Multiple Gateways on one subnet

Hello Experts,

I have a customer that has two buildings connected with Wi-Fi and one subnet 192.168.0.x.  Building A has the WAN circuit and Building B has to go over the Wi-Fi to get internet. They want to put a new WAN circuit into Building B and add another FortiGate to go out to the internet but still maintain the Wi-Fi LAN. Can I do this without having to re-subtnet  Building B? Can I deploy multiple Gateways without creating any problems?
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Sure, if you put the fortigate in the same 192.168.0 LAN , you just have to change the main gateway of building B equipments only. Then you will add the old WiFi persistent route with a lower priority (metric). Lower metric get higher prio :)

route add MASK metric 10

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penntechsAuthor Commented:
The persistent WiFi connection is a site to site connection with the sole purpose of extending the LAN backbone. I don't think I can break that connection easily.
You do not need to break it.
Just add the new fortigate and the corresponding IP as default gateway for your equipments in Buiulding B.
Or do i miss something ?
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Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
If you configure your devices with static IP instead of DHCP, then yes, changing the default gateway on all devices in B is all you have to do. Nothing else.

If you use DHCP - ouch. You can trick the routing table to override the DHCP default gateway somehow by setting more specific routes, that is:
  route -p add mask 192.168.0.x
  route -p add mask 192.168.0.x

That way the default gateway remains in building A, but Internet traffic is routed to 192.168.0.x.
penntechsAuthor Commented:
Ok I will try it
penntechsAuthor Commented:
That worked thanks
Qlemo"Batchelor", Developer and EE Topic AdvisorCommented:
The "creative" part lies more in http:#a40402468 then in http:#a40402301, so I would have expected to get more points :(
penntechsAuthor Commented:
Sorry Olemo...I didn't change the routing table
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