This holds the numeric error code returned by the remote invocation -- the API call UCS Manager made to vCenter -- the last time this provider's FSM issued one. This is the field to check first when a vCenter integration fails, because it carries vCenter's own error code back through UCS Manager rather than a generic UCS-side failure code; pairing it with fsmRmtInvErrDescr on the same Provider object gives the actual reason vCenter rejected the call. A nonzero code here alongside an 'invalid credentials' description points straight at the service account UCS Manager uses to log into that vCenter.