I have a UC520 system with a PRI. How do I get a fax machine connected and configured to support inbound and outbound faxes?
The PRI has 100 DIDs and '99' is going to be used for the fax. The fax is plugged into FXS port '0'.
voice service voip
modem passthrough nse codec g711u
dial-peer voice 1 pots
That's about it. You will need to adjust your 'port' command to which 'voice-port' it corresponds to, like 1/0, 0/0/0, etc.
Make sure 'show controllers t1' doesn't have any slips/errored seconds.