I finally got access to the test server logs, and found these lines particularly interesting: | (ScannerThread) WARN [FileURLLister] Could not list directory '/jboss/server/default/farm', reason unknown | (ScannerThread) WARN [FileURLLister] Could not list directory '/jboss/server/default/deploy', reason unknown | (ScannerThread) DEBUG [MainDeployer] Undeploying file:/jboss/server/default/farm/some-app.ear | (ScannerThread) DEBUG [MainDeployer] Undeploying file:/jboss/server/default/deploy/some-other-app.ear | And so on... Spontaneous app undeployment due to the ScannerThread not being able to read the deploy and farm directories, possibly due to the load put on the server. So my conclusion is that CPU starvation is causing the undeployment issue. This is not a problem as we will never hit this kind of load when live, but still looks like odd behaviour and something that might be addressed more gracefully (i.e. issue warning when not able to read farm/deploy dirs, but don't undeploy by default). As this is not directly related to the ResourceAdapter, feel free to move this thread to a more suitable location. I will now investigate if this is something worth raising as a bug. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4025428#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...