The struggle to get Caddy installed in an IPv6-only machine

[Jitdor (Kenny Yu)]

Not exactly asking for help here, but I wanted to highlight a current issue for deploying Caddy in an IPv6-only environment.

Because both the domains apt.fury.io and github.com are not IPv6-ready (none of these names serves AAAA records), it is not possible to simply clone the source code to build the binary or to add the repository to apt package manager in an IPv6-only environment.

This can be overcome via a dirty fix that involves messing with the hosts file and some iptables mangling or socat actions with the help of a forwarding node that has dual IPv4/IPv6 network stack. It would be nice to see a more long-term fix, though.

[francislavoie]

Interesting! I’ll reach out to Gemfury and see if they could add IPv6 support. I don’t think I’d be able to make a dent in the issue re Github though.

[francislavoie]

Wow, Gemfury were real quick to fix this one

Hello Francis,

Thanks for the suggestion. I’ve just added an AAAA record for “apt.fury.io”.

Looks like it works now:

$ curl --verbose -6 https://apt.fury.io/caddy/Packages
* Trying ::ffff:54.243.76.156...
* TCP_NODELAY set
* Connected to apt.fury.io (::ffff:54.243.76.156) port 443 (#0)
....

Thanks again,

Gemfury

[Jitdor (Kenny Yu)]

Thank you! That was fast!!

[skyfaller (Nelson Pavlosky)]

You could try mirroring Github to somewhere else that has IPv6 support. ping6 sourcehut.org seems to indicate that SourceHut is resolvable over IPv6, unlike github.com. And I’ve heard really good things about SourceHut’s build system, if that’s something you might be interested in tinkering with.

For what it’s worth, I would like to encourage IPv6 support wherever possible, even though I’m not attempting to live IPv6-only.

[francislavoie]

There’s a discussion here about GitHub supporting IPv6

Cannot reach any github.io page via IPv6

[Jitdor (Kenny Yu)]

Apparently there’s another broken link from AWS, so apt install still doesn’t work :

The following NEW packages will be installed:
  caddy
0 upgraded, 1 newly installed, 0 to remove and 13 not upgraded.
Need to get 12.0 MB of archives.
After this operation, 34.1 MB of additional disk space will be used.
Err:1 https://apt.fury.io/caddy  caddy 2.0.0
  Could not resolve 's3.amazonaws.com'
E: Failed to fetch https://s3.amazonaws.com:443/gemfury/gems/5AyyLujQRXi5atoAaiKp3QyfjOfRZ7/caddy_2_0_0_linux_amd64_deb?x-acct=CKg6y&Signature=J1dp8l9ENjaDQgw07raH6Qfjjp4=&Expires=1589163565&AWSAccessKeyId=AKIAJSF6GIIIIQAC3D6Q  Could not resolve 's3.amazonaws.com'

[matt (Matt Holt)]

Until the Internet is unbroken, do you think you can just download a .deb and use that directly?

[francislavoie]

Looks like Amazon does support IPv6 but only on “dualstack” URLs:

Using Amazon S3 dual-stack endpoints - Amazon Simple Storage Service

I sent a note to Gemfury, not sure if they’ll be able to fix anything though.

[Jitdor (Kenny Yu)]

Sure do. Meanwhile I can help to host a copy of the .deb and .rpm binaries as a stop-gap measure. Thanks.

[francislavoie]

Got another reply from Gemfury:

Hello again,

We found that the implementation of this was also quite straightforward, so we’ve expedited and shipped it. Your account will now download from the dual-stack S3 endpoint:

$ curl -L --verbose -6 -I https://apt.fury.io/caddy/files/ver_1RZIEj/caddy_2.0.0_linux_armv6.deb
* Trying ::ffff:50.17.199.37...
* TCP_NODELAY set
* Connected to apt.fury.io (::ffff:50.17.199.37) port 443 (#0)
...
* Issue another request to this URL: 'https://s3.dualstack.us-east-1.amazonaws.com:443/...'
* Trying ::ffff:52.217.39.54...
* TCP_NODELAY set
* Connected to s3.dualstack.us-east-1.amazonaws.com (::ffff:52.217.39.54) port 443 (#1)
...

Thanks again for the feedback,
Gemfury

Mind giving it a shot @Jitdor?