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New Member

Configure 2 lines for 2FXO card

Guys, this might sound silly to you. I'm a novice at VOIP and need help setting up my system. Someone configured it the first time and is not accessible anymore. They setup the system to use one PSTN line on a 2FXO card, so only one person could dial out at a time. We now have 4 lines, but getting 2 to work is proving difficult enough. I tried simply plugging the lines in at the same time, but when a person places a call it uses both lines at the same time. So on one you get an engaged tone while the other connects, and you can hear the two on your phone at the same time.

I've attached the config of the router for all to see. I'm not sure whether additional lines are provisioned via Call Manager or the router.

I'll be installing an additional FXO card on the router for 2 more lines, but first I have to get the current card to use two, so that 2 people can call out at the same time, and when one person calls it uses only one line.

Your help in pointing me in the right direction would be most appreciated.


Re: Configure 2 lines for 2FXO card

to get the second fxo to dial out do the following:

R(config)# dial-peer voice 2 pots

R(config-dial-peer)# preference 2

R(config-dial-peer)# destination-pattern .T

R(config-dial-peer)# port 1/0/1

this will allow the outbound calling of the second fxo.

New Member

Re: Configure 2 lines for 2FXO card

Thanks gpulos,

I tried your config changes. Unfortunately they didn't solve my problem.

My problem is not that I can't use the 2nd port, but that when I dial out it's using both port at the same time. So on the handset I can hear a busy tone as well as the person talking on the other end because one line connects while the second fails for obvious reasons.

If I call a mobile it connects and begins to ring while I also hear a message requesting me to leave a voicemail all at the same time.

Your help is appreciated

New Member

Re: Configure 2 lines for 2FXO card

Almost sounds like you're using a cable that splits into multiple RJ21 connectors for connecting into the FXO ports. is this the case?

If so, I'd recheck the termination & pinout or better yet, use two different RJ21 cables, one for each FXO connection.

New Member

Re: Configure 2 lines for 2FXO card

Each port has it's own cable, which plugs into a seperate wall socket that has it's own telephone number.

Is there anything I need to add into call manager to activate the second port?

New Member

Re: Configure 2 lines for 2FXO card


I had a very similar problem. Check that the cables used to connect the FXO ports only have two wires terminated on the RJ11 conector (pins 2&3) and not all 4.Having all 4 conected can case this type of problem.

regards colin

New Member

Re: Configure 2 lines for 2FXO card

Thanks Colin,

That seems to have helped a bit. Now I can make a call with the other cable plugged into the 2nd port and not have the 2nd line make a call at the same time.

My new problem is that I can't get 2 people to make a call at the same time, as soon as the 2nd caller presses the last digit they get a busy signal. This is not affecting the first caller.

Many thanks,


New Member

Re: Configure 2 lines for 2FXO card

Hi Mike

I noticed a few posts ago someone suggested a change to your router config. However it looks to me that you have a callmanager server controlling your gateway with mgcp which means you dont need the config they suggested. So if its there remove the config they suggested. You will need to look on your callmanager under "device"and "gateway" and make sure the new port is configured the same as the old one and it then work.



Re: Configure 2 lines for 2FXO card

Once you verify that it is configured, you also need to make sure it is included in the Route Group config, under Route Plan, route/hunt, route group - analog ports are included individually.

Mary Beth

New Member

Re: Configure 2 lines for 2FXO card

Thank you all for your help. My outgoing calls are now working well. I can have multiple outgoing calls at the same time.

However my incoming calls are no longer working. I have attendant numbers configured on both ports going to different extensions in the office. When someone dials in all they are now getting is a dialling tone after one ring. That one ring is not heard on the handset in my network. Previously my incoming calls were working.

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