Adding 2nd point to point T1

[bigdog175]

I'm upgrading a headend router to a 3640 w/ 1 ptp T1 working adding a 2nd ptp T1 to connect another remote office. What am I missing? I have the setup running in a lab wanted to test throughly before installing. 3640 w/ 1FE2W & 2xWic T1's connect back to back adtran tsu 120's w/router mods I can get either of the circuits up on it's own but can not get both circuits up at the same time. i.e. S0/0 up and stable when I try to plug in S0/1 it stays up for 20 sec and then down and the up again for 20 sec. But if I reload with S0/1 connected and the S0/0 disconnected it goes up and stays stable but when I plug in the cable to S0/0 then that circuit goes up and down. I have timing on the S0/0 set to line and timing on S0/1 set to internal and have also tried with both timings set to line same results. I have not worked with multiple T's in cisco box before in an adtran Atlas unit I know I just pick one of the T1's as the timing source is there a way to do that in cisco router, we will also be adding two more T1's at least. Any thoughts or input is welcome/ appreciated.

 

[Warcorp]

What version of IOS is running on the 3640?

 

[bigdog175]

I'm runnig 12.0(7)XK1

 

[Warcorp]

Timing only affects the physical T1 it is associated with so timing is probably not the issue. I had a similar problem on a 3640 with a hssi port. The eventual solution was to replace the IOS on it (no one could explain why it was doing what it was doing). We moved it to a new version of IOS and the problem went away.

 

[tbilan]

You'll have better luck with answers if you post the configs. I'm unfamiliar with Adtran equipment but in general if you have 2 pair of CSU/DSUs and S0 works fine by itself and S1 works fine by itself it sounds like an IOS bug.

Tom Bilan
TJBA, Inc.
CCNP, CCDP, MCSE & CNE