External calls suddenly disconnected (bothincoming&outgoing)

[cavagnaro]

The Telco will always claim that it is not their problem, is this problem from a new installation or one that have being working?
If new, check your PRI configurations and clock synchro.
If old, tell the Telco guys to run a BER test on the customer PRI, claim that you have exhausted all your alternatives (even when you haven't), if the BER test (running for a descent period of time) is ok then think on changing PRI board to discard.
Also analyze if the sets that present the problem belong to a unique board or to many. If unique consider also changing the board (or swapping at least) to discard a board issue. If you swap the problem should trasladate to the new sets on that board.

[johnson_tiam]

oh.. i think the ISDN digital trunk from telco MDF.
sorry..my mistake.
i'm not sure with the digital set,
but the thing is it also occur on analog set.
what do you suggest?

Many Thank's