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VM backups failing with INTERNAL65535 due to issues with nvram entry in the vmx

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Problem description

VM backups failing with Error: INTERNAL65535


VM was converted from Physical to Virtual Machine causing issues with nvram entry in the vmx file.


[2024-02-18 23:03:08,597] [INFO] VMX fpath: [Unity_Datastore02] BTC-SVR-BLACKHOLE/BTC-SVR-BLACKHOLE.vmx
[2024-02-18 23:03:08,598] [ERROR] Error <type 'exceptions.TypeError'>:cannot concatenate 'str' and 'NoneType' objects. Traceback -Traceback (most recent call last):
File "agents/vmware/", line 1766, in do_retry
File "agents/vmware/", line 1952, in get_nvram_from_datastore
File "agents/vmware/", line 1939, in __get_nvram_path
TypeError: cannot concatenate 'str' and 'NoneType' objects


Re-register the VM using the vmx file:

  1. Locate the VMX file of the affected VM.
  2. Open vCenter and navigate to the relevant datacenter and host.
  3. Right-click on the host and select "Browse Datastore."
  4. Upload the VMX file to the datastore.
  5. Right-click on the uploaded VMX file and select "Register VM."

If the issue persists, follow the workaround:

Workaround: Re-creating the VM using the existing disk:

  1. Shutdown the affected VM.
  2. Verify the absence of a generic nvram file.
  3. Add the following nvram parameter to the VM configuration file (VMX): nvram = "<vm name>.nvram"
  4. Power on the VM.
  5. Run a backup for the system to ensure data integrity.

Alternate Procedure for Workaround:

  1. Shutdown the VM.
  2. Confirm the absence of a generic nvram file.
  3. Edit the VMX file and add the nvram parameter: nvram = "<vm name>.nvram"
  4. Power on the VM.
  5. Perform a system backup to safeguard your data.

Additional Notes:

  • Always ensure that you have a recent backup before making any changes to the VM configuration.
  • The workaround provides an alternative method for resolving registration issues by recreating the VM using the existing disk.
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