Thank you Stefan, Johann, and the community for making the switch from mod_Webobjects.so adaptor to the built-in Apache mod_proxy module.

It helped us out this week to dig up Stefan’s 2015 video presentation on this topic, utilize the ERXApplication cookie generation, and the migration tab in Java Monitor.

The reason for us to make the switch was because Apache had become unstable. It was having numerous segmentation faults. We were using the latest available Apache 2.4.x for Amazon Linux along with freshly compiled from source WO Adaptor taken from latest WOnder repo. Whenever httpd wet-the-bed, we’d lose communication with an app instance. It seems there was no rhyme or reason to what was causing it to crash. It did seem that when we downloaded user files (passed from disk to web browser through fileInputStreams) that we’d be more likely to see a segmentation fault anywhere from 5 to 7 request-response loops later (navigating the app, clicking links). File sizes ranged from somewhat small like 4 megs up to about 250 megs.

It was almost as if the WO adaptor was getting corrupted. Apache would give errors about unreadable headers that looked like a stream of binary data and then shortly after segmentation fault.