We have a active/passive 2 node cluster. Win Server 2003 and SQL Server 2005. Problem: Node 1 had a hardware failure. It was traced back to faulty network cards. Cluster Server tried to failover to Node 2 and it failed because of several errors related network-related issues. My question is: Why did Node 2 fail and get removed from the Active Server Membership and how can we prevent this from happening in the future? Here are error messages: 1.CheckQueryProcessorAlive: sqlexecdirect failed. specified network name is no longer available 2. sqlstate 09s501 native error = 0. Communication link failure 3. ODBCConnectError: TCP Provider: Timeout expired 4. The MSDTC service is stopping. Cluster service was terminated by request from Node 1. 5. Cluster Network Name is no longer registered with its hosting system 6. The TCP/IP interface for Cluster IP address MSDTC IP Address has failed 7. Cluster Node 2 failed a critical operation. It will be removed from active server cluster membership. Check node is functioning properly and that it can communicate wit the other active server cluster nodes 8. node 1 lost communication with node 2 on heartbeat 9. node 1 lost communication with node 2 on public network 10. cluster resource MSDTC Network Name failed 11. Node 2 removed due to lost communication 12. KRB_AP_ERR_MODIFIED error from the server host Node1. The target name was CIFS/ Virtual SQL Server Name. Commonly this is due to identically named machine accounts in the target realm and the client realm. 13. Cluster service was halted to prevent an inconsistency with the server cluster. At this point, everything was up but the resources where offline. To bring it back, we simply brought the resources online and all was fine. Your thoughts are appreciated.