[asterisk-users] BRI D-channel goes up and down

[Richard Mudgett]

> I have a B410P card with span ports set up as
> span=3,1,0,CCS,AMI
> span=4,2,0,CCS,AMI
> span=5,3,0,CCS,AMI
> 
> signalling = bri_cpe
> switchtype = euroisdn
> layer1_presence = ignore
> 
> However, I keep getting these messages over and over again:
> 
> [Dec 14 18:53:14] WARNING[22476]: sig_pri.c:1150 pri_find_dchan: Span
> 3: D-channel is down!
>   == Primary D-Channel on span 3 up
>   == Primary D-Channel on span 4 up
>   == Primary D-Channel on span 5 down
> [Dec 14 18:53:25] WARNING[22478]: sig_pri.c:1150 pri_find_dchan: Span
> 5: D-channel is down!
>   == Primary D-Channel on span 5 up
>   == Primary D-Channel on span 4 down
> [Dec 14 18:53:30] WARNING[22477]: sig_pri.c:1150 pri_find_dchan: Span
> 4: D-channel is down!
>   == Primary D-Channel on span 3 down
> [Dec 14 18:53:30] WARNING[22476]: sig_pri.c:1150 pri_find_dchan: Span
> 3: D-channel is down!
>   == Primary D-Channel on span 4 up
>   == Primary D-Channel on span 3 up
> 
> It seems I can dial out and in but I'm afraid I may be losing some
> calls if they happen to dial in/out right when a span goes down.
> 
> libpri-1.4.13
> dahdi-2.6.1
> asterisk-11.0.1

You will not lose any calls.  The BRI (layer 1), Q.921 (layer 2),
and Q.931 (layer 3) specifications were designed for this behavior.

The telco is bringing the protocol layers down to conserve power.
Astersk/libpri currently does not initiate bringing down the protocol
layers.  If the telco has an incoming call, it will bring the layers
back up before presenting you with the call.  For outgoing calls, the
layers are brought back up as well before the outgoing call is given
to the telco.

Richard