[Asterisk-Users] PRI problem???

[Bruce Komito]

My experience has been that the telco is the one that supplies the clock,
because they must keep all of their circuits and equipment in sync.  In
fact, they typically derive their clocking ultimately from a satellite
source.  At one time, we had a switch interconnected with trunks to the
ILEC, and we had to buy a similar clock to drive our equipment so that all
of our circuits were in sync with theirs, as well as the other telcos we
connected to.  Before we did this, our PRIs (which were used for data
only) would work for a while, but the modems dialed in to the PRI would
eventually drop off, as the clock slippage increased to the point of being
out of tolerance.  Eventually, the entire PRI had to be restarted.  When
we installed the clock, all of the problems disappeared.

Bruce Komito
High Sierra Networks, Inc.
www.servers-r-us.com
(775) 284-5800 ext 115


On Mon, 24 May 2004, Timothy R. McKee wrote:

> I thought the timing priority setting was for which incoming timing signal
> was used as the primary clock source, so I set the PRI as the highest
> priority clock source.  In the telco world this is that way it normally
> works.  Does the priority setting mean something different in zaptel.conf?
>
> My apologies to the group re the B channel restarts issue.  My searches must
> have been too specific.
>
>
>
> ====================================================================
> Timothy R. McKee
>
>
> -----Original Message-----
> From: Bruce Komito [mailto:brucek at bagel.com]
> Sent: Monday, May 24, 2004 08:30
> To: Timothy R. McKee
> Cc: asterisk-users at lists.digium.com
> Subject: Re: [Asterisk-Users] PRI problem???
>
> Tim, I would double check the timing.  It seems odd that you would supply
> clock rather than the switch, and if you get clock slips, that could
> certainly account for what you are seeing.  Feel free to contact me off-list
> if you need more info or have any questions.
>
> Bruce Komito
> High Sierra Networks, Inc.
> www.servers-r-us.com
> (775) 284-5800 ext 115
>
>
> On Sun, 23 May 2004, Timothy R. McKee wrote:
>
> > I have just finished installing a new asterisk box at my work.  The
> > box is quite hefty, dual Zeon 2.8s with SCSI drives and 2Gb of memory.
> > I have a 4 port Digium T1 card for channel bank and PRI access.
> >
> > I activated a PRI from a local CLEC (DMS-500 based, National protocol).
> > This PRI is on slot 2 of the card and is set as the primary timing source.
> > It is ESF/B8ZS.
> >
> > All the software is latest CVS HEAD as of 5/22/04.
> >
> > My problem lies in random intermittent drops of calls.  The entire PRI
> > seems to disappear, dropping all current established calls.  I see
> > occasional printouts on an asterisk management console showing all 23
> > B channels resetting with no reason given:
> >
> > pbx1*CLI>
> >     -- B-channel 1 successfully restarted on span 2
> >     -- B-channel 2 successfully restarted on span 2
> >     -- B-channel 3 successfully restarted on span 2
> >     -- B-channel 4 successfully restarted on span 2
> >     -- B-channel 5 successfully restarted on span 2
> >     -- B-channel 6 successfully restarted on span 2
> >     -- B-channel 7 successfully restarted on span 2
> >     -- B-channel 8 successfully restarted on span 2
> >     -- B-channel 9 successfully restarted on span 2
> >     -- B-channel 10 successfully restarted on span 2
> >     -- B-channel 11 successfully restarted on span 2
> >     -- B-channel 12 successfully restarted on span 2
> >     -- B-channel 13 successfully restarted on span 2
> >     -- B-channel 14 successfully restarted on span 2
> >     -- B-channel 15 successfully restarted on span 2
> >     -- B-channel 16 successfully restarted on span 2
> >     -- B-channel 17 successfully restarted on span 2
> >     -- B-channel 18 successfully restarted on span 2
> >     -- B-channel 19 successfully restarted on span 2
> >     -- B-channel 20 successfully restarted on span 2
> >     -- B-channel 21 successfully restarted on span 2
> >     -- B-channel 22 successfully restarted on span 2
> >     -- B-channel 23 successfully restarted on span 2 pbx1*CLI>
> >
> > (This is from an asterisk console started with -rvvvv.)
> >
> > Has anyone encountered similar behavior in the past?  If so, what was
> > the resolution?
> >
> > Thanks,
> >
> > Tim McKee
> >
> > configs:
> >
> > zaptel.conf
> > #
> > # span 1 is for channel bank (24 FXS)
> > span=1,2,2,esf,b8zs
> > # span 2 is for NuVox PRI (1-23B, 24D) span=2,1,2,esf,b8zs # span 3 is
> > unused span=3,0,0,esf,b8zs # span 4 is unused span=4,0,0,esf,b8zs # #
> >
> >
> > zapata.conf
> >
> > [channels]
> > ;
> > ; Default language
> > ;
> > language=en
> > ;
> > ; Default context
> > ;
> > context=dialnational
> > ;
> > signalling=fxo_ks
> > use_callerid=yes
> > callwaiting=no
> > restrictcid=no
> > usecallingpres=yes
> > callwaitingcallerid=no
> > threewaycalling=yes
> > transfer=yes
> > cancallforward=yes
> > callreturn=yes
> > echocancel=yes
> > echocancelwhenbridged=no
> > echotraining=yes
> > relaxdtmf=no
> > rxgain=0.0
> > txgain=0.0
> > callgroup=1
> > pickupgroup=1
> > immediate=no
> > amaflags=billing
> >
> > <channels 1-24 omitted>
> >
> > ;
> > ; NuVox PRI
> > context=sdnpri
> > ;
> > switchtype = national
> > pridialplan = unknown
> > signalling = pri_cpe
> > callerid=asreceived
> > group = 2
> > channel => 25-47
> >
> >
> >
>