RE: "mod_proxy_ajp" | errors (Apache Users)

Hello, Holger.

I posted the message you referenced, and I still do not have any solution for it.

You might try posting to the tomcat-users, users@xxxxxxxxxxxxxxxxx since there’s a Tomcat interaction at work.

Perhaps another person asking will give someone an Ah Ha, though probably not today, at least in the US.

They’ll be too drowsy from overconsumption of roast turkey and root vegetable carbohydrates. ;-)

Take care,

David Dabbs

From: King Holger (CI/AFP2) [mailto:Holger.King@xxxxxxxxxxxx]
Sent: Thursday, November 25, 2010 12:40 PM
To: 'users@xxxxxxxxxxxxxxxx'
Subject: "mod_proxy_ajp" | errors

Hi all,

when using "mod_proxy_ajp" of Apache2 2.2.16 in combination with two Apache

Tomcat 6.0.29 servlet containers, we often see the following entries within the

Apache2 error log of the virtual host:

[Thu Nov 25 16:17:26 2010] [error] ajp_read_header: ajp_ilink_receive failed

[Thu Nov 25 16:17:26 2010] [error] (120006)APR does not understand this error code: proxy: read response failed from 10.35.32.241:8009 (rb-wcmstc2.de.bosch.com)

[Thu Nov 25 16:17:26 2010] [error] [client 10.35.32.123] proxy: error processing end, referer: https://xxx.dot.com/<context_root>/workflow/dialoges/tasks3.jsp?refresh=1

When looking in the central Apache2 error log, we see:

[Thu Nov 25 16:17:26 2010] [error] (70007)The timeout specified has expired: ajp_ilink_receive() can't receive header

Additionally, we sporadically see connection switches from one Tomcat

to the other without any understandable reasson (here from "rb-wcmstc2" to "rb-wcmstc1"):

10.35.32.123 - - [25/Nov/2010:16:17:31 +0100] "POST /servlet/ClientIO/5cmxicinliar/s6/234 HTTP/1.1" 500 1255 "-" "Jakarta Commons-HttpClient/3.1" "

JSESSIONID=68BE78C5C6A2B9756CED86543095C221.rb-wcmstc2" "68BE78C5C6A2B9756CED86543095C221.rb-wcmstc2" "JSESSIONID=C9F5C78771552AF9C15F1D0064099948.

rb-wcmstc1; Path=/" 4784

Might the below timeout be set to short (in combination with the aboe "timeout" error log entry)?

The current "mod_proxy_ajp" configuration looks like this:

# One tomcat node has been outcommented due to the following ticket: Help-20100510-651

BalancerMember ajp://rb-wcmstc1.xxx.dot.com:8009 loadfactor=100 retry=10 route=rb-wcmstc1

BalancerMember ajp://rb-wcmstc2.xxx.dot.com:8009 loadfactor=100 retry=10 route=rb-wcmstc2

ProxySet stickysession=JSESSIONID|jsessionid

ProxySet lbmethod=byrequests

ProxySet scolonpathdelim=On

#ProxySet nofailover=On

ProxySet timeout=45

</Proxy>

Or is there a bug available within the "mod_proxy_ajp" module of Apache2 (details see: http://www.mail-archive.com/users@xxxxxxxxxxxxxxxxx/msg84118.html)

Should we switch to "mod_proxy_http"?