How Are Channels Numbers Assigned

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Asterisk Users 1 Comment

Hi All

I have this system here where:

# dahdi_hardware pci:0000:07:04.0 wctdm24xxp+ d161:8005 Wildcard TDM410P
pci:0000:07:09.0 wcte11xp+ e159:0001 Digium Wildcard TE110P T1/E1 Board

channels are
0-31 for TE110P
32-35 for TDM410P

I want to insert a new TE110P. How will these new channels be assigned?
What is the dahdi_genconf logic for these assignments?

Is there a way to force these assignments to prevent they to change if I
insert/remove any card from the system?

chan_dahdi.conf is a bit confusing to me. What makes the configuration for one channel be finished and start the configuration for the next channel?

Would you point me any docs on this matter?

Asterisk is 11.7.0
Dahdi is 2.7.0
Ubuntu 14.04.5 LTS



One thought on - How Are Channels Numbers Assigned

  • (1-31)

    Your version of dahdi is 2.7.0, which is a bit of a shame. Slightly newer versions introduced span assignment: you can specify in
    /etc/dahdi/assigned_spans.conf to which span number and channel number will be used by each device. dahdi_genconf can generate a default one for you, but see also ‘dahdi_span_assignment dump’. Which means you would not depend on a specific modue loading order.

    That aside, dahdi_genconf just uses whatever dahdi gives it. With automatic span assignments, the order of spans (and channels) is set by the order in which the kernel modules happened to load.

    The best I have so far is the README of dahdi-tools. A copy of it is in