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isdn connections


here's my pb.

I have a 801 isdn directly connected onto a


apparently, I can't make any outside calls.

the q921 debug tells me this :


Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:

00:28:29: ISDN BR0: Outgoing call id = 0x800F, dsl 0

00:28:29: ISDN BR0: Event: Call to 00559674399 at 64 Kb/s

00:28:29: ISDN BR0: process_bri_call(): call id 0x800F, called_number 0055967439

9, speed 64, call type DATA

00:28:124560864860: CC_CHAN_GetIdleChanbri: dsl 0

00:28:124554092544: Found idle channel B1

00:28:29: ISDN BR0: Activating

00:28:29: ISDN BR0: L1 is IF_ACTIVE

00:28:29: ISDN BR0: Incoming call id = 0x000A, dsl 0

00:28:29: %ISDN-6-LAYER2UP: Layer 2 for Interface BR0, TEI 64 changed to up.

00:28:124554092544: ISDN BR0: LIF_EVENT: ces/callid 1/0x800F HOST_DISCONNECT_ACK

00:28:124554051584: ISDN BR0: Error: Unfound B-channel on Disconnect_Ack - calli

d 0x800F

00:28:124554092544: ISDN BR0: HOST_DISC_ACK Voice cid 0x800F error....

Success rate is 0 percent (0/5)


00:28:39: %ISDN-6-LAYER2DOWN: Layer 2 for Interface BR0, TEI 64 changed to down

00:28:171798691839: L3: NLCB watch! cid 0x4BCC9C cr 0x0 ev 0x211 ces 1 dsl 0

the weird thing is that I can make calls with a Eicon card for example which makes me thing think something'wrong with the router's config.

The config has been tested on a direct isdn line

and it works.

can somebody help me, thanks.

VIP Purple

Re: isdn connections


there could be various reasons for this, since I have not seen the config of your router, here are some possible reasons:

Check with your ISDN provider that the service is set to accept calls via analogue services as well as digital - it is an option on the ISDN switch.

Are you running PPP multilink by any chance ? if so, make sure that the ppp multilink command is configured under the BRI as well as under the Dialer interface.

Try and change you dialer idle-timeout to 0 or soemthing high like 65000 (0 means to never disconnect), just to check if your router is actually requesting the disconnect.



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