tomcat中的会话迁移/复制

Question

I have N number off application servers all behind a hardware load balancer.Now i want to make these app server session aware?

If i create a session on one appserver other app server will not be aware of it.After googling i found 2 approaches 1)Generate a random String .Put this randomString in cookies and store these in Db table with creation time.Very time when request comes in check this db table.But this opration is heavy 2)Use tomcat session migration?Now am sure if this works correctly .Does this work correctly?

Am using TOMCAT as my web server (Cant use other)

How can i configure tomcat for session migration/replication?Any tutorial?

Answer 1

Session replication is a pretty broad topic. Have you tried the Tomcat built-in replication yet?

http://tomcat.apache.org/tomcat-6.0-doc/cluster-howto.html

If that's not good enough for you, you can look for commercial tools like Terracotta Web Sessions. Or you could develop your own session cache around for example memcached.

Answer 2

I am not aware about the session affinity when working behind a hardware load balancer ,However for the scenario that you have mentioned as per your googling results for the 1st part you can use Memcache instead of cookie+database to reduce the operation response time . A simpler approach when using Memcache can be using "memcached-session-manager" .The setup and configuration is easy as mentioned at at http://code.google.com/p/memcached-session-manager/wiki/SetupAndConfiguration .