Everyone's favorite message: Serial x/x is up, Line Protocol is Down

Just got my 3640 router in along with my NM-4A/S and NM-1FE1R2W, so I decided to give my first attempt at router on a stick. I previously had two 2501s connected back to back with my crossover serial cable with no issues. I'm now taking one of the 2501's and connecting it to the 3640 and I cannot seem to get an up/up.

Tried PPP and HDLC encapsulation (making sure that both routers were using the same encapsulation), no dice. When I do a debug ppp packet, each router sends LCP messages, but does not receive them. Am I missing something here, or should I talk to the ebay seller I got this from? Thanks!

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Comments

msteinhilber

Did you set the clock rate?

Agent6376

I did, sorry. Forgot to add that in there. Clock Rate was set at both 4000000 and 2000000. This was done on the DCE side of the connection by using show controller serial x/y and verifying that the right side of the cable was locally connected.

kalebksp

Agent6376 wrote: »

Clock Rate was set at both 4000000 and 2000000.

Try setting that lower, maybe 64000.

Agent6376

Thank you both gentlemen, I guess this is why using real equipment helps. I doubt I would have had an issue with my previous configuration in a simulation.

captobvious

FYI

Here are the features of the 4-port (NM-4A/S) and 8-port (NM-8A/S) asynchronous/synchronous (async/sync) network module:

It has four or eight async/sync ports.
It uses Cisco 60-pin "5-in-1" connectors (same as Cisco 2500 and Cisco 7000).
It uses the same cabling as Cisco 2500 and Cisco 7000.
The maximum speed is 115.2 kbps for async, 128 kbps for the sync external clock, and 125 kbps for the internal clock.

Understanding 4- and 8-Port Async/Sync Network Modules