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ISDN some pings timeout

Network with a 3640 with PRI at the central site. About xxx xxx dial in to the central side. One remote site got a problem after working for two years.

If I do a ping -t (same from both sides), some pings will timeout. For example the 12th and 13th, then 2 times ok, some timed out again, 10 times ok.

I have changed already the router on the remote site.

All other sites are working. Have also restarted the ISDN-NT.

  • Other Network Infrastructure Subjects

Re: ISDN some pings timeout

It's hard to say. I would suggest

the following (on both ends):

clear counters

start pinging (from either end)

sh interface - confirm that there are

no drops or errors after a ping failure

If you are using MPPP or any other

feature, try disabling it to see if that

makes a difference.

If the interfaces are clean, see if you

can determine if the packets are being

received and forwarded at either end.

You can try this with "debug ip packet

detail" on either end (careful, this will

be a lot of output), or with an analyzer

at either LAN end.