PRI trunk between Asterisk servers does not work.

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Asterisk Users 4 Comments

In article <4FECCD0C.1020000@fivecats.org>,
James Sharp wrote:
> On 6/28/2012 3:53 PM, Ernie Dunbar wrote:
> > We have three Asterisk servers, Voip1, Voip2, and Voip3. Voip1 has a
> > Wildcard TE405P (3rd Gen), Voip2 has a Wildcard TE410P/TE405P (1st Gen),
> > and Voip3 has a Wildcard TE110P. Voip1 is the server that handles our
> > PRI to the PSTN and we hope will allow us to failover to other Asterisk
> > servers (ie, Voip2 and Voip3). Voip2 is our current production server,
> > and Voip3 is being turned into our next production server.
> >
> > We’re trying to build a PRI trunk between Voip1 and Voip3. Curiously
> > enough, we’ve already done this between Voip1 and Voip2, so one would
> > think that the same configuration would work between Voip1 and Voip3 as
> > well. However, it hasn’t gone so smoothly. If you’re wondering why we
> > don’t just use SIP trunking between these servers, it’s because faxes
> > are not reliable over SIP trunks. I am open to suggestions however.
> >
> > At any rate, the PRI trunk between Voip1 and Voip3 isn’t working, and
> > that’s my current problem.
> >
> > – I have built a T1 crossover cable, and it’s plugged in between Span 3
> > on Voip1, and Span 1 on Voip3.
> > – I have a green light on both PRI cards for the appropriate spans.
> > – Both servers detect their cards on boot.
> > – DAHDI is installed on both servers, and all diagnostics are good, ie.
> > dahdi_test returns good results, dahdi_tool shows that the alarms are
> > OK, and executing ‘dahdi show status’ on the Asterisk console shows the
> > same.
> >
> > The chan_dahdi.conf configuration for spans 3 and 4 on Voip1 looks like
> > this:
> >
> > ; Span 3: TE4/0/4 “T4XXP (PCI) Card 0 Span 4”
> > group=3
> > context=default
> > switchtype = national
> > signalling = pri_net
> > channel => 49-71
> > group = 63
> >
> > ; Span 4: TE4/0/4 “T4XXP (PCI) Card 0 Span 4”
> > group=4
> > context=default
> > switchtype = national
> > signalling = pri_net
> > channel => 73-95
> > context = default
> > group = 63
> >
> > Span 4 goes to Voip2, which has a working PRI trunk.
> >
> > The chan_dahdi configuration for Voip3 looks like this:
> >
> > group=1
> > signalling=pri_cpe
> > switchtype=national
> > context=local
> > channel=>1-23
> > dchannel=>24
> > ;channel=25-47,49-71,73-95
> > rxgain=0
> > txgain=0
> > busydetect=yes
> > busycount=5
> >
> > resetinterval=1800
> >
> > I have a test DID, the dialplan for which on Voip1 looks like this:
> >
> > exten => 604484XXXX,1,Dial(DAHDI/g3/604482YYYY)
> >
> > But when I call 604484XXXX from my cell phone, I get no output on the
> > Asterisk console on Voip3, and this output on Voip1:
> >
> >
> > — Executing [604484XXXX@local:1] Dial(“DAHDI/5-1”,
> > “DAHDI/g3/604482XXXX”) in new stack
> > [Jun 28 12:43:32] WARNING[4219]: app_dial.c:1286 dial_exec_full: Unable
> > to create channel of type ‘DAHDI’ (cause 34 – Circuit/channel congestion)
> > == Everyone is busy/congested at this time (1:0/1/0)
> > == Auto fallthrough, channel ‘DAHDI/5-1’ status is ‘CONGESTION’
> > — Accepting call from ‘778839ZZZZ’ to ‘604484XXXX’ on channel 0/5,
> > span 1
> >
> > I’ve also tried connecting span 3 to one of the other ports on Voip2
> > with the same configuration, and I get the same results. I’ve run
> > loopback tests on the TE110P and tested the cable thoroughly.
> >
> > Any input on this problem is greatly appreciated.
>
>
> You’ve got the spans configured as “group = 63” but you’re trying to
> dial out on group 3 (DAHDI/g3 rather than DAHDI/g63).

No, the group=63 lines are actually redundant. It is the settings *above*
each channel=> line that get applied to the channels when they are created.

To the OP: what does “pri show span 3” give you on Voip1?

It might be useful to see the complete chan_dahdi.conf from Voip1.
To save space, you can list it without comments like this:

# grep -v ‘^;’ /etc/asterisk/chan_dahdi.conf

Cheers
Tony

4 thoughts on - PRI trunk between Asterisk servers does not work.

  • Quoting Ioan Indreias :

    Okay, here’s /etc/dahdi/system.conf (it’s unmodified from the
    autogenerated file):

    # Autogenerated by /usr/sbin/dahdi_genconf on Mon Jul 26 22:53:04 2010

  • Quoting Tony Mountifield :

    It looks like this:

    # asterisk -rx ‘pri show span 3’
    Primary D-channel: 72
    Status: Provisioned, Down, Active
    Switchtype: National ISDN
    Type: Network
    Window Length: 0/7
    Sentrej: 0
    SolicitFbit: 0
    Retrans: 0
    Busy: 0
    Overlap Dial: 0
    Logical Channel Mapping: 0
    T200 Timer: 1000
    T203 Timer: 10000
    T305 Timer: 30000
    T308 Timer: 4000
    T309 Timer: -1
    T313 Timer: 4000
    N200 Counter: 3

    The only differences I see between ‘pri show span 3’ and ‘pri show
    span 4′ are that the status on span 4 is “Provisioned, Up, Active” and
    that the D-channel is different, which is to be expected.

    Okay, here you go:

    [channels]
    usecallerid=yes
    cidsignalling=bell
    cidstart=polarity

    facilityenable=yes
    hidecallerid=no
    callwaitingcallerid=yes
    callwaiting=no
    threewaycalling=yes
    transfer=yes
    echocancel=yes
    echocancelwhenbridged=no
    immediate=no

    group=1
    signalling=pri_cpe
    switchtype=national
    pridialplan=unknown
    relaxdtmf=yes
    context=local
    channel=>1-23
    rxgain=0
    txgain=0
    busydetect=yes
    busycount=5

    resetinterval=3600

    #include dahdi-channels.conf

    And dahdi-channels.conf looks like:

    group=3
    context=default
    switchtype = national
    signalling = pri_net
    channel => 49-71

    group=4
    context=default
    switchtype = national
    signalling = pri_net
    channel => 73-95

  • Quoting Tim Nelson :

    Excellent!

    Funny thing about that. Our original plan was to use a SIP trunk until
    we discovered that faxes don’t work worth a damn that way. Ergo, I
    didn’t compile libpri first.