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robor_127995
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Oct 19, 2007

Failover IP in the pool ?

Hi,

 

 

I would like to know how to implement the fallback IP on the pool, it is specific for GTM or LMT software ? (When the pool is not available the http request shall be directed to the fallback IP address) Does the iRule could cover such functionality ?

 

 

Bregs,

 

robert

3 Replies

  • Hi,

     

     

    I'm not sure about the GTM functionality, but you can configure a fallback host in the HTTP profile which LTM will send in a 302 redirect when all pool members are marked down by a monitor. Try searching on AskF5.com for "fallback host" for more details.

     

     

    Aaron
  • Hi,

     

     

    Unfortunately I would like to avoid the HTTP profile redirect functionality and directly send the request towards the alternative pool.

     

    Would you be so kind to propose the solution without hte fallback IP in the HTTP profile.

     

     

    Bregs,

     

    robert
  • If you want to use another set of servers to handle the requests, the ideal solution would be add them to the pool as lower priority members. You can configure the pool so that only the higher priority members are used by default. You can check the LTM configuration guide on AskF5.com for your version for details. The lower priority members are used only if the higher priority are all marked down.

    Else, if you want to use a rule, you could use something like this:

    
    when CLIENT_ACCEPTED {
        check if the default pool on VIP has no active members
       if {[active_members [LB::server pool]] < 1}{
           default pool on VIP has no active members
          pool fallback_pool
       }
    }

    This rule is triggered when a TCP connection is established with a client. [LB::server pool] returns the name of the default pool configured on the virtual server. [active_members POOL_NAME] returns the number of members in the pool that are not marked down. If there aren't any active members, the fallback_pool is used for the duration of the TCP connection.

    Aaron