VMware vSphere • Re: Failed to open VDDK disk

Reviving an old thread, but I stumbled upon this searching for help for my issue.

I had exactly the same problem when trying and migrating to production an instant-recovered VM. The task kept failing with

18/08/2025 10:29:55 :: Copying snapshot files Error: Failed to open VDDK disk [[*****] ****DCA/****-DC01.vmdk] ( is read-only mode - [false] )
Logon attempt with parameters [VC/ESX: [192.168.*.***];Port: 902;Login: [root];VMX Spec: [moref=14];Snapshot mor: [14-snapshot-1];Transports: [nbd];Read Only: [false]] failed because of the following errors:
Failed to open disk for write.
Failed to download disk 'vddkConnSpec>'.
Agent failed to process method {DataTransfer.SyncDisk}.

In my case the VM are backed up directly from the nodes (the vCenter is not registered with Veeam), and the VCSA prevented the migration to complete. I just shut down the VCSA (didn't have to disconnect the ESXi from the vCenter) and was immediately able to complete the migration.

Statistics: Posted by Moebius — Aug 18, 2025 10:53 am

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