Complete Apache 2.2-AJP Load Balance via mod_proxy

Complete guide for apache-http server load balancing via mod_proxy and some performance enhancements

required modules:


1. open your java application AJP connector

for tomcat un comment AJP connector as below

<Connector port=”8009” protocol=”AJP/1.3″ redirectPort=”8443″ />

2. Load Apache modules

include or uncomment those lines at httpd.conf

LoadModule proxy_module modules/
LoadModule proxy_ajp_module modules/
LoadModule proxy_balancer_module modules/

3. write new httpd-conf as httpd-ajp.conf

<Location /balancer-manager>
SetHandler balancer-manager

<Proxy balancer://ajpCluster>
BalancerMember ajp://localhost:8009 route=s1
BalancerMember ajp://localhost:9009 route=s2
BalancerMember ajp://localhost:7009 route=s3
<Location /jspapp1>
ProxyPass balancer://ajpCluster/jspapp1 stickysession=JSESSIONID
<Location /jspapp2>
ProxyPass balancer://ajpCluster/jspapp2 stickysession=JSESSIONID

/balancer-manager is to monitor your load balance cluster nodes

you can see fails and last status for java ajp connectors/Servers


Proxy balancer://ajpCluster

is your load balance /cluster definition for your apache server

in example is assuming 3 java application server with ajp connectors at 7009,8009,9009 working at at localhost

/jspapp1 and /jspapp2 is your jsp/java applications rename it with your application context name

4. Extras (GZip)

define mod_deflate in httpd.conf

LoadModule deflate_module modules/

add gzip compression for jspapp s

<Location /jspapp2>
ProxyPass balancer://ajpCluster/jspapp2 stickysession=JSESSIONID
AddOutputFilterByType DEFLATE text/html text/plain text/xml


multiple tomcat instance – single setup

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  • Comments (11)
    • yongcheolKim
    • January 31st, 2008


  1. great tips. thank you!

  2. Great post, this got me proxying requests via ajp_proxy from Apache to multiple virtual Xen instances running tomcat6 on the back end. Very cool, appreciate the effort.

  3. Hi Dear,

    I have configured the same but whenever my one instances goes down applications is not switching on another…..can u guid me ..


    • hi lovelesh,
      I am not sure but it was working,
      you can check, /balancer-manager if all your applications are running or not ?

      but there can be one problem i guess, your java server may be not dead (its ajp port is still open) but crashed by out-of-memory errors ? and not responding properly !

  4. oh cool, this information is really useful and definately is comment worthy! hehe. I’ll see if I can try to use some of this information for my own blog. Thanks!

    • Raghu boyalakuntla
    • April 16th, 2010

    this is really a vague inforation. can you please provide some clear step by step , how do we setup the mod_proxy.
    i have difficulty in understanding the Step 3. Is that to change the existing httpd.conf to http-ajp.conf?
    -Raghu boyalakuntla

    • Rakesh
    • July 16th, 2010

    Cool man grt article ;-)

  5. Nice. Worked for me, Thanks

    • Joel
    • November 25th, 2011

    Hi guys, Thanks for the wonderful post here.
    I have a problem to load mod_deflate .so. I get following error

    httpd: Syntax error on line 61 of /app3/apache2/conf/httpd.conf: Cannot load /app3/apache2/modules/ into server: /app3/apache2/modules/ undefined symbol: inflateEnd

    Please help me on this.
    Thanks in advance.

    • hi Joel,
      it seems you have incompatible so module with your server library, be sure you get the same ‘so’ library version/build number with your apache version.

      in most cases you need to build them all locally or get the whole distribution from one place.


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