Issue – VM Creation from template randomly failing with error 2940.
This issue started few days back and its random. My initial thought was that the HyperV host got some issues. However, this issue started with all nodes randomly.
Coincidentally , I observed that from VMM server HyperV Manager is not able to connect to the problematic server.
This error made me to check on the network side.
Ping HyperV host from SCVMM Server – Successful
Telnet port 135 of HyperV host which is used by RPC – Sucessfull
Googled this RPC issue and hit on the Technet wiki article, which made me to think again on the DNS part.
From SCVMM server, Opened NSLOOKUP and searched for the records for HyperV host. Yea – got some clue. I noticed three entries for this server.
Now I realized. I did created few Virtual Network Adapters on top of the Logical Network. Each Virtual Network Adapter is in fact linked with a particular subnet which has a DHCP scope of few IPs to enable ADJoin through template. Due to this, the Virtual Network Adapters got an IP from DHCP which got registered with DNS.
Unchecked “Register the connection’s address in DNS” from each Virtual Network Adapters and then ran ipconfig /registerdns .
This removed the duplicate entries from DNS. However – issue still exists.
From the HyperV host, tried to ping SCVMM host which was not successful. This made me to check the route.
For 0.0.0.0 destination, the server is having multiple paths with different metric. Even the one with highest metric was the actual route, traffic is getting routed through other interfaces randomly. For all Virtual Network Adapters, allocated a static IP and everything started working. Just a cool breeze !