You will need to reconfigure the pri-group command near the top of the configuration. You will see a line similar to this below:
controller e1 1/0
You will need to look at the line shortly after that which should start with:
pri-group timeslots 1-31
It may have some other options after the 1-31 command which you will need to note before changing this. You can then go ahead and enter the new command with the new timeslots used (1-8).
Hope this helps
I have done a debug isdn q931 and it doesnt do anything, if I ping a remote router, nothing happens at all, is there anything i can check to see if the isdn lines are up ?
sh isdn status
Here is a doc for Layer 1
This is for layer 2
Have you tried removing 16 to see if it makes a differenece?
Here is a doc on Configuring ISDN PRI
It say's 16 as this is the D-channel for signalling
Usae the show ISDN ser command which will show the current status of the channels on the PRI