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New Member

ADSL Virtual-Interface 2 Drops

Guys and Gals, Help Please !! This is driving me slightly crazy.

I have a client with a 2Mbps PSTN ADSL line which keeps having intermittent problems.

The physical line stays up but the Virtual-Interface 2 drops and the only way to cure the problem is to re-boot the router. This happens 2 to 3 times a day.

At first I thought it was the router so we removed the SOHO97 and purchased a new 857 running 12.4 (sorry don't have exact image details at the moment) and we are still facing the same problem.

I've spoken with the provider and they tell me the line is okay. I entered the following command (Please see attachment), is there anything from this output that points to the problem or is there something else I need to do.

Any other ideas?

New Member

Re: ADSL Virtual-Interface 2 Drops


I work in a DSL team, and This issue is ISP related. Or at least with the DSL line itself.

As you can notice, the Noise Margin during the outage gets too low:

Noise Margin: -2.5 dB 31.0 dB

While during normal operation it stays between 10 and 31 which is a perfect value:

Noise Margin: 11.0 dB 31.0 dB

Have your ISP check the line from your site, and also, a good workaround in the meantime would be replacing the Microfilter that your DSL line should be using... if you're not using one, i'd suggest you buying one and installing it on the DSL line.

Pls rate if helpful

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