NAT Troubles or how my ISP screwed me over

Couple of days ago, I woke with my inbox filled with alerts from my monitoring service, the dashboard was lit up like a Christmas tree. I'm not new to having downtimes, but this was the most unusual one: the servers were alright, the internet connection was fine, but the services were inaccessible. I had a bad feeling about this one.

You see, most of my internet presence comes out of my bedroom. This website, my search engine, and even my favourite instant messaging platform is operated right out of my bedroom. This has been possible because I've had a publicly accessible IP address. It's dynamically allocated but thanks to DDNS, it works! Everything was fine until my ISP decided to put me behind a NAT. I told them that I'm okay with paying for a static IP, but they said they only offer static IPs for enterprise accounts. I love my ISP, I think they are great but a static IP costs ₹200/month(~$3) only, but they want me to upgrade to a plan that costs four times more than what I'm paying now.

I can't buy an enterprise connection and I can't migrate the fleet to the could because it's expensive, and my parents will disown me. The only logical option is to switch to an ISP that offers static IPs. But in the meantime I have set up a tunnel between my servers and a cheap DigitalOcean box using frp.

It's only been a few hours since the tunnel was set up but so far, everything seems to be okay. There's a client and a server component, the client is run on machines behind NAT and the server on a machine that's exposed to the internet. The client connects to the server and sets up a reverse tunnel. They support a wide range of protocols including HTTP, HTTPS, UDP and TCP. Compared to my previous setup, performance is a little sluggish, but that's expected since the application now sits behind two reverse proxies instead of one. But it's usable.

Here's an example frpc(frp client) configuration for HTTP and HTTPS:

[libreddit-https]
type = https
local_ip = 127.0.0.1
local_port = 443
use_encryption = true
use_compression = true
host_header_rewrite = libreddit.batsense.net
custom_domains = libreddit.batsense.net

[libreddit]
type = http
local_ip = 127.0.0.1
local_port = 80
use_encryption = true
use_compression = true
host_header_rewrite = libreddit.batsense.net
custom_domains = libreddit.batsense.net

Hopefully IPv6 deployment increases and this post is rendered useless but if there's someone out there who's trying to get past the NAT and requires assistance, feel free to contact me!