I will be doing some maintenance activity today that may result in very brief interruptions (less than one minute) and then just after midnight rebooting servers to make software updates go into effect, particular an update to glibc which is a standard library used by virtually all C programs (which is almost everything).
The reboots will take place between 12:05AM and 12:30am on July 14th, 2013.Those of you who have background tasks running on the shell server that do not restart automatically will need to restart them after the reboots.