On Sep 1, 2012 1:38 AM, "Ed Young" <e...@summitbid.com> wrote: > > Thanks for the reply. > > On Fri, Aug 31, 2012 at 12:10 AM, Igor Cicimov <icici...@gmail.com> wrote: > > On Fri, Aug 31, 2012 at 11:13 AM, Ed Young <e...@summitbid.com> wrote: > >> > >> I've set up a load balancing configuration based on an Apache server > >> and two tomcats Tomcat6A, and Tomcat6B. I'm trying to set it up so > >> that Tomcat6B is a failover server, so if Tomcat6A goes down, Tomcat6B > >> will handle all subsequent requests. > >> > > > > This is a hot standby scenario. IMHO the best is to use mod_jk instead. > > > > Example of mod_jk config for your workers.properties file: > > > > <IfModule jk_module> > > JkWorkersFile conf/workers.properties > > JkLogFile "|/usr/local/apache2/bin/rotatelogs > > /usr/local/apache2/logs/mod_jk.log.%Y%m%d 86400" > > JkLogLevel Debug > > JKShmSize 256 > > JkShmFile logs/jk.shm > > JkMount /* balance1 > > JkMount /jkmanager/* jkstatus > > </IfModule> > > > > but from your post I'm not sure if you have mod_jk installed and configured > > at all. > > No, mod_jk not installed and this Linux installation has a number of > factors that keep me from building and installing mod_jk > No apxs > No APR > Misconfigured corporate rpm repository which keeps me from installing > httpd-devel and thereby pursuing mod_jk. Hopefully this will be > corrected soon. > > My understanding is that mod_proxy replaces mod_jk, but i haven't had > any success getting mod_proxy to work in a failover scenario, so I may > be stuck for now. > > > > > What you want to achive means that when the balancer worker on Tomcat6A is > > in error state, the balancer will redirect the sessions to Tomcat6B. This > > also means though that that user session should exist on Tomcat6B too which > > on other hand means you need to have some kind of session replication > > between tomcat servers. I haven't seen your full tomcat config but hope you > > have cluster set up or the fail over will not work. > > > > I have a cluster set up, but no session replication. My requirement is > that if Tomcat6A goes down, we will lose any sessions, but all new > sessions will failover to Tomcat6B > > The <Proxy balancer://cluster> descriptor below defines my cluster settup, no?
No. Im talking about cluster of tomcat servers not your balancer name. > >> > >> I have two questions: > >> 1. Does mod_proxy use the workers.properties file? It doesn't seem to > >> make any difference what is in workers.properties. > >> 2. How can I set this system up for a failover configuration? > >> > >> This is killing me. I'm using mod_proxy, mod_proxy_balancer, mod_ajp. > >> > >> In the load balancer howto, it specifies the configuration I want by > >> using the workers.properties file, but that file seems to have no > >> effect on the system behavior. I wonder if it was written before > >> mod_proxy became a replacement for mod_jk. > >> _ http://tomcat.apache.org/connectors-doc/generic_howto/loadbalancers.html > >> > >> No matter what I do, if I shut down Tomcat6A, there is no failover > >> behavior. Existing Tomcat6A request fail (expected) and new requests > >> fail with 404. Only the existing Tomcat6B request continue. > >> > >> Header add Set-Cookie "ROUTEID=.%{BALANCER_WORKER_ROUTE}e; path=/" > >> env=BALANCER_ROUTE_CHANGED > >> <Proxy balancer://cluster> > >> BalancerMember ajp://chimps-lb-01.cable.bogus.com:8009 > >> route=Tomcat6A > >> BalancerMember ajp://chimps-lb-02.cable.bogus.com:8009 > >> route=Tomcat6B > >> ProxySet stickysession=ROUTEID > >> </Proxy> > >> > >> ProxyPass / balancer://cluster/ > >> ProxyPassReverse / balancer://cluster/ > >> > > > > For mod_proxy_balancer (if you insist), I would put something like this: > > > > > > <Proxy balancer://cluster> > > BalancerMember ajp://chimps-lb-01.cable.bogus.com:8009 > > route=Tomcat6A > > BalancerMember ajp://chimps-lb-02.cable.bogus.com:8009 > > route=Tomcat6B status=+H > > ProxySet stickysession=ROUTEID nofailover=Off lbmethod=bytraffic > > </Proxy> > > > > This puts Tomcat6B worker in hot backup state and the whole traffic is > > redirected to Tomcat6A. Per my understanding, the above configuration means > > that when the balancer worker on Tomcat6A is in error state, the balancer > > will redirect the session to Tomcat6B which is marked as hot backup . The > > tomcat session replication remark is valid in this scenario too. > > > > I tried this (thanks) and I'm afraid that it does not work. When > Tomcat6A goes down, it does not route new traffic to Tomcat6B Then look at your logs on both sides and check what is not working. > > I wonder if there is anyone who has successfully configured a cluster > failover using mod_proxy? > > > > >> The configuration above alternates between each tomcat as request come > >> in, which is not what I want. > >> > >> I created a workers.properties file in /etc/httpd/conf/, based on the > >> loadBalance Howto, but it does not seem to have any effect on the > >> system. Does mod_proxy use it? > >> > >> worker.list=balance1 > >> > >> # The load balancer worker balance1 will distribute > >> # load to the members Tomcat6A, Tomcat6B > >> worker.balance1.type=lb > >> worker.balance1.balance_workers=Tomcat6A, Tomcat6B > >> > >> worker.Tomcat6A.type = ajp13 > >> worker.Tomcat6A.host = chimps-lb-01.cable.bogus.com > >> worker.Tomcat6A.port = 8009 > >> worker.Tomcat6A.redirect=Tomcat6B > >> #worker.Tomcat6A.lbfactor = 10 > >> > >> worker.Tomcat6B.type = ajp13 > >> worker.Tomcat6B.host = chimps-lb-02.cable.bogus.com > >> worker.Tomcat6B.port = 8009 > >> worker.Tomcat6B.activation=disabled > >> > >> Each tomcat server.xml has > >> <Engine name="Standalone" defaultHost="localhost" jvmRoute="Tomcat6A"> > >> or > >> <Engine name="Standalone" defaultHost="localhost" jvmRoute="Tomcat6B"> > >> > >> --------------------------------------------------------------------- > >> To unsubscribe, e-mail: users-unsubscr...@httpd.apache.org > >> For additional commands, e-mail: users-h...@httpd.apache.org > >> > > > > > > > > > > > > > > -- > - Ed > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@httpd.apache.org > For additional commands, e-mail: users-h...@httpd.apache.org >
