Forum Discussion

Dowlas_Lobo's avatar
Dowlas_Lobo
Icon for Nimbostratus rankNimbostratus
Dec 09, 2012

BIG IP LTM and JBOSS Session Replication.

Hi,

 

 

I am new to F5 LTM & iRules and need some help to find a solution using iRules for the below issue.

 

 

We are currently using F5 BIG-IP LTM 3900 version 10.2.4. I have configured a virtual server X to load balance traffic between 4 webservers(A,B,C and D). All web servers are in a single pool and the stickyness configured is cookie based.

 

Web server A and B are internally pointing to JBOSS cluster01 with 2 nodes and web server C and D are pointing to JBOSS cluster02 again with 2 nodes. Session replication is configured within the JBOSS clusters. Everything work fine in normal situation.

 

 

Issue.

 

 

When client request comes to the virtual server X, the LTM forwards the request to web server A and web server A internally forwards the request to JBOSS cluster 01. All works fine for the user till the webserver A fails in the middle of the transaction. Now when the client send traffic within the same session the LTM forwards the traffic to web server D, but as the cluster behind the web server D is Cluste02 the transaction fails. The session replication is within cluster nodes and not across clusters.

 

 

Solution Required:

 

 

Is there a way by using iRules to restrict the LTM to send the session connected to web server A to only webserver B in case A fails. It should not go to C and D as Web Servers A and B point to cluste01 at the backend and same session is available from webservers A or B. The same should be for web server C and D.

 

 

 

 

 

application delivery
dev
devops
iRules

2 Replies

Sort By
  • hooleylist's avatar
    hooleylist
    Icon for Cirrostratus rankCirrostratus
    Dec 11, 2012
    Hi Dowlas,

     

     

    Can you check this Codeshare example to see if it fits your scenario?

     

     

    https://devcentral.f5.com/wiki/iRules.Weblogic-JSessionID-Persistence-for-Session-Replication.ashx

     

     

    Aaron
  • Torti's avatar
    Torti
    Icon for Altostratus rankAltostratus
    Feb 04, 2014

    so you don't want to load balance, you want to do a failover only? Then you can try PGA (Priority Group Activation) PGA There is an example in the middle of the manual.

    Try it with 

    min active member 1
server A priority 4
server B priority 3
server C priority 2
server D priority 1