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Due to the limitation with mod_jk for autoscaling configurations, we took a look at mod_proxy Instead of using AJP (mod_jk) protocol we can use the HTTP protocol and with this approach we do not use Apache for the actual load balancing or session stickiness. Instead all requests from the Apache server are forwarded to the application tier ELB (say it runs at HTTP port 8080) and the ELB does load balancing as well as maintains session stickiness. The Apache httpd.conf configuration for the same is mentioned below. LoadModule proxy_module        modules/mod_proxy.so LoadModule proxy_http_module   modules/mod_proxy_http.so ProxyPass /img ! ProxyPass /images ! ProxyPass /css ! ProxyPass /media ! ProxyPass / http://internal-RCCL-AppTier-ELB-722360436.us-east-1.elb.amazonaws.com:8080/ ProxyPassReverse / http://internal-RCCL-AppTier-ELB-722360436.us-east-1.elb.amazonaws.com:8080/ § Pros: ...

Part 1 gave the overall deployment picture .   If the application requires session stickiness at the Tomcat tier, i.e. if some user details are stored in the HTTP Session and you don't enable session replication across Tomcats. The solution is that the Elastic Load Balancer (ELB) maintains the sticky session using it’s own cookie called AWSELB. For ELB sticky session configuration see http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/using-features.managing.elb.html In case there is an external ELB (Apache tier) with cookies stickiness set, it will over-ride the internal ELB (Tomcat tier). The stickiness cookie is always named AWSELB, hence the external ELB will overwrite the cookie from the internal ELB. One option here is to set the Tomcat tier ELB with "Application Generated Cookie Stickiness" with value JSESSIONID so it will follow the Application cookie and maintain sticky sessions.   In case sticky session is not enabled on the application ti...

The cloud proposition is attractive because of the ability to scale up or down to meet workload demand almost instantaneously and to utilize efficiencies in the services delivery model. The rationale of using and paying for only what you need, when you need it is a very compelling business justification.   This post and the next few ones describes the various options and features available when a web application is deployed on the AWS cloud infrastructure using Apache HTTP Web Server and Apache Tomcat application server. This document deals more with options available to maintain sticky sessions and application persistence.   This is based on a recent project where we are deploying with Apache 2.4 and Tomcat 7.0.x   First some basic terms     AWS Glossary   ·                      Amazon EC2 is hosted in multiple l...

Music albums that I've liked over the last few months: Radical Face - love this album The Family Tree: The Branches - reminds me of Bon Iver and The Verve The National - Trouble Will Find Me Of Monsters and Men The Secret Life of Walter Mitty - OST - Jose Gonzalez has a superb song titled Step Outside Pearl Jam - Lightning Bolt Aside on Bon Iver's Holocene - which was part of the OST for Cameron Crowe's "We Bought a Zoo" - the lyrics and tune remind you of vast open white wilderness (ignore the geological meaning ) - which reminds me of what a Vanilla Sky would look like - which is another of Cameron Crowe's films.

My Galaxy Core hangs all the time. I uninstalled all downloaded apps and also I did a factory reset, but that also didn’t help. Some googling led me onto this post on XDA developers. If you want more info (and know more about the risks), go to the XDA forum and read the whole thing. Temporary Fix So the steps are install Dummy File Generator  (DFG) on your phone. This app can populate your entire internal memory and SD-card memory with dummy data. I completely filled the internal memory with that tool. After that go back to the tool and choose "Delete" of all the dummy files. You will get a warning message that memory is nearly full. Whatever you do - do not reboot in between this, because the phone won't reboot after that. If the DFG hangs when trying to delete dummy files, then go to Application Manager > Dummy File Generator > Clear Data. After this there will still be the odd freeze but not as severe as before (m...