Dual WAN single port

General Help
1

I am in the process of adding a SIP second trunk from my ISP and its on a private /30 IP, they are providing me a second port on the modem currently used. The issue is I only have the one ethernet port and the PBX needs access to the public and the private networks. My network switch I am using is a layer 3 so I can do configuration for ports and Vlans if needed.

My first questions is, I noticed that in FreePBX I can add a secondary or VLan off the main eth0. Is this what i need to do to allow both networks reachable to the PBX system?

2

Easiest way would be to add a second nic.

3

I wish I could but the system in use does not have any expansion capabilities.

4

Not even usb? Even though is not recommended to use a usb-to-ethernet adapter, you could try that way first.

If not, you can go the way of assigning two different IPs to the nic, it is not mandatory to use vlans.

5

This is easy to do with VLANs. I don’t know the details of your hardware or network, so I’ll pretend you’re using a simple ‘smart’ switch such as https://www.amazon.com/Ethernet-Unmanaged-Shielded-Replacement-TL-SG105E/dp/B00N0OHEMA/ or https://www.amazon.com/NETGEAR-Gigabit-Lifetime-Protection-GS105Ev2/dp/B00HGLVZLY/ .

On the PBX, set up a VLAN interface. If your NIC is eth0, use eth0.3 (for example). Configure it with a static IP address appropriate for your new trunk. Add the subnet to Local Networks (in Asterisk SIP Settings).

Connect port 1 of your switch to the PBX, port 2 to your normal LAN and port 3 to the modem port for the new trunk. Configure switch:
VLAN2: port 1 untagged, port 2 untagged.
VLAN3: port 1 tagged, port 3 untagged.
PVIDs: port 1 VLAN2, port 2 VLAN2, port 3 VLAN3.

Confirm that the PBX can ping hosts on your LAN and on the internet, as well as the new trunk interface.

Set up the trunk and test.

1 Like
6

Hello Stewart1, thank you for the info. I think i will give this a try but maybe I can get a little more information and help from you.

We currently have a Netgear GS728TP switch that is managed and I am able to do some configuration. My network is currently 10.10.99.0/24 and the private LAN is in the range of 172.17.3.120/29.

So from my understanding there are 2 VLAN’s configured, VLAN 2 is for normal internet and VLAN 3 is for the private LAN. All normal ports should be on VLAN 2 including ports for computers and printers. The PBX port should be VLAN 3.

As for the tagged and untagged this is where I get a little lost. I’m guessing this is the config;
port 1: untagged vlan 2, tagged vlan 3
port 2: untagged vlan 2
port 3: untagged vlan 3
port 4 to 24 : untagged vlan 2

7

This should be fine. Make sure that untagged packets coming into port 3 (from the new trunk) are sent to VLAN3. On some switches, this requires a separate ‘PVID’ setting.

8

Hello Stewart1,

This looks like it worked on a production setup. Thank you for the help.

9

This topic was automatically closed 7 days after the last reply. New replies are no longer allowed.