[Asterisk-Users] "Provisioned, Down, Active", but D-channel seems to be fine

[steve at daviesfam.org]

Hi,

I'm seeing rather odd behaviour on a new box with TE110P card.

I'm running the TE110P span with ccs,hdb3,crc4 in pri_net, connected to a 
second machine with a TE410P in pri_cpe.

The span is idle.

I'm using pri intense debug span 1 and can see the RRs going back and 
forth.

So - things are running along with the span showing "Provisioned, Up, 
Active" in pri show span 1.

Something happens and the span logs an alarm, and goes down.  All the 
channels go down.

Almost immediately, the alarm clears.  I see the RRs again.

But, pri show span 1 shows the span now as "Provisioned, Down, Active".

But all along we are exchanging RRs (receive ready) with the remote 
system.

So I'm pretty sure that the span is actually up again.  But why doesn't 
Asterisk agree...?

(Actually, I suspect that at the level of the D-channel it didn't really
go down, we just had a tiny layer-1 glitch).

Looking in the chan_zap code around line 8000, I see that when it gets an 
ALARM from zaptel is clears the DCHAN_UP flag.  But I don't understand the 
process by which the DCHAN_UP gets set to yes again.

Any comments or pointers?

Steve