Remediating an ESX Server host using Update Manager might leave the ESX Server host in a Not Responding state from VirtualCenter and the following error message is reported:
An error occurred while communicating with the remote host.
The remediation process fails with the error:
VMware Update Manager had a failure.
At the end of remediation, Update Manager might also fail to exit maintenance mode for the ESX Server host. The following message is logged:
Unknown Host Error: Failed to exit host from maintenance mode
In this situation, Update Manager might not be able to install the rest of the necessary bundles or packages for a given patch.
If you have created a baseline that includes patch bundle ESX350-200803202-UG, you might also see the following error message logged in hostd.log :
error: Signature mismatch between VmkCtl (May 26 2008 13:34:49) and VMKernel