I learned that if you have a polycom system and you are trying to troubleshoot why international ISDN video calls can not come in or out, it will take 2 weeks of back and forth finger pointing between your PBX vendor and your PRI provider before they finally figure out that A: maximum digits needs to be changed and B: the PRI vendor has a PIC code sending all international D-channel traffic over to MCI because they have no terminating agreements, and that they only applied that PIC code to 1 of your 2 PRI/trunk groups, so that when it hit the first PRI/trunk group and found it busy, and rolled to the next, there was no PIC code to route it to MCI.
and also C: certain polycomm and picturetel units will not communicate with each other. even though i'm pretty sure polycomm ended up aquiring picturetel.
That was a joyous task.
I also learned that even though the documentation says you can use ESX based VMware guests to create a riverbed RSP win2k3 package so you can have a virtualized win2k3 server on your branch office steelheads (gonna be print servers, EPO and WSUS repositories, i hope), that they are actually full of sh!t and only VMware server 2.0 guests will work to make the RSP package.
Dammit, MONOLITHIC disk --

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i also am continually reinforced taht riverbed has one of the best support orgs out there, and that i can forgive one piece of bad info in one of their docs for the other 30,000 times they have pulled my ass out of a firey inferno.
it was a day of culminations today.
i also learned that if you go to boston during the thanksgiving weekend and drink "beer punch" at cambridge commons with your cousin and his lackeys, you will come back with the cruddiest sinus infection ever. swine flu got nothing on this crap. and no sick day in sight.