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Preventing isdn layer 3 going down on an BRI

we have BRI Port configured as network side:

interface BRI0/2/1

no ip address

isdn switch-type basic-net3

isdn protocol-emulate network

isdn point-to-point-setup

isdn layer1-emulate network

isdn incoming-voice voice

isdn skipsend-idverify


To this port an isdn phone is connected.

Outgoing calls from this isdn phone to the PSTN are no problem and working fine. But incoming calls to this port are only successfull some secondes ago after last external call from the connected isdn phone.

The problem is that some seconds after the last outgoing call from the isdn phone the isdn layer 3 is going down and the isdn status is going back to Tei-assigned.

Is there a command to prevent that isdn layer 3 is going down when it is inactive?

Hall of Fame Super Gold

Re: Preventing isdn layer 3 going down on an BRI

These are symptoms of layer1 going down, not just layer3.

You can collect "debug bri" and "debug isdn q921" to see what's going on, but there is no configuration you can apply to fix.

So you could just try upgrading IOS in the hope the issue goes away, it may or may not.