setting up two UTM instances to overcome license.

From a legal standpoint, you can't do that.  Only one live instance with a single license.  There's two things you can do to reduce the license IP count:

1)  Any devices that don't need internet access, network printers being a good example, remove the default gateway address from their settings.

2)  Run devices through another router behind the UTM NATed.  For example if you use a wireless router.  The wireless routers WAN address will be within the scope of the subnet on the UTM internal interface, while the wireless devices will be NATed on a different subnet.  The only IP address the UTM will count is the external address of the wireless router.

RE: #2, if you setup another router (route #2) behind UTM (route #1), how do you enable devices to communicate with one another? For example. My Sophos UTM (Router #1) settings are shown below.  What should be the Subnet and Gateway values in Router #2 to ensure devices to connect to one another without adding to the Sophos UTM IP count?

Router 1

LAN IP 192.168.0.1

Subnet 255.255.255.0

Gateway 192.168.0.1

DHCP Range 192.168.0.10-40

Say the subnet behind your wireless router is 192.168.2.0/24 and the wireless router has 192.168.0.254 in your UTM's internal network, you will want a Static Gateway route in the UTM like '192.168.2.0/24 -> 192.168.0.254'.

Is that what you were looking for?

Cheers - Bob

BAlfson said:

Say the subnet behind your wireless router is 192.168.2.0/24 and the wireless router has 192.168.0.254 in your UTM's internal network, you will want a Static Gateway route in the UTM like '192.168.1.0/24 -> 192.168.0.254'.

Is that what you were looking for?

Cheers - Bob

Thanks Bob for your guidance.  Just double-checking. Would the static gateway route be:

192.168.1.0/24 -> 192.168.0.254 OR 192.168.0.1/24 -> 192.168.0.254?

BAlfson said:

Say the subnet behind your wireless router is 192.168.2.0/24 and the wireless router has 192.168.0.254 in your UTM's internal network, you will want a Static Gateway route in the UTM like '192.168.1.0/24 -> 192.168.0.254'.

Is that what you were looking for?

Cheers - Bob

Thanks Bob for your guidance.  Just double-checking. Would the static gateway route be:

192.168.1.0/24 -> 192.168.0.254 OR 192.168.0.1/24 -> 192.168.0.254?

Can't quite get this to work.  The details:

Sophos UTM 192.168.0.1 (/24)

NM 255.255.255.0

GW 192.168.0.1

DHCP 192.168.0.10-40

 

Wireless router

LAN IP 192.168.0.90

Subnet behind router 192.168.2.0/24

NM 255.255.255.0

GW 192.168.0.1

 

Under Sophos UTM > Interfaces & Routing > Interfaces > Static Routing

I've created a New Static Route as Gateway Route.

Network: Internal (Network) (aka 192.168.0/24)

Gateway: 192.168.0.90 (the LAN IP of Wireless Router)

Sorry, I had a typo that I corrected above.  You want 192.168.2.0/24 -> 192.168.0.254 and no other.

Cheers - Bob