDDK Logs
2021-12-29T23:03:42.476+05:30| host-10443| I125: 2021-12-29T23:03:42.476+05:30 warning -[10443] [Originator@6876 sub=cleanup] Could not unmount /tmp/vmware-root/42317aeb-2f5e-de60-866b-abcf40e78fd3-vm-6407/hotadd: Internal error occurred. 2021-12-29T23:14:41.808+05:30| host-10443| I125: 2021-12-29T23:14:41.808+05:30 warning -[10443] [Originator@6876 sub=cleanup] Could not unmount /tmp/vmware-root/42317aeb-2f5e-de60-866b-abcf40e78fd3-vm-6407/hotadd: Internal error occurred.
Resolution
Manually unmount the VMDK from a backup proxy through vCenter.
Steps to unmount a VMDK from a virtual machine
Power off the backup proxy.
Right-click the virtual machine and click Edit Settings.
Verify the Hard Disk by Disk File information.
Once the Hard Disk has been verified that you want to remove it, an X mark will appear on the right side of the selected line (DO NOT select the option Delete files from data store).
Click on the X mark to remove the disk.
Press OK.
Verification
Run the backup verify the solution.