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Service Provider said no problem....


I do not know where to start.. There is one WAN Link which having crypto VPN connectivity keeps on have WAN Link flipping,meaning up and down, up and down.

The Service provider has done a loopback test and said that there is no issue with the pyhsical layer..

How can I proceed ?any debug commands?


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Re: Service Provider said no problem....


You can take a look at your WAN interface to see if it has any connection transients, if so most likely your provider connection or your card is having problem.

There is a way to do a loopback test to your WAN interface to determine whether it is defective or not. I don't remember the link sorry.

On the other hand you need to know if the routing protocol you are using is facing recursive traffic issues. If so, it might be making the interface to go up and down.

Let me know if it helps.


Re: Service Provider said no problem....

Is it the line protocol that is flapping, or the interface is flapping as well? If it is just the line protocol, it could be an encapsulation thing, os something else on layer 2. If the interface is flapping as well, it most likely layer 1 i.e. physical.

Was the loopback done from both ends? You can ask the provider to loop their ends and you look at the result. Your interface should show looped. If it does not, or it is still flapping, the problem is most likely at your end, probably a bad interface.


Re: Service Provider said no problem....

What kind of errors are you getting when you do a sh int on your interface? If you are seeing a lot of input errors on your wan interface, then it is an issue with the provider. Hope this helps.

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