I can periodically look in sysctl.conf and see that my echo_ignore_all and echo_ignore_broadcast variables have been reset to 1. This doesn't seem to be associated with a network restart or computer reboot, and in fact, are fixed by either after I've re-edited this file.
(to see exactly what I'm talking about)
# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1
I'd like the ignore_all variable to stay set at zero for now while I'm troubleshooting my network ... so I can ping this box from others. Somewhere, somehow, however ... and I suspect shorewall ... this variable is reset to 1, and suddenly ... no ping! I haven't witnessed an exact timing on this yet, but it seems to be on the order of hours (one or a few). Most recently, I changed this to zero and noticed the machine was unpingable about 2 hours later.
Anyone know of a cron or structure that gets set up to rewrite this file?