I'm using Tomcat 5.5.9 on Windows Server 2003, JDK 1.5.0_04, IIS 6.0, with the
JK 1.2.14 isapi_redirector.dll.
I've been trying to track down a problem whereby all of the web apps under our
Tomcat instance are seeming to stall. There's no indication of any problems in
the Tomcat logs themselves. I suspect IIS is unable to forward requests to
Tomcat. I either have to recycle the IIS worker process or restart Tomcat to
resolve the problem.
Here's what I'm seeing with netstat (port 8008 is my AJP 1.3 port):
Z:\>netstat -a -n | grep 8008
TCP 0.0.0.0:8008 0.0.0.0:0 LISTENING
TCP 147.92.2.137:2871 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:2915 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:2944 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:2965 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:2969 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:3019 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:3034 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:3039 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:3041 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:3060 147.92.2.137:8008 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:2871 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:2915 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:2944 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:2965 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:2969 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:3019 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:3034 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:3039 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:3041 ESTABLISHED
TCP 147.92.2.137:8008 147.92.2.137:3060 ESTABLISHED
Every time the stall has happened, I have noticed that there are always exactly
ten connetions between IIS and Tomcat (they're on the same server). Everything
works fine until we reach this point.
In my JK log, I'm seeing things like this:
[Wed Aug 24 14:10:57 2005] [error]
ajp_connection_tcp_get_message::jk_ajp_common.c (961): Can't receive the
response message from tomcat, network problems or tomcat is down
(147.92.2.137:8008), err=-54
[Wed Aug 24 14:10:57 2005] [error] ajp_get_reply::jk_ajp_common.c (1503):
Tomcat is down or refused connection. No response has been sent to the client
(yet)
My workers.properties looks like this:
worker.list=ajp13a
worker.ajp13a.port=8008
worker.ajp13a.host=www.bvu.edu
worker.ajp13a.type=ajp13
cachesize=20
cache_timeout=600
recycle_timeout=300
And here's the AJP connection defininition from my server.xml:
<Connector port="8008"
maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
enableLookups="false" redirectPort="443" debug="5"
connectionTimeout="20000"
protocol="AJP/1.3"/>
Any idea what might be happening? It sure looks like I'm hitting some kind of
10 connection limit somewhere, but I can't seem to figure out where.
