So my IT predecessor(s) setup the IP space here on a external routable subnet not owned by this company (192.1.1.0/24). A redo is in order, but I am mentally roadblocked on the route to take going forward.
Right now we are using about 60% of our /24 IP space. There has been growth but that is likely to slow down some in the DHCP client space. I will be undertaking a new virtualization project that will consume some IPs but in theory I could probably squeeze everything into a /24, but there will come a time where I would at least need to go to a /23.
But, in theroy, why stop there? Why not go down to a /16 or /8. Yes it would be a massive waste of IP space, but each segment could be managed in the future. VoIP on a simplified VLAN that could be a segmented /24 subnet from my /16 or /8, etc.
It seems like overkill. Even if I went with a subnet-per-device type the most efficient would be a /22 (Switches/Appliances, Severs, VoIP, DHCP Devices).
Right now I don't have really good Layer 3 managed capabilities. We have one managed switch, and two more coming in (simple core switches), but I never really liked Layer 3 management at the switch side, I'd rather at a traditional router or a FW/router device. Problem is we have a simple SonicWall TZ100 which will not handle Layer 3.