Nortel 2430 router & leased line setup help req'd

[LAV1]

Hi there
I need to set up two 2430 Nortel routers across a 512k leased line. We prev. had the routers set up back-to-back (cable connection) and everything was OK. Now that we're testing across the proper telco leased line, nothing happens. Do any of you guys have a sample config or some "must check" items we can look at?

 

[Jynxx]

Depends...what are your leased lines? Frac T1's or ISDN lines through a mux?

 

[LAV1]

Hi Jynxx,
It's ISDN lines through a MUX/NTU at 512k. AFAIK the clock src. should be ext, but at what speed do I then specify it? Same as line spd? Also, if the WAN protocol is set to std, the router shows the serial side to be up, but the moment it is set to PPP, the status changes to down.

 

[Jynxx]

Honestly, it's been a while since I configured anything for ISDN.

Are you setting up your leased lines to be the primary constant on circuit, or a backup to another circuit or dial-as-needed?

I have actually never set one up as a primary constant on connection.

I have set them as backup circtuis before. If I remember correctly, I specified the circuit as PPP, with speed set to the line speed of the ISDN lines muxed together, then created a demand pool and a PPP demand circuit...with it set as a hot standby (pointing to the circuit that needs to be backed up) and doing simple chap authentication on each end.

I also set both sides IP to "un-numbered" 0.0.0.0/0.0.0.0

 

[LAV1]

Hi Jynxx, it is an always-on 512k circuit. Here is where I feel really stupid - after battling for a whole day, doing loopbacks and getting the telco to double-check their lines, I eventually found that the (brand new!) Nortel 7224 interface cable from the 2430 to the telco's NTU was faulty. It is some consolation that a colleague and two other local Nortel specialists failed to think of this. Murphy strikes again - the last thing you check is the problem! Anyway, many thanks for your advice and willingness to help.

 

[Jynxx]

Not sure what kind of mux you are using, but we have used Adtran 512's and I needed either a 7159 or a 7220 cable to hook to them. Also the same cable that I use to go directly to a DL3800 as well as Verilink CSU's...all the same. Never tried a 7224 before.