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We have a small web cluster for servering about max 400 concurrent user each day.

We using :

  • Apache 2.2.14
    • mod_proxy
    • mod_proxy_httpd
    • mod_proxy_balancer
  • JBoss 4.2.2 GA

Firstly we tried AJP and unforutanly we got AJP CLOSE_WAIT problem which caused apache not response to HTTP request. So we turn to mod_proxy_balancer, it looks not have the same CLOSE_WAIT problem in each JBoss node.

Here is our configuration for mod_proxy_balancer now:

<Proxy balancer://www>
       Allow from all                                    

       BalancerMember loadfactor=10 route=node1

       BalancerMember loadfactor=10 route=node2

       BalancerMember .... loadfactor=10 route=node3

       ProxySet lbmethod=byrequests stickysession=JSESSIONID|jsessionid nofailover=On


ProxyPass /LEI balancer://www/

ProxyPassReverse /LEI balancer://www/

But we got a new problem here, there were many (hundreds of ) CLOSE_WAIT we can find from the apache node machine:

netstat -a | grep CLOSE_WAIT
tcp        1      0 localhost:30997       localhost:webcache     CLOSE_WAIT 

Is this a problem of mod_proxy_balancer? How can we avoid this?

We have read all post about CLOSE_WAIT in this forum and tried many solutions when we using AJP.

Are they any other http cluster solutions without using Apache mod_proxy_balancer?

BTW: We have read nginx and it only support balance based on client IP router, right? Most of our users are inside one large intranet (campus users).

Thanks for any help.

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