I was trying to attach two domaincontrollers that were located not in the same domain as the Data Protection Management server, but in a trusted domain. Multiple domains exist in this forrest.
I could reach the DPM-server from each of the machines, but every time i tried to attach or install the servers to the dpm the task failed with the above error.
Connecting the DPM agents to the server would fail with Error 346 and a reference to the WMI (Windows Management Instrumentation) not being read.
Start with the basics and start pinging.
ping *full FQDN hostname*
example : ping DC1.production.domain1.com
ping *NETBIOS name*
example: ping DC1
You should be getting the same results.
If not : try setting the correct ip’s in the hosts file just to make sure the hosts resolve.
Run > notepad C:\windows\system32\drivers\etc\hosts
The DPM server will now find the correct hosts you wish to attach.
I’m still not quite sure what caused this, but i am assuming that the trust to the other domains and the fact those domains also feature DC1 and DC2 hosts messed up the dns resolving for the DPM.
All other DPM Error 346 references i foudn were related to firewalling and broken WMI services, but none mentioned the fact that dns resolving could be the issue.
I do realise this is a bit of a dirty fix, but i also assume that other professionals will be able to adjust the dns servers and change persistent routes to reflect a more “acceptable” fix.
Excellent troubleshooting document : http://blogs.technet.com/b/dpm/archive/2012/02/06/data-protection-manager-agent-network-troubleshooting.aspx