[Asterisk-Users] Resolving timing issues with dual PRIs in a TE411P

[Casey Boone]

you could try setting the * box to pull timing from each pri connected 
to it and set the nortel to be a master for that circuit and see if that 
helps any

Casey

Anthony Rodgers wrote:
> Greetings, everyone, and Happy New Year!
> 
> I have a question relating to running two PRIs into a single TE411P. We 
> have been experiencing echo, noisy MOH, poor audio call quality and so 
> forth that started at around the time we introduced the second PRI into 
> the equation. Here is our zaptel.conf:
> 
> span=1,2,0,esf,b8zs
> bchan=1-23
> dchan=24
> #clear=1-24
> loadzone = us
> defaultzone=us
> 
> span=2,1,0,esf,b8zs
> bchan=25-27
> dchan=48
> #clear=1-24
> loadzone = us
> defaultzone=us
> 
> And here is our zapata.conf:
> 
> [trunkgroups]
> 
> [channels]
> 
> context=incoming
> usecallingpres=yes
> echocancel=128
> callerid=asreceived
> usecallerid=yes
> echocancelwhenbridged=yes
> echotraining=500
> 
> ; Nortel PBX
> rxgain=2.0
> txgain=-17.0
> group=1
> callgroup=1
> pickupgroup=1
> switchtype=national
> signalling=pri_net
> facilityenable=yes
> channel => 1-23
> 
> ; Allstream PRI
> rxgain=-2.0
> txgain=-17.0
> group=2
> callgroup=2
> pickupgroup=2
> switchtype=dms100
> signalling=pri_cpe
> facilityenable=no
> channel => 25-27
> 
> musiconhold=default
> 
> We are master to the Nortel PBX, which gets its clocking from Telus (a 
> telco), and slave to the Allstream (another telco), from where the 
> Asterisk gets its clocking.
> 
> We have been through the IRQ/APIC/hyperthreading thing already, and our 
> gain levels were set using ztmonitor. zttest gives Best: 100.000000 -- 
> Worst: 99.987793 -- Average: 99.998923 after 885 passes. We have 
> another, identical server that plays MOH with no problems without a PRI 
> attached (presumably using internal clocking), and that same server and 
> another similar server had no issues for months with only one PRI 
> attached (one had the Nortel and one had the Allstream, with an IAX 
> trunk between them).
> 
> Is it possible that the two PRIs have timing differences between them 
> that could cause problems? If so, how best could we resolve them?
> 
> Regards,