Most private landline phone users in Luxembourg use a FritzBox to connect their phones (often DECT phones) to the national telephone network, supposed they still have a landline phone in their home. Although that the FritzBox really does an excellent job at this and is very easy to use, I always felt that I wanted to have more control over my VoIP server. The path to go was for me to move over to locally hosted FreePBX server.

So I started installing FreePBX (16) in a virtual machine on my ProxMox server, providing it with decent resources (64 GB Disk, 4 GB RAM, 2 cores) and put it into the isolated Phone VLAN in my network, together with my VoIP phones (and my FritzBox phone server).

In order to get started with a single phone, you need to:

• define a SIP trunk (virtual phone line to the outside);
• create an extension for your phone in FreePBX;
• connect your VoIP phone to the FreePBX server, using the extension;
• define an outbound route for outgoing phone calls;
• define an inbound route for incoming phone calls;
• make sure FreePBX’s firewall let’s you connect your phones and your uplink phone line and does not interfere with the connections;
• make sure your local network’s firewall does not block communications between your FreePBX, the uplink server (Internet) and the internal phone devices.

Caution

I was experimenting with FreePBX using a second VoIP number and in the same time keeping my other number online through the Fritzbox. This allowed me to do outbound calls on the FreePBX attached phone using the second number, but I was unable to receive inbound calls on that line. When calling inbound from the cellphone, the line appeared ringing, but no phone (extension) received the call. No entries were found in the FreePBX log file neither. So I assume that running the Fritzbox and the FreePBX system in parallel in a home network seems to lead to routing issues. The Fritzbox seemed to be the master receiver, as the other VoIP number still worked fine. This is all hypothetical, but in my case, things didn’t work. Shutting down the Fritzbox, and waiting for a few minutes, allowed the FreePBX system to receive the incoming calls too.

Internal firewall

Go to the Connectivity menu, submenu Firewall. I guess you should run the Wizard to accomplish a basic configuration. Anyway, Make sure that the FreePBX main interface (eth0) is defined as Local(Local trusted traffic) under the Interfaces tab.

The networks tab should include all the devices that should be able to contact the FreePBX server:

• all your VoIP phones
• potential software phones
• your main computer (to manage the FreePBX system).
• Don’t forget to allow your external SIP server (uplink) to contact your FreePBX!

Network firewall

I needed to define a Port Forwarding rule in my router’s (Unifi Dream Machine Pro) firewall to allow the external SIP server (my uplink) to contact my internal FreePBX server. I specifically allow the external server’s IP to access the IP of my FreePBX on port 5060 on both (UDP, TCP) protocols.

It is also recommended to disable the Conntrack Modules in the router that handle SIP traffic (H.323 and SIP), although it might help if you are in a double-NAT network.

Go to the Connectivity menu, submenu Inbound Routes. Click the button: Add Inbound Route.

Add a route Description, a DID Number (important if you use several incoming phone numbers) and define Set Destination to an Extension or to a Ring Group (if you have defined one).

Go to the menu Connectivity, submenu Outbound Routes. Click on Add Outbound Route.

Define the Route Name and select the Trunk(s) to be used for outbound calls.

Define the Dial Patterns

Go to the Connectivity menu, Trunks submenu. Click Add trunk. Add a SIP (chan_pjsip) Trunk.

Define a Trunk Name and an Outbound CallerID.

Define the Dialed Number Manipulation Rules which defines what numbers can be called. Be careful which number structures you allow, as some numbers might become very expensive.

In the pjsip Settings under General, fill out the Username, the Auth username, the Secret and the SIP Server. These information should have been given to you by your VoIP provider. The SIP Server port is mostly 5060. Authentication should be set to Outbound. If your external SIP server has a fixed IP or hostname (and you are on a public dynamic IP), then Registration should be set to Send.

I also filled out the advanced tab information for Contact User, From Domain and From User. Not sure if this is absolutely necessary, but as iI was experimenting a lot to get things going, it is filled out in my case.

When you are done, hit Submit and Apply config.

We will configure FreePBX to send emails through a Gmail SMTP relay. FreePBX will use Postfix of the underlying Redhat Linux system to achieve this.

Create a Google app password

Login to your google account with the email address you want to use for sending the notifications from your FreePBX system. On the Google account management page, click on Security, then on 2-Step-Verification. At the end of that page, create an App Password for your FreePBX system.

Create a password file in CLI

Create or edit the sasl_passwd file:

sudo nano /etc/postfix/sasl_passwd 

Add the following line to it:

[smtp.gmail.com]:587 my_email_address@gmail.com:My Google App Password

You do not need to worry about the spaces in the app password. Then hash map the password file:

sudo postmap /etc/postfix/sysl_passwd

After this command ran, you will see a sasl_passwd.db file in /etc/postfix. Permission son this file should be root:root.

Configure Postfix to use the Gmail relay host

Add the following lines to the Postfix main.cf file:

sudo nano /etc/postfix/main.cf

myhostname = freepbx.my.domain
relayhost = [smtp.gmail.com]:587

#Enable SASL authentication
smtp_sasl_auth_enable = yes

#Disallow methods that allow anonymous authentication
smtp_sasl_security_options = noanonymous
smtp_sasl_tls_security_options = noanonymous
smtp_tls_security_level = encrypt

# Location of sasl_passwd
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd

Now restart your postfix service:

nano systemctl restart postfix

Test your Postfix installation

echo "This is a test email" | mail -s "Test mail" destination@email.address

Optional: force Postfix to rewrite your address

Sometimes messages are rejected if the from user and the sending user don’t match up. If this happens, you have to add the following lines to the generic configuration file:

sudo nano /etc/postfix/generix

root my.sending@email.address 
root@localhost my.sending@email.address 
root@localhost.localdomain my.sending@email.address 
root@freepbx my.sending@email.address 
root@freepbx.localdomain my.sending@email.address 
asterisk my.sending@email.address 
asterisk@localhost my.sending@email.address 
asterisk@localhost.localdomain my.sending@email.address 
asterisk@freepbx my.sending@email.address 
asterisk@freepbx.localdomain my.sending@email.address
vm@asterisk my.sending@email.address

Hash map the generic file:

postmap /etc/postfix/generic

You have to add the following line to thew main.cf file:

smtp_generic_maps = hash:/etc/postfix/generic

Don’t forget to restart the Postfix service.

Test your email from FreePBX

Go to the Admin menu, User Manager submenu, select the user you want to send an email to and hit the Send Email button.

Don’t forget to associate an email address to the user.