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New Member

wan down

My customer is having an ABR on their premise. This ABR is only one among the 20 ABRs within the country. Number of internal routers are connected to this ABRs thru frame relay.

Whats happening is that, this particular ABR, along with the whole internal routers connected, intermittently goes down in 1 min and then goes up. The frequency of this scenario is minimum once a day. What could be the problem?

Could it be a DOS attack? How to check that?

The Autonomous System Admin was telling the customer that its a virus on the routers. Its my first time to hear that. But is there any?

Could anyone suggest steps to tackle this problem.

Thanks a lot.

  • Other Network Infrastructure Subjects

Re: wan down

I haven't heard of a virus for routers either. Forget it, maybe he/she may have meaned a "bug" in software. What do you exactly mean saying "going down"? Router restart (can be seen with "sh ver")? But I don't think so. What do you see on logging? ("sh logging buffer") To see this check if you've configured "logging buffered debugging" in router cnfig.

Goood Luck.

New Member

Re: wan down

wan communications will be down in a minute then comes up without doing anything after that...

New Member

Re: wan down


first of all, iwould check if the layer 1 or 2 is down (sh int xy).

if "only" the layer2 is down, then i would do a "debug frame lmi" to see if you have all lmi frames from the fr-switch.

if also layer 1 is down then you should check if there are any errors, crc.

perhaps you have trouble withe telecom line to you next fr-switch!

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