== Another aphorism of system administration

> Noticing when something shows up is easy; detecting when it goes away
> is hard.

Like all aphorisms, this has exceptions. And if you want to see it that
way, it's a corollary of an [[earlier aphorism SysadminAphorismII]].

(An aphorism brought to mind as I contemplate our DHCP configuration
files and wonder just how many of those Ethernet addresses are currently
mouldering in a dump somewhere.)