proxy: AJP: failed to make connection to backend

[Jim Goodspeed]

I am seeing the following error in my HTTP Apache error_log.  I think this
is OK (I assume the timeout has expired and that it will create a new
connection when it is needed), but I wanted a second opinion.  We are having
a problem with some dropped connections and I think it is either network or
database related, but I want to eliminate the tomcat and apache setup to be
safe.

Thank you in advance for your help.


I have two web servers in front of two tomcat servers - 2.2.10 for the web
servers and 6.0.16 for the tomcat servers.


Error from apache error_log:
[Mon Jan 26 12:00:56 2009] [error] (70007)The timeout specified has expired:
proxy: AJP: attempt to connect to 10.222.4.30:55330 (
noandvtc02b.noandv.btbpo.net) failed
[Mon Jan 26 12:00:56 2009] [error] ap_proxy_connect_backend disabling worker
for (noandvtc02b.noandv.btbpo.net)
[Mon Jan 26 12:00:56 2009] [error] proxy: AJP: failed to make connection to
backend: noandvtc02b.noandv.btbpo.net


My configuration is the following on apache:

    ProxyRequests Off
    ProxyPreserveHost On

    <Proxy *>
        Order deny,allow
        Allow from all
    </Proxy>

    <Proxy balancer://app>
        BalancerMember ajp://server1:8009 route=app-a loadfactor=5
        BalancerMember ajp://server2:8009 route=app-b loadfactor=5
    </Proxy>

    <Location / >
        ProxyPass balancer://app/ stickysession=JSESSIONID
    </Location>


My AJP configuration on each tomcat server is below:

    <!-- Define an AJP 1.3 Connector on port 8009 -->
    <Connector port="8009"
               enableLookups="false" redirectPort="8468" debug="0"
                maxThreads="200" minSpareThreads="10" maxSpareThreads="25"
                acceptCount="100" connectionTimeout="20000"
               protocol="AJP/1.3" />



I have the following jvmRoutes defined on each tomcat server in the
server.xml file:

<Engine name="Catalina" defaultHost="localhost" debug="0" jvmRoute="app-a">
<Engine name="Catalina" defaultHost="localhost" debug="0" jvmRoute="app-b">