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Mirroring failover warnings RRS feed

  • Question

  • Hi Experts,

    we are having frequent failover warnings in mirroring, and the timeout were set to 10 seconds mostly, and customer says  "that the server is not timing out since I'm running a continuous ping from the abc (witness) server.

    Please give me more information in regards to the cause of fail over? what I assume is since the timeout is set to just 10 seconds it is causing frequent failover warnings, Please advice me.

    Here are few errors from errorlog:

    Database mirroring connection error 4 '64(The specified network name is no longer available.)' for 'TCP://abcdef.Big.ad.local:5022'.

    Error: 1474, Severity: 16, State: 1.

    Database mirroring connection error 4 'An error occurred while receiving data: '10054(An existing connection was forcibly closed by the remote host.)'.' for 'TCP://abcder.Big.ad.local:5022'

    Thanks in advance.


    Thursday, March 5, 2015 2:19 PM

Answers

  • Read the recommendations of configuring partner 

    https://msdn.microsoft.com/en-us/library/ms366349(v=sql.100).aspx

    If you plan to use high-safety mode with automatic failover, the normal load on each failover partner should be less than 50 percent of the CPU. If your work load overloads the CPU, a failover partner might be unable to ping the other server instances in the mirroring session. This causes a unnecessary failover. If you cannot keep the CPU usage under 50 percent, we recommend that you use either high-safety mode without automatic failover or high-performance mode.

    Did you check with n/w team? If its n/w dropout then you can expect the failover. Work with n/w team and see if they find any thing useful.

    And

    If that is not the case,  Increase the timeout value to 20 seconds and see if this solves the problem.

    --Prashanth

    Thursday, March 5, 2015 5:48 PM