Help with inbound/outbound differentiation

I have an OpenVox A800E44 card (analog PSTN, 4FXS/4FXO). At the moment I only have two FXO analog lines connected. The system is up and running with inbound and outbound routing with no issues. However, I would like to be able to use both lines as outbound but only one line as inbound. Can somebody please help me with the entire configuration?

Mmmm, you have two analog lines… they will always be used for incomming calls.

The only thing you can do is not answer the one incomming line, but the line is still busy while the number that is linked to that line is being called…

Why not switch to a voip provider? Then you can do all the tricks you want.

There has to be away…

What if

  1. I put context = from-zaptel in zapata.conf instead of context = from-pstn
  2. Add Zap Channel, the channel I want to allow inbound indicated from asterisk cli “zap show channels” and give it a DID
  3. Allow the DID given above to the Inbound Route

Does the above make any sense?

The above indicates that you are using a version of Asterisk that hasn’t been supported for many years (zapata.conf).

I don’t think Asterisk supports Direct In Dialling on analogue lines.

“Inbound Route” sounds like something in FreePBX. DID may also be FreePBX terminology, here. Peer support for current versions of FreePBX can be had at https:///

FXO modules expect to receive ringing current. FXS one expect to send it. You cannot software configure one to do the job of the the other.

Indeed I am using a very old version of Asterisk, version 1.4.x.

Bottom line, I am willing to do the upgrade to something new but will it do what I am asking?

Here is the scenario:

  1. Two PSTN lines (say Line1 and Line2) both connected to FXO ports on the OpenVox A800P card
  2. Want only Line1 to be answered by the system (ignore Line2 when ringing)
  3. Want to be able to use both Line1 and Line2 for calling outside

Is this possible at all? Upgrading to a new version of an Asterisk implementation is possible.


You might be able to do it by putting the second line into a context where extension s never calls Answer. I haven’t used dahdi analogue lines, so I can’t be sure.

Outbound calls can be handled simply by putting them in the same group.

Note that ringing is busy, and there is no way of rejecting calls on analogue lines, so a caller on the second line will be able to block it for a long time and it might be be better to answer and drop the call, rather than ignoring the ringing.

You are correct.

Sidebar for other readers: using Digium-brand and Sangoma-brand cards supports Asterisk. Using an OpenVox card doesn’t; it puts money into the pockets of people who don’t contribute to Asterisk.