As an odd consequence of being so stable. I find our FreeBSD boxes are always running EOL software. Then the struggle starts of not wanting to upgrade because the box works perfectly fine.
This one for example is being upgraded to 10.0-RELEASE via a quick stop at 9.2-RELEASE:
data01# uname -a
FreeBSD data01 9.0-RELEASE FreeBSD 9.0-RELEASE #0: Tue Jan 3 07:46:30 UTC 2012 email@example.com:/usr/obj/usr/src/sys/GENERIC amd64
5:03PM up 878 days, 19:13, 2 users, load averages: 0.74, 0.46, 0.37
This box and it's sister are being left alone:
sys01[~]% uname -a
FreeBSD sys01 8.1-RELEASE FreeBSD 8.1-RELEASE #0: Mon Jul 19 02:55:53 UTC 2010 firstname.lastname@example.org:/usr/obj/usr/src/sys/GENERIC i386
5:08PM up 1396 days, 18:39, 1 user, load averages: 0.00, 0.00, 0.00
What's amazing is that their uptime would probably be in the six to seven year range if it wasn't for a datacenter move.