But I don't have ipv6...

I figured its time I should really start learning ipv6 after listening to the Packet Pushers podcast on the subject - https://packetpushers.net/podcast/ipv6-buzz-017-the-ipv6-year-in-review/

ipv6 will at some point be required knowledge, so I figured I would learn it now since I know literally nothing about it, other than the addresses look funny. I originally had it completely disabled, but I noticed that everything over ipv6 was snappier.

I actually have native IPv6 at home with Comcast, but my colocated server doesn't have it, so testing between two points would be hard.

I decided to setup an HE.net ipv6 tunnel

This is a free service from Hurricane Electric that gives you a routed /48 allocation, for free. You can apply here - https://tunnelbroker.net/

After getting it all setup, I now have complete ipv6 connectivity

It was quite easy to setup in pfSense. If you want to get it set up and happen to run a pfSense firewall, the pfSense guide is quite good - https://www.netgate.com/docs/pfsense/book/network/ipv6-tunnel-broker.html

I didn't have to mark the gateway as default, as that option no longer exists. Also the DHCPv6 part seemed to just take effect automatically, you can follow my screenshots if it didn't though. I used the /48 allocation

It does lack screenshots though, so here are some you can use to follow on with. This is not a complete guide, but just something you can reference

First, make sure ipv6 isn't blocked

And then make sure ipv6 and ipv4 icmp is allowed. You need to allow ipv4 for the tunnel to function, and ipv6 relies heavily on icmpv6

Don't want to allow icmp? read this: http://shouldiblockicmp.com/

Make sure your LAN rule allows ipv6 too

Now make the GIF interface (Not related to the images, I guess)

Assign the interface, and rename it to something better and enable it

Make sure the gateway is setup

And select the default ipv6 gateway

Make sure you have some ipv6 DNS servers (I made sure I have ones that support DNS over TLS)

Then make sure the DHCPv6 server and RA is setup

That should be everything!