2 3G modems

RouterOS General
1

Hi everyone
Just a quick question. I was wondering if any has tried hooking up 2 3G modems to a rb433uah router board.
I wanted to do this so I could share the bandwidth of both modems to a wireless AP.
Much thanks for any ideas or comments in advance.
Rhyan

2

Do you have 3G modems/routers with ethernet ports?

If you do, set them up as follow for equal cost routing (not the best way to use multiple WAN links, but a good place to start):

3G router #1:
Ethernet IP: 192.168.254.1, 255.255.255.0
Enable NAT
Plug into ether1 of Routerboard

3G router #2:
Ethernet IP: 192.168.255.1, 255.255.255.0
Enable NAT
Plug into ether2 of Routerboard

ROUTERBOARD:
IP on ether1: 192.168.254.2/24

/ip address add address=192.168.254.2/24 interface=ether1

IP on ether2: 192.168.255.2/24

/ip address add address=192.168.255.2/24 interface=ether2

Use both 3G routers as DNS

/ip dns set servers=192.168.254.1,192.168.255.1 allow-remote-requests=yes

Set up equal cost (load balancing) default gateway

/ip route add dst-address=0.0.0.0/0 gateway=192.168.254.1,192.168.255.1 check-gateway=ping

Set up simple NAT/masquerade rule

/ip firewall nat add chain=srcnat action=masquerade

Then configure the LAN/WLAN IP, DCHP and other.

3

Will this work with USB 3G modems as well?

4

Not sure. We normally connect ethernet 3G routers (with USB dongle) onto the ethernet ports of a Routerboard.