Back-To-Back PRI - Am I Missing something??

Hi! Anyone know if a Back to Back PRI lab configuration is possible with the following hardware:

Router1 - c1760, PVDM-256K-16, VWIC-2MFT-T1, CME
T1 X-Over cable (tested)
Router2 - c1760, PVDM-256K-16, VWIC-2MFT-T1, CME

I see layer-1 connectivity between the PRI, but have been unable to call across.

Router1:
tdm clock T1 1/0 both import onboard internal
isdn switch-type primary-ni
controller T1 1/0
framing esf
linecode b8zs
pri-group timeslots 1-12,24
interface Serial1/0:23
no ip address
encapsulation hdlc
no logging event link-status
isdn switch-type primary-ni
isdn protocol-emulate network
isdn incoming-voice voice
no cdp enable

Router2:
tdm clock T1 1/0 both export line
isdn switch-type primary-ni
controller T1 1/0
framing esf
linecode b8zs
pri-group timeslots 1-12,24
interface Serial1/0:23
no ip address
encapsulation hdlc
no logging event link-status
isdn switch-type primary-ni
isdn incoming-voice voice
no cdp enable

Thoughts???

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Comments

pitviper

I'm all set now - above config works like a charm when I put the crossover cable between the CORRECT T1 ports (had them connected via 1 and not ports 0!!!). Good example of why lab experience with real gear is so beneficial. I looked over the config like 20 times before I located the physical error!!!!

Luckycharms

HAHAHA >>> I laugh because I have done that before with FXSs ports... If you ever mess with High Density FXS/DID cards make sure you test them before assuming they work..

But good for you on finding the problem...

mikej412

pitviper wrote:

I see layer-1 connectivity

But doesn't layer 1 connectivity imply that it's plugged into the correct port?

Oh well -- Layer 0 (user) problems can be the hardest to track down

pitviper

mikej412 wrote:

pitviper wrote:

I see layer-1 connectivity

But doesn't layer 1 connectivity imply that it's plugged into the correct port?

Nah, hardware level, green light on the VWICs

I'll just have to train myself to think right to left I guess!

mikej412

pitviper wrote:

isdn protocol-emulate network

I still think people forgetting this is the #1 issue when doing back-to-back PRI.

Somewhere in the distant past I guess I must have plugged into the wrong T1 port -- I always use a loopback plug to test -- and see which port comes up