Thanks Guido ! On Thu, May 11, 2017 at 12:02 PM, Jäkel, Guido <g.jae...@dnb.de> wrote:
> Dear Adhavan, > > I think this is quiet normal, because the browser clients "in front" will > reuse connections (using keep-alive at TCP level) but an in-between load > balancer may be not work or configured in this way and will use a new > connection for each request to the backend. > > Then, you'll see a lot of sockets in the TCP/IP closedown workflow between > the load balancer and the backend server. Pleases refer to TCP/IP that the > port even for a "well closed connection" will be hold some time to handle > late (duplicate) packets. Think about a duplicated, delayed RST packet - > this should not close the next connection to this port. > > Because this situation is very unlikely or even impossible on a local area > network, you may adjust the TCP stack setting of your server to use much > lower protection times (in the magnitude of seconds) and also adjust > others. And at Linux, you may also expand the range of ports used for > connections. > > BTW: If you have a dedicated stateful packet inspecting firewall between > your LB and the server, you also have to take a look on this. > > > Said that, one more cent about the protocol between the LB and the Tomcat: > I don’t know about HTTP, but if you use AJP (with mod_jk) you may configure > it to keep and reuse connections to the Tomcat backend(s). > > Guido > > >-----Original Message----- > >From: Adhavan Mathiyalagan [mailto:adhav....@gmail.com] > >Sent: Wednesday, May 10, 2017 6:32 PM > >To: Tomcat Users List > >Subject: CLOSE_WAIT between Application (Tomcat) and Apache HTTPD > > > >Team, > > > >Tomcat version : 8.0.18 > > > >Apache HTTPD version : 2.2 > > > > > >There are lot of CLOSE_WAIT connections being created at the > >Application(tomcat) ,when the traffic is routed through the Apache HTTPD > >load balancer to the Application running over tomcat container. This leads > >to slowness of the port where the Application is running and eventually > the > >application is not accessible through that particular PORT. > > > >In case of the traffic directly reaching the Application PORT without > HTTPD > >(Load balancer) there is no CLOSE_WAIT connections created and > application > >can handle the load seamlessly. > > > >Thanks in advance for the support. > > > >Regards, > >Adhavan.M >
