Thanks Rainer, now I know where to direct the troubleshooting efforts. Seems I have some networking issue.
On Thu, Oct 13, 2011 at 6:30 AM, Rainer Jung <rainer.j...@kippdata.de> wrote: > On 13.10.2011 06:16, Jorge Medina wrote: >> I have Apache (2.2.20) in front of a single Tomcat (6.0.32) instance >> using mod_jk (1.2.31) with the AJP protocol. >> I am getting errors like the sample below frequently (a few hundred >> times a day). The server does not have a heavy load, it serves about >> 150 req/minute and average response time of 200 ms) >> >> [2011-10-12T23:27:00.644-0400] [20239:27] [info] >> ajp_service::jk_ajp_common.c (2543): (S1) sending request to tomcat >> failed (unrecoverable), because of client read error (attempt=1) >> [2011-10-12T23:27:00.654-0400] [20239:27] [info] >> service::jk_lb_worker.c (1388): service failed, worker S1 is in local >> error state >> [2011-10-12T23:27:00.655-0400] [20239:27] [info] >> service::jk_lb_worker.c (1407): unrecoverable error 400, request >> failed. Client failed in the middle of request, we can't recover to >> another instance. >> [2011-10-12T23:27:00.655-0400] [20239:27] [info] jk_handler::mod_jk.c >> (2620): Aborting connection for worker=wlb >> >> >> a) Could I get some help to interpret the messages above? > > The browser or whatever is talking to your webserverstarted a request, > but didn't send the full request. Most likely it took too long to send > the full POST body, but it could also happen during other requestread > phases. > >> b) What is being referred as "Client" ? The client originating the >> request or does mod_jk calls "Client" my Tomcat instance? (I guess I >> don't know if mod_jk establishes the connection to Tomcat or if Tomcat >> is establishing the channel to mod_jk) > > Client is the web server client, e.g. the browser or similar. > >> c) Messages are logged as [info] rather than warning or errors...why? >> Should I not be concerned about these messages? > > Because typically there's nothing to fix on the server side. Only if > this happens very frequently, you might have a network problem, or a lot > of users with bad network connections. > >> d) If that is a symptom of a problem, how do I fix it? (In fact, I am >> being reported that clients of my app are timing out waiting for a >> response, but my application logs don't have any indication of >> receiving the request, so I am trying to find out if the message above >> is an indication that the problem occurs in the Tomcat Connector, and >> therefor my web app running in Tomcat never got the request at all) > > It is a message concerning only communication between client and web > server, no communication between web server and Tomcat is involved in > the problem. If you want to debug, concentrate on the communication > between client and web server and try to understand the request details > for which it happens (GET or POST or something else; Content-Length set > or chunked encoding for the request used etc.). You might need to sniff > traffic. > >> === workers.properties >> >> workers.tomcat_home=/opt/greatapp/tomcat >> workers.java_home=/opt/jdk/jdk6.0 >> ps=/ > > The above three are useless garbage. > >> worker.list= wlb, jkwatch >> worker.wlb.type=lb >> worker.wlb.balance_workers=S1 >> worker.wlb.max_reply_timeouts=3 >> >> worker.jkwatch.type=status >> worker.jkwatch.read_only=True >> worker.jkwatch.mount=/private/admin/watch/jk >> >> worker.S1.type=ajp13 >> worker.S1.host=localhost >> worker.S1.port=6009 >> worker.S1.lbfactor=1 >> worker.S1.connection_pool_timeout=600 >> worker.S1.socket_keepalive=False >> worker.S1.socket_timeout=15 >> worker.S1.reply_timeout=300000 >> worker.S1.recovery_options=27 >> >> >> === uriworkermap.properties >> >> /myapp=wlb >> /myapp/*=wlb >> /private/admin/watch/jk=jkwatch > > Not too bad :) > > For improvements look at the full exampleconfig contained in a recent > source download of mod_jk.But as said: the problem is not with > communication web server to tomcat. > > Regards, > > Rainer > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > > --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
