CYcytzol·Jan 21, 2022
I set up a non-public-facing IPv6-only web server last night, so the issues are fresh in my mind! I'm fortunate enough to have an IPv6-capable home connection, and the hosting provider I use (Scaleway) charges extra for assigning IPv4 addresses to machines, so I thought I'd see how easy it would be to save a bit of money and make this machine IPv6-only. I've IP-filtered the host to only my home and my other servers, so having IPv4 support should be a waste.
The machine is now running fine, but I had a few roadblocks setting it up:
• My provisioning scripts download a release of 'dry'[0] from GitHub, which does not support IPv6. I ended up assigning my new machine a temporary IPv4 address and removing it later.
• The scripts also import a key from 'keyserver.ubuntu.com'[1], which, again, does not support IPv6. Attempting to connect just ti
Read the rest
med out, and if I hadn't just solved the other issue, I would have assumed the host was down.
• There seems to be a bug in Scaleway's cloud firewall (the things it calls Security Groups), where you cannot allow inbound ICMPv6, only standard ICMP (for IPv4). This meant my pings never responded and I thought the machine wasn't up when it was up.
Basically, what I want you to take away from this post is that if you disable IPv6, it's still the case that during maintenance, things are going to break, often mysteriously and with bad error messages, but outside of maintenance, things will likely run smoothly. My machine runs Sentry, and after the problems I had setting it up, I didn't dare run the Sentry './install.sh' script with IPv4 disabled as I didn't trust it to handle that case correctly — and even if the script reported no errors, I wouldn't have trusted there to actually be no errors. Since then, though, it's been running fine, so having an IPv6-only server is certainly possible, even if you have to give in and assign it an IPv4 address at the start, then take it away again later.
[0]: https://github.com/moncho/dry
[1]: https://keyserver.ubuntu.com/