asterisk users - Mar 2005 - timing/clock problem

Hi all,


We have been fighting with telco for a entire week.
Today they came here with a LITE3000 to analyze what is going on.


When I configure zaptel with no external clock, E1 gets aligned/synchronized 
with bit rate in 2048000 bps, both me and telco.
span=4,0,0,ccs,hdb3,crc4

But when I configure span4 to get clock source from telco they become 
unsynchronized. TElco bit rate stays in 2048000 bps, but asterisk stays on 
2048443 pbs!!
span=4,1,0,ccs,hdb3,crc4

Telco1 (Intelig) send alarms and I do not sync to then.

I have another PRI circuit used for data connections from Telco2 and I used it 
for testing.
Telco2 (Telemar) do not send alarms and I sync to then.


Does anybody have some idea about what is happening?

Regards
[]s
-- 
Alex G Robertson
NOC - Microlink

You checked the crc4 setting, right? And the protocols...

On Wed, Mar 02, 2005 at 06:49:53PM -0300, Alex G Robertson
wrote:
> But when I configure span4 to get clock source from telco they become 
> unsynchronized. TElco bit rate stays in 2048000 bps, but asterisk stays on 
> 2048443 pbs!!
> span=4,1,0,ccs,hdb3,crc4
Hope this helps,
-- 
Martijn van Oosterhout
Ecomtel Pty Ltd

On March 2, 2005 04:49 pm, Alex G Robertson wrote:
> When I configure zaptel with no external clock, E1 gets
> aligned/synchronized with bit rate in 2048000 bps, both me and telco.
> span=4,0,0,ccs,hdb3,crc4
What are the other spans connected to, and what are their span= lines?
> I have another PRI circuit used for data connections from Telco2 and I used
> it for testing.
> Telco2 (Telemar) do not send alarms and I sync to then.
Asterisk cards can only sync to one source per CARD.  So if you have a TE410P 
in there and you're trying to sync to two telcos, it won't work.  Now 
granted, the telcos should all be pretty damn solid for timing and using one 
over the other shouldn't cause frame slips but this is the nature of the 
Digium multiport T1/E1 cards.  You would need to use two cards (at double the 
interrupt rate) or try to convince one telco to sync to you.  I'd be 
surprised if you'll get the latter one to occur.  :-)

-A.

Yes, I did. It is correct.

We have tried with and without crc4.

Martijn van Oosterhout wrote:
> You checked the crc4 setting, right? And the protocols...
> 
> On Wed, Mar 02, 2005 at 06:49:53PM -0300, Alex G Robertson wrote:
> 
>>But when I configure span4 to get clock source from telco they become 
>>unsynchronized. TElco bit rate stays in 2048000 bps, but asterisk stays
on
>>2048443 pbs!!
>>span=4,1,0,ccs,hdb3,crc4
> 
> 
> Hope this helps,
-- 
Alex G Robertson
NOC - Microlink

Hi everybody,

After some advice from you, we changed the order of my spans in the card.

It was in slot 5 in this order.
T1 (channelbank)
T1 (channelbank)
E1 (empty, with a loopback for testing porposes)
E1 (Telco - PRI/ISDN)

Now it is this way
E1 (Telco - PRI/ISDN)
E1 (empty, with a loopback for testing porposes)
T1 (channelbank)
T1 (channelbank)

But when I chaged the order, I got too many lost interrupts. So I begin to chage
  slots and it gets OK in slot 2. I can sync to telco's clock as we hope!


So, if you are having some problem - I think any kind of problem like 
interruptions, clock slips, HDLC (Abort and Bad FCS) - try EVERY configuration 
set as possible. I mean fisicaly configurations. try slot 1, 2, 3... every thing
you can.

Ok. It sounds like a Mandrake solution :-), but it can solve your problem.


Thanks to everybody how helped me.
-- 
Alex G Robertson
NOC - Microlink