Re: Unknown URL

[Reco <recoverym4n@gmail.com>]

	Hi.

On Wed, Feb 21, 2018 at 03:41:08PM -0500, Stephen P. Molnar wrote:
> I have just installed Stretch and have what, to me at least, is an unknown
> URL when I do apt update (as root).
> 
> [Connecting to prod.debian.map.fastly.net (2a04:4e42:b::204)]

That's because you have this in your sources.list:

> deb http://security.debian.org/debian-security/ stretch/updates main contrib

security.debian.org tries to redirect you to the mirrors that are
nearest to you.

It just so happens that your host has IPv6 address from somewhere, so
apt tries IPv6 first, then another, and finally falls back to IPv4.

For example, from here it looks like this:

$ wget -S --spider http://security.debian.org
Spider mode enabled. Check if remote file exists.
--2018-02-21 23:56:33--  http://security.debian.org/
Resolving security.debian.org (security.debian.org)...
2001:a78:5:1:216:35ff:fe7f:6ceb, 2a02:16a8:dc41:100::233,
217.196.149.233, ..
.
Connecting to security.debian.org
(security.debian.org)|2001:a78:5:1:216:35ff:fe7f:6ceb|:80
...

$ getent hosts 2001:a78:5:1:216:35ff:fe7f:6ceb
2001:a78:5:1:216:35ff:fe7f:6ceb lobos.debian.org

Therefore here security.debian.org = lobos.debian.org


Since prod.debian.map.fastly.net is reachable from here, I suggest you
to fix your IPv6 setup, or squash it altogether in case you don't
control it.

Reco