The JVM DNS cache "security decision to prevent rebinding attacks" bit me once. I had changed an IP address for one of my systems. A "vendor" I was working with claimed one of their servers could no longer reach mine. I must have a routing problem on my network. This went on-and-on for a week until I finally talked them through running tcpdump and sending me packet captures, then another week to get them to restart their service...
The JVM DNS cache "security decision to prevent rebinding attacks" bit me once. I had changed an IP address for one of my systems. A "vendor" I was working with claimed one of their servers could no longer reach mine. I must have a routing problem on my network. This went on-and-on for a week until I finally talked them through running tcpdump and sending me packet captures, then another week to get them to restart their service...