Irule question about Hash persistence

Are you using cookie hash persistence or the hash persistence profile which references an iRule?

 

 

What is the criteria you want to use the persist clients? Do you have two different web apps being hosted by the same LTM virtual server where you send requests to two different pools based on the host header value?

 

 

If you have two pools you want to select between based on host header and you want to use cookie insert persistence, you could add an iRule or two HTTP classes which select the pool and then use the default cookie insert persistence profile. This is described in a few posts:

 

 

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&tpage=1&view=topic&postid=6031860322

 

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=31&tpage=1&view=topic&postid=1753117547

 

 

Aaron

dupe

Thanks for the reply.

 

I am using hash_persistence profile which references an irule.

 

I have multiple web applications being hosted by one LTM virtual server. The LTM virtual server is DNS A record. My web applications' are DNS alias. I only have one pool. I have two nodes (two web servers) in that pool. I can see that all the http connections are only on one node. I want to balance the load to two nodes. My understanding is that when I type the web app's URL on a client computer, DNS is resoved and find the public IP of the LTM virtual server. The LTM virtual server has a hash_persistence profile assigned. The hash_persistence profile has a Irule assigned. According to the Host Header in the Irule, http request is forwarding to pool. The Pool uses Round Robin method. The load should be balanced.

 

What is the criteria I want to use the persist clients? The web applications are dotnet apps. I want to make sure the users always communicate to the web app on one web server where he/she first lands on before he/she logs out.

 

 

Thanks

Are the DNS aliases on the same domain? If you only have one pool and all pool members answer for both host header values, why are you inspecting the host header?

 

 

Have you tried removing the hash persistence profile, adding a cookie insert persistence profile and testing?

 

 

Aaron

I am trying to figure out why http requests are not balanced according to my above configuration. If LTM checks persistence after http request is trigged, the new requests should be forwarded to the other node in the pool. Not sure if I use the wrong irule.

 

 

Thanks

Are the DNS aliases on the same domain? If you only have one pool and all pool members answer for both host header values, why are you inspecting the host header?

 

 

Have you tried removing the hash persistence profile, adding a cookie insert persistence profile and testing?

 

 

Aaron

I am trying to figure out why http requests are not balanced according to my above configuration. If LTM checks persistence after http request is trigged, the new requests should be forwarded to the other node in the pool. Not sure if I use the wrong irule.

 

 

Thanks

Are the DNS aliases on the same domain? If you only have one pool and all pool members answer for both host header values, why are you inspecting the host header?

 

 

Have you tried removing the hash persistence profile, adding a cookie insert persistence profile and testing?

 

 

Aaron

I am trying to figure out why http requests are not balanced according to my above configuration. If LTM checks persistence after http request is trigged, the new requests should be forwarded to the other node in the pool. Not sure if I use the wrong irule.

 

 

Thanks

Yes, DNS alias are on the same doman. They are like "abc.AAA.com", "123.AAA.com", "xyz.AAA.com", etc.

 

[If you only have one pool and all pool members answer for both host header values, why are you inspecting the host header? ]

 

I have no idea why they use following irules to check headers. Is there anything I can improve the following irule if I still use hash_persistence? I will look into cookie insert profile. Thanks

 

 

if { [HTTP::header host] eq "xxx.AAA.com" } {

 

pool webpool}

 

 

elseif { [HTTP::header host] eq "xxx.AAA.com" } {

 

pool webpool}