Setup details –

1. H/W Load Balancer
2. Two Apache Servers with load balancing and rewrite rule
3. Two Application servers

Request will be travel 1 then 2 then 3

Queries –
1. When any session is established I can see that requests of that session is going to both the application servers. Unique jsession id is assigned to that request, using that jsessionid request is forwarded to both application servers. Is it expected behavior?

2. In configuration of Apache load balancing what is good configuration
• By Request
• By Traffic

3. In apache configuration we add route parameter in Proxy balancer tag for both application server, then it gets appended to jsessionid like jsessionid=50D8494884F6D4E9FFB8D8946AEB5AC7:s1 and apache server will use this pattern to manage sessions. In my case this route is not added at the end of jsessionid. Is this something which can cause session issue? In log it shows that it is attached to s1/s2 route respectively.
BalancerMember http://server.1 loadfactor=1 route=s1
BalancerMember http://server.2 loadfactor=2 route=s2

4. Sometimes I am getting this error and land me on error code 400 page not found.
[Tue Jun 22 06:17:32 2010] [error] [client 166.23.23.32] Invalid URI in request username=test&password=1234&method%3Alogin=Logga+in&__checkbox_rememberMeChecked=truejpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*, referer: http://server1.server/home.action

This all happen when we are accessing URL using hardware load balancer. If we hit each apache server individually everything is working fine.

Please reply.