Comment by phire
18 days ago
> In theory you could turn off IPv4 NAT as well but in practice most ISPs will only give you a single address
So, I randomly discovered the other day that my ISP has given me a full /28.
But I have no idea how to actually configure my router to forward those extra IP addresses inside my network. In practice, modern routers just aren't expecting to handle this, there is no easy "turn of NAT" button.
It's possible (at least on my EdgeRouterX), but I have to configure all the routing manually, and there doesn't seem to be much documentation.
You should be able to disable the firewall from the GUI or CLI for Ubiquiti routers. If you don't want to deal with configuring static IPs for each individual device, you can keep DHCP enabled in the router but set the /28 as your lease pool.
> So, I randomly discovered the other day that my ISP has given me a full /28.
Where is this? Here new ISP customers don't even get a single IPv4 unless you beg for it.
Not even CGNAT?
In the US many large companies (not just ISPs) still have fairly large historic IPv4 allocations. Thus most residential ISPs will hand you a single publicly routable IPv4 regardless of if you're using IPv6 or not.
We'll probably still be writing paper checks, using magnetic stripe credit cards, and routing IPv4 well past 2050 if things go how they usually do.
Out of curiosity how did you discover this?
Went to double check what my static IP address was, and noticed the router was displaying it as 198.51.100.48/28 (not my real IP).
I don't think the router used to show subnets like that, but it recently got a major firmware update... Or maybe I just never noticed, I've had that static IP allocation for over 5 years. My ISP gave it to me for free after I complained about their CGNAT being broken for like the 3th time.
Guess they decided it was cheaper to just gave me a free static IPv4 address rather than actually looking at the Wireshark logs I had proving their CGNAT was doing weird things again.
Not sure if they gave me a full /28 by mistake, or as some kind of apology. Guess they have plenty of IPs now thanks to CGNAT.
More like even if they looked at the logs they aren't about to replace an expensive box on the critical path when it's working well enough for 99% of their customers.
I once had my ISP respond to a technical problem on their end by sending out a tech. The service rep wasn't capable of diagnosing and refused to escalate to a network person. The tech that came out blamed the on premise equipment (without bothering to diagnose) and started blindly swapping it out. Only after that didn't fix the issue did he finally look into the network side of things. The entire thing was fairly absurd but I guess it must work out for them on average.