Challenge
Job fails with error containing “VDDK error: 1.Unknown error”.
Cause
This issue occurs when too many performance counters are being registered on the ESXi hosts vpxa process causing the process to run out of memory.
Solution
According to VMware KB 2144799, this issue is resolved in ESXi 5.5 Patch 08 and ESXi 6.0 Patch 03.
If upgrade is not an immediate option, the KB also outlines a workaround that does not persist through reboot.
