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Samit_jadhav_33's avatar
Samit_jadhav_33
Icon for Nimbostratus rankNimbostratus
Feb 19, 2019

Issue in Failover of pool member

Scenario

 

2 pool members A & B behind ltm. Load balancing method .. Round robin No persistence Monitoring Probe used tcp_8443 Interval set to 2 sec Timeout 7 sec

 

Issue... Client experiences delay of 10 sec while initiation of Failover of URL from pool member A to pool member B

 

Could anyone advise how could this delay be reduced?Thanks!

 

18 Replies

  • Hi,

     

    You configured two poole members with round robin method. First request will go to A and second request will go to B. I suggest you configure persistence based on your application requriement.

     

    Your application is using any cookie method ? if yes you can go with Cookie persistence.

     

    • Samit_jadhav's avatar
      Samit_jadhav
      Icon for Altostratus rankAltostratus

      Hi Raghvendra, Application isn't using any cookie persistence.

       

      If persistence isn't set then what will be default persistence value?

       

      When the Failover of poolmember takes place , do I need to try to open url his different pc ?

       

  • Hi,

     

    You configured two poole members with round robin method. First request will go to A and second request will go to B. I suggest you configure persistence based on your application requriement.

     

    Your application is using any cookie method ? if yes you can go with Cookie persistence.

     

    • Samit_jadhav's avatar
      Samit_jadhav
      Icon for Altostratus rankAltostratus

      Hi Raghvendra, Application isn't using any cookie persistence.

       

      If persistence isn't set then what will be default persistence value?

       

      When the Failover of poolmember takes place , do I need to try to open url his different pc ?

       

  • If cookie persistence is not there, then go with source based persistence with default Timeut value (300seconds). Please make sure your TCP profile timout and persistence timout has same values.

     

    • Samit_jadhav's avatar
      Samit_jadhav
      Icon for Altostratus rankAltostratus

      But if the source based persistence is used then it may take 5 min to hit the client traffic on next available poolmember when the 1st pool member goes down and the requirement is clients traffic should switchover to next available pool member within 4 sec whenever the 1st pool member goes down...

       

    • RaghavendraSY_7's avatar
      RaghavendraSY_7
      Icon for Cumulonimbus rankCumulonimbus

      If your requirement is failover traffic to pool member B only if pool member A goes down? If Yes to the question then you need to go with Ratio load balance method and no need to use persistence.

       

      Ration method:

       

      Pool A --100% Pool B --0%

       

      Hope this helps.

       

    • Samit_jadhav's avatar
      Samit_jadhav
      Icon for Altostratus rankAltostratus

      Thanks Raghvendra, but after setting lb method to ratio , will the Failover take place in 4 sec

       

      anyways I'll set probe interval timings to 1 sec and probe timeout value to 4 sec , will this help me in achieving my target of Failover in 4 sec?

       

  • If cookie persistence is not there, then go with source based persistence with default Timeut value (300seconds). Please make sure your TCP profile timout and persistence timout has same values.

     

    • Samit_jadhav's avatar
      Samit_jadhav
      Icon for Altostratus rankAltostratus

      But if the source based persistence is used then it may take 5 min to hit the client traffic on next available poolmember when the 1st pool member goes down and the requirement is clients traffic should switchover to next available pool member within 4 sec whenever the 1st pool member goes down...

       

    • RaghavendraSY's avatar
      RaghavendraSY
      Icon for Altostratus rankAltostratus

      If your requirement is failover traffic to pool member B only if pool member A goes down? If Yes to the question then you need to go with Ratio load balance method and no need to use persistence.

       

      Ration method:

       

      Pool A --100% Pool B --0%

       

      Hope this helps.

       

    • Samit_jadhav's avatar
      Samit_jadhav
      Icon for Altostratus rankAltostratus

      Thanks Raghvendra, but after setting lb method to ratio , will the Failover take place in 4 sec

       

      anyways I'll set probe interval timings to 1 sec and probe timeout value to 4 sec , will this help me in achieving my target of Failover in 4 sec?