For a quick and dirty summary I like to use VADSU.
So from expert mode, enter DIS-VADSU;
You will get a few tables. One of which looks like this:
+==============================================================================+
| ALARM GROUP: PERIPHERAL SWU ALARMS |
+===+=====+=====+=====+=====+=====+=====+=====+===+==+==+======================+
|AL.|THRS1|THRS2| ERR.|ERRS.|TOTAL|TIME1|TIME2|TME|PR|HW| NAME |
|NO.|IN % |IN % | ABS.|IN % | |[SEC]|[SEC]|[H]| |CO| |
+---+-----+-----+-----+-----+-----+-----+-----+---+--+--+----------------------+
| 0| 5| 10| 0| 0| 6| 900| 300| 0| 0|SU|CO TRUNK/EXCH LINE |
| 1| 5| 10| 0| 0| 46| 900| 300| 0| 0|SU|TIE LINE |
| 2| 5| 10| 0| 0| 14| 900| 300| 0| 0|SU|MULTIPLE DEVICES |
| 3| 10| 20| 1| 4| 25| 900| 300| 0| 0|SU|ANALOG VOICE DEVICES |
| 4| 10| 20| 3| 2| 125| 900| 300| 0| 0|SU|DIGITAL VOICE DEVICES |
| 5|DEACT| 1| 0| 0| 0| 0| 600| 0| 0|SU|ATTENDANT CONSOLE |
| 6| 5| 10| 0| 0| 0| 900| 300| 0| 0|SU|CO/EXCHANGE DATA LINE |
| 7| 5| 10| 0| 0| 0| 900| 300| 0| 0|SU|TIE DATA LINE |
| 8| 1| 50| 0| 0| 0| 600| 600| 0| 0|SU|BASE STATION |
| 9| 0| 90| 0| 0| 0| 600| 600| 0| 0|SU|LOGICAL DEVICES |
| 10| 25| 50| 0| 0| 0| 600| 600| 0| 0|SU|TFS LINE |
| 11| 25| 50| 0| 0| 0| 600| 600| 0| 0|SU|VMS LINE |
| 12| 5| 10| 0| 0| 0| 900| 300| 0| 0|SU|APSE |
| 13|DEACT|DEACT| 0| 0| 1| 0| 0| 0| 0|SU|OTHER DEVICES |
| 14| 10| 90| 0| 0| 0| 600| 600| 0| 0|SU|DATA DEVICES |
| 15| 1| 50| 0| 0| 0| 600| 900| 0| 0|SU|CONVERSION RESOURCES |
+===+=====+=====+=====+=====+=====+=====+=====+===+==+==+======================+
This will tell you how many copper trunks you have BUILT, How many T1 channels are defined (TIE Line), How many analog and digital devices you have, and a few other things you might use that I don't.
A couple of notes:
I don't know if Digital Devices includes IP phones - I never bothered to physically count and chack.
I don't know what "Multiple Devices" are.
The number of devices under the "Total" column includes all trunks/phones you have built in the system regardless of whether they are connected (not the number of ports the system is equipped for, but the ones that are in use). For the digital devices the error count will indicate how many devices are disconnected; Analog ports have no way to know if the device is disconnected (unfortunately) so will not show an error unless the port is in defect.
Another function I find useful is DID-DIMSU:ALL,; WHich can tell you all sorts of cool things like how many PU groups you have, how many speed dial numbers, total stations, etc....