Dual WAN for VoIP

RouterOS Beginner Basics
1

Hello,

We are a VoIP provider and we’re evaluating the MikroTik RouterBoard router at a customers request, and need some help on something I’m sure is pretty simple to do. The unit we are testing in the lab is the RouterBOARD 951-2n, and it’s running 5.26 code level.

The standard deployment would be two WAN connections for a small office environment - say WAN1 is a cable modem and WAN2 is a DSL modem. In both cases, the WAN connection would be DHCP (that is the customer in this case isn’t using a static IP address).

The LAN side would also be doing DHCP (say 192.168.88.0/24) - and for this deployment, not using VLAN’s.

Could someone please share with us a simple setup that would allow the dual WAN deployment as described above… we are not looking for load balancing… simply for the router to automatically switch from WAN1 to WAN2 upon failure (failure could be the modem fails, the ISP is no longer routing traffic, etc.)

Assistance would be greatly appreciated to allow us to determine if we recommend MikroTik as a solution to our customers.

Thank you!

Mark

2

Hi Mark,

First suggestion would be to upgrade into ROS 6.x (6.12 is latest).

I use a 951-2n at home with great success, for the price they can do a fair bit.

What you are describing is certainly possible, however I’m currently not able to type it out for you. Essentially you will need to:

  1. Set up DHCP Client on the 2 ports that will be WAN1 and WAN2
  2. On WAN2 when adding the DHCP Client, set Default ROute Distance to higher number (maybe 10)
  3. Create DHCP Server on your LAN port with ip ranges etc, making sure the gateway IP you are giving out is statically set to the ethernet port
  4. Create 2x ‘masquerade’ rule in firewall/nat, one with out-interface as WAN1, the other with out-interface as WAN2.

Thats as basic as I can explain it for now, if no one else chimes in with some help I will try and go into a bit more detail later on when I have more spare time.