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New Member

ISDN BRI dial problems

We have two cisco2621 routers with BRI interfaces acting as backup for a serial link. Whenever we try and make a call we get the message "no free B channels" despite the fact that the channels are not in use. we have had the line tested by the telco and they have found no problems. We are using switch type basic-net3 as we are in the uk. As well as this I cannot get the Layer 2 status to stay at Multiple Frame Established. After about thirty seconds it goes to TEI_ASSIGNED state. Any help would be appreciated

Cisco Employee

Re: ISDN BRI dial problems

In Europe, The bri line will negotiate the TEI when the router makes the call. So after first call the layer 2 should stay at "Multiple_frame_established"

Now looking from the debug Q921 you have posted, Router got the DISCp from switch which force him to go for layer 2 down.

Try "isdn tei-negotiation first-call" under the bri interface..Thx..Tejal

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