My compaany has two locations. We have had them connected via ISDN. It has been working for the past 4 years, but all of the sudden (last Friday) the connection went down in the middle of the night. We have been troubleshooting for days with absolutely no luck !!! Our Telco Company (Telus) says that the ISDN line tests fine on both sides.
Our Setup is as follows:
Cisco 4000 Router--> Adtran ISU128
-----(over the ISDN line)------>
Adtran ISU128---> Cisco 2501 Router.
We have always had a Multilink PPP (MPPP) Link across this network.
As near as I can tell, I think that the configuration of one or both of the routers has been compromised. The 2501 seems to be acting as the dailer in our case. I have double checked the modems on both sides, and their config. looks correct.
I was wondering if there is anyone out there that knows the correct setup and configuration for the two routers (4000 and 2501) so we can re-input the config and start from scratch.
Any and all suggestions would be welcome.
Thank you in advance.