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New Member

Frame Relay Fractional T1 (56k) Config Problems

Perhaps my inexperience is showing, but I'm having some trouble configuring two 1721 routers to communicate and route over a 56k leased line, which I have been told is set for frame-relay. Both routers are installed with a fractional T1 DSU/CSU wic. I've looked through the old configuration walkthroughs, but they all assume installation of a 56k wic and many commands are simply not accepted by the IOS.

Basically, I believe I can telnet into each machine and configure the local IP's just fine, but before I send these routers to their remote locations, I want to make sure they'll plug in and work when they get there. It's probably asking a lot, but can someone help me with a condensed walk-through?

Also, I've noted that the online walk-throughs refer to a line clock to configure speed; as I have both routers with me now, and no access to the actual line, is there a way to hard wire the 56k speed into them?

  • Other Network Infrastructure Subjects

Re: Frame Relay Fractional T1 (56k) Config Problems

Check this link, it should help you out on configuring the 56k line properly.

You should configure one end with clock source as LINE and the other end to have clock source as INTERNAL.

I would suggest you to install a modem at the remote site (if you can get an analog modem) and that way you can dial into it, if anything has been misconfigured, and the line doesnt come up.

New Member

Re: Frame Relay Fractional T1 (56k) Config Problems

you need different wics, there is a 56k wic, a frac t1 uses the same pins as a t1, 1,2,4,and 5. While a 56k leased line uses 1,2,7, and 8. You will never get them to talk using the frac t1 wic.

New Member

Re: Frame Relay Fractional T1 (56k) Config Problems

I had wondered about this. The hardware actually came from a different manufacturer than the leased line. This has turned into something of a consulting nightmare. Also explains why some commands aren't recognized by the service module.

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