Forum Discussion
AltostratusUnable to use cookie persistence with ISA and CAS
Customer has a pair of ISA to terminate HTTPS connections for the 3 backend CAS servers. LTM is located between ISA and CAS. So below setup.
client -------> ISA --------> LTM ----------> CAS
HTTPS HTTP HTTP
The VS for the HTTP connection is configured with cookie persistence, and source address persistence as fallback. We find that the VS is using source address persistence but not cookie persistence. As all connections are from the two ISA servers so sometimes nearly all connections are load balanced to the same CAS server.
How can I troubleshoot why it is not using cookie persistence? Or I should use other persistence methods?
5 Replies
What_Lies_Bene1Cirrostratus
What load balancing method is configured? Why do you believe source address persistence is being used instead of cookie?
As it's HTTP you should easily be able to do a tcpdump on the LTM and inspect the traffic and payload closely. Are you familiar with tcpdump?
Daniel_55334I see in the statistics of persistence records and all are using source ip address.
I am fine with tcpdump. But what information I should exactly look into?
- What_Lies_Bene1Funnily enough I answered another post today about this and had to do some research. Anyway the upshot is that yes, the fallback persistence profile creates records, but doesn't use them unless the primary method fails. They both operate at the same time but LTM won't use the fallback unless it needs to.
For the tcpdump, you just want to make sure you can see the persistence cookie being passed back and forth. If you do, all is well. - Daniel_55334Yes it just comes to my mind that there should be no cookie persistence records in the statistics. I will try to see if there is cookie received on the client. THanks for your reply.
- What_Lies_Bene1You're welcome, let us know what you find, either way.
