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ekanathdas_2662's avatar
ekanathdas_2662
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Nov 10, 2010

Failover between pool members

Hi,

 

In v9 LTM, there are four pool members(PM 1, PM 2, PM 3 and PM 4) under a pool.

 

 

The requirement is if at all PM1 and PM2 are up and active , PM3 and PM4 are inactive.

 

When PM1 and PM2 are inactive, PM3 and PM4 comes up.

 

 

In short its moreover like failover rather than loadbalancing.

 

 

What needs to be configured to attain the above requirement.

 

 

Thanks,

 

Ekanath

 

 

5 Replies

  • Hi Ekanath,

     

     

    If I understand the scenario correctly, I think you can use priority group activation with PM1 and PM2 set to a higher priority than PM3 and PM4. You can search in the LTM config guide for your version under pools for details.

     

     

    Aaron
  • As per the document in F5, the highest priority is preferred if there are atleast of 2 active pool members(highest priority) , when the count is less than 1, Ltm sends the traffic to the next higher priority pool members.

     

     

    If there are only two pool members which will server the Virtual Server , will the below settings send the traffic to the second server if the primary server fails?

     

    Server1 priority 2

     

    server2 priority 1

     

     

    Or I have to assign the servers two different pools and then use the below I rule to serve the purpose:

     

     

    when LB_FAILED{

     

    if { [active_members poolserver1] == 0 } {

     

    pool poolserver2

     

    }

     

    }

     

     

    ----

     

    Thanks,

     

    Ekanath

     

  • Posted By ekanathdas on 02/16/2011 06:46 AM

     

    As per the document in F5, the highest priority is preferred if there are atleast of 2 active pool members(highest priority) , when the count is less than 1, Ltm sends the traffic to the next higher priority pool members.

     

     

    If there are only two pool members which will server the Virtual Server , will the below settings send the traffic to the second server if the primary server fails?

     

    Server1 priority 2

     

    server2 priority 1

     

     

    Or I have to assign the servers two different pools and then use the below I rule to serve the purpose:

     

     

    when LB_FAILED{

     

    if { [active_members poolserver1] == 0 } {

     

    pool poolserver2

     

    }

     

    }

     

     

    ----

     

    Thanks,

     

    Ekanath

     

     

    If you only have Server1 (P2) and Server2 (P1) and Server 1 fails, Server2 will handle the traffic. You shouldn't need two different pools here.