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VWIC-2MFT-T1-D1 Clocking, Slip error, hardware loopback

I am having an issue with a MLPPP point to point bundle with two VWIC-2MTF-T1-DI (4 t1's) and one of the VWICS have errors (CRC, slips, etc) on both ports,(the other pair vwic is clean) I guess I should mention that a hardware loopback test failed; dropped packets with 0x0000 and 0xabcd, 0x1111. I cant find any docs on if this is a known issue or what, at this point I am assuming I have a bad VWIC mod and planning on replacing it. Any ideas?

ISP says it is not providing clocking, so one side is set on all 4 controllers for clocking interal, the other with network clock wic 0 (bad) and wic 1 (good one) all 4 T1's same provider

The vwic 2mft that has errors is configured exactly the same as the one that does not have errors, the only difference is that one of the t1's connected to the wic 0 (w/ problems) is a much older T1 the other three were added later. ISP has tested the line and tech said he detected my equipment wich is configured for ESF B8ZS sent out AMI D4 framing and coding and then went back to esf B8ZS--does that make any sense to anyone--I have had packet loss with a known good hardware loopback plug on both ports of the VWIC in question.

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Re: VWIC-2MFT-T1-D1 Clocking, Slip error, hardware loopback

Hello Paulo,

if you can change the older T1 on the troubled VWIC is a possibility it is disturbing.

the fact that had changed the line code during tests with no config change is enough to say it isn't working well

Hope to help


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