I have a Golang toy app that accepts connections on a TCP port, very similar to the example below.
No matter what I tried, I couldn’t get it to work until I ran fly ips allocate-v4 and from there it started working immediately.
It’s possible that I was doing something wrong on my end trying to connect to TCP via the IPv6 address with netcat <ipv6 addr> 5000, but it’s also possible that TCP connections over IPv6 might be collateral damage to this change?