Failover on Active/Active/Active RRS feed

  • Question

  • I have the following situation.

    we have SQL 2008 R2 cluster active/active/active (a, b, c) and three instances run on this environment.

    We did a test on one of the instances, and failover test.
    1. Manual failover from node c to b.  After 3 minutes, the application cannot connect SQL.
    2. Back to node c we are OK and application is happy
    3. Manual failover from node c to a.  After 3 minutes, the application cannot connect SQL.
    4. Back to node c we are OK and application is happy

    Please give me some helps.
    Wednesday, March 13, 2013 3:18 PM

All replies

  • Before anyone attempts to help you could you tell us how your application connects to failover cluster instance on node C. Does it make use of failover cluster instance virtual name? or you are using direct node name to connect to SQL instance and what is the error message when it can't connect?

    Wednesday, March 13, 2013 3:24 PM
  • An application connects to a SQL virtual instance which connects to the Cluster Active-Active-Active.


    Wednesday, March 13, 2013 3:33 PM
  • So first thing terminology Active-Active-Active is confusing. In SQL Server clusters are either single instance (you call it active/passive) or multi instance (you call it active/active). what you have is multi instance SQL cluster. So by design each node has one instance running by default and in case of failover one of the node will have two SQL instances running. Ideally you should have n+1 node (in your case 4 nodes where one node is strictly for failover purpose). Now when you say application can't connect tell us what's the error received by application?   
    Wednesday, March 13, 2013 3:37 PM
  • I am not the one who manages the Cluster environment.  We have a group to manage this.

    Here is the error message:

    "EODBC Error Text: [IBM][SQLServer JDBC Driver]The requested instance is either invalid or not running."


    Wednesday, March 13, 2013 4:01 PM
  • How is your application connecting to the cluster? You have to use the virtual SQL Server name that will move with the SQL Server instance as it fails between nodes.

    If you are using the the hostname or IP address of Node C then the connection will fail when the instance is running on another node.

    Tuesday, March 26, 2013 5:53 AM
  • Is the firewall activated on all your servers ?  If yes, are they all configured the same way ?

    Friday, April 12, 2013 8:15 PM