In big companies, 95% of apps are still old school: firewall -- load balancer -- 5 front ends -- 3 back ends -- two database servers. And the people who develo

In big companies, 95% of apps are still old school: firewall -- load balancer -- 5 front ends -- 3 back ends -- two database servers. And the people who developed most of these apps left these companies long time, what these companies have bunch of managers and some developers who maintain that code. People of this kind are extremely conservative, because they are not in a position to fix major issues if something goes wrong--esp new architecture. So, they want to lift as is to aws. A decade ago, I was involved in physically moving three solaris servers that were running un-supported BEA weblogic instances. When I powered on these three servers on a different rack, weblogic cluster failed. No IP change, just moved machines to free up racks in one row. And the people who developed the app, and the dev architect behind it were so mad at us. In the end, they gave up on that app. That's how it goes.