OpenVPN uses the same trick to establish a higher-priority default gateway: def1 -- Use this flag to override the default gateway by using 0.0.0.0/1 and 12

OpenVPN uses the same trick to establish a higher-priority default gateway: def1 -- Use this flag to override the default gateway by using 0.0.0.0/1 and 128.0.0.0/1 rather than 0.0.0.0/0. This has the benefit of overriding but not wiping out the original default gateway. This works because routing tables prioritize "tighter" routes. I do think that 128.0.0.0/1 would only map to 1/2 of the address space. I cannot find the isc-dhcp server config files in the source code to verify. :disappointed: