@ipguy said in Why can't I use a /8 ?:
the next remote network, 10.3.0.0/28
the next remote network, 10.4.0.0/28
I am with @JKnott here - this doesn't make a lot of sense..
So you have a remote device.. And it has a /28 or even multiple /28s on the other end of it.. Ok what does that have to do with your tunnel network?
How many devices are going to connect to the openvpn server? 8000? So your tunnel network would only need to support 8000 IPs.. So a /19 would allow for 8190 address - so if using subnet vs net 30, each modem would only being getting 1 IP for the tunnel.. So 8190 modems. What networks are on the other end of the tunnel has nothing to do with the tunnel network.. The tunnel network allows for how many clients can connect to that server.. Using a /16 tunnel would allow for 65k devices to connect.. Even using net30 addressing you would still have way more than enough for 8000 connections.
Also with
the next remote network, 10.3.0.0/28
the next remote network, 10.4.0.0/28
Your wasting a lot of space between those networks as mentioned.. Your using a whole /16 just to assign a /28... Think we are missing some info here.
But you could route multiple network across your 1 IP used to connect for the tunnel..
I think a better understanding of what your doing or wanting to do exactly.. How are these modems connecting to you now?