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MGX end VPI/VCI error

Dear All,

There is IMA keep bouncing issue, telco test the circuit all the way to smart jack, there is no error, we replaced the router as well, however, two ATM links still flapping. When I check MGX end, there is VPI/VCI error keep increasing, anyone knows what's this error indicate?

thank you,

  • WAN Routing and Switching

Re: MGX end VPI/VCI error


Could you please clarify what your network topology is?

From what you are saying, I suppose that you have something like that:


VPI/VCI error means the MGX end received cells that had an invalid value for the VPI, VCI ATM cell fields. This could be a misconfiguration (i.e. the router sends invalid cells towards the MGX) or could be just a side-effect of the problem you are experiencing (i.e. link is bad, keeps flapping, some headers can become corrupted under those circumstances).

Since you replaced the router during the troubleshooting procedures, make sure the VPI/VCI's on the new router side are valid and in accordance to what the MGX expects. You still have to check your circuit further, because I think a VPI/VCI error would not be a cause for subsequent link flaps.

There are 2 circuits bundled into this IMA. Have you had the telco check them both? Maybe only 1 of the 2 circuits in the bundle is problematic. Try to find which one by the process of elimination (i.e. remove them both, then add only one of them, wait a bit and see if this one keeps flapping, repeat similar procedure with the other one).

Kind Regards,