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Nate83_280180's avatar
Nate83_280180
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Apr 05, 2017

priority groups and priority group activation

Hi, newbie here. I have a VS setup with 1 pool, that has 4 members. 2 members are set in a priority group with no.10, the other 2 in priority group with no.5. Priority group activation is set to Less than 1 available member.

 

So, the requirement now is, when either of the members fail in PG10, traffic needs to go to PG5, regardless if the other member in PG10 is available. So essentially traffic gets failed over and stays there.

 

And the same scenario for when PG5 loses a member. Traffic needs to go back to PG10 and stay there.

 

Question is, can this be done? And are priority groups and PG activation the way to go for this? Is there an iRule that can facilitate this better?

 

Thanks in advance for any responses, hope the explanation was clear enough.

 

  • Hi Nate,

     

    Looking at your requirements, failing from PG10 to PG5 is completely achievable using PGA.

     

    Your latter requirement isn't possible using standard configuration.

     

    The only achievable way you could do that with 1 Pool, was if your application/server was capable of listening on multiple ports, and you could have PG10 with your preferred members, and then cascade down through orders of preference combinations based on other PG statements.... But this would get messy ! It hurts my head even thinking about it!

     

    Another way would be to use a fallback pool on the Virtual Server, and if PGA members for PG10 and 5 are down. Use the fallback pool...

     

  • Hi Nate,

     

    Looking at your requirements, failing from PG10 to PG5 is completely achievable using PGA.

     

    Your latter requirement isn't possible using standard configuration.

     

    The only achievable way you could do that with 1 Pool, was if your application/server was capable of listening on multiple ports, and you could have PG10 with your preferred members, and then cascade down through orders of preference combinations based on other PG statements.... But this would get messy ! It hurts my head even thinking about it!

     

    Another way would be to use a fallback pool on the Virtual Server, and if PGA members for PG10 and 5 are down. Use the fallback pool...

     

    • Nate83_280180's avatar
      Nate83_280180
      Icon for Nimbostratus rankNimbostratus

      HI Iain,

       

      Yeah, that's what I figured. Currently testing PGA with destination address persistence, which could potentially give most of the requirement. Will let you know how it turns out.