Re: install/57864: Install first tries to load from cdn.netbsd.org using ipv6

[Sergei K <sk757a%outlook.com@localhost>]

The following reply was made to PR install/57864; it has been noted by GNATS.

From: Sergei K <sk757a%outlook.com@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: install/57864: Install first tries to load from cdn.netbsd.org
 using ipv6
Date: Thu, 18 Jan 2024 21:24:49 +0500

 On 18.01.2024 10:55, Martin Husemann wrote:
 > The following reply was made to PR install/57864; it has been noted by GNATS.
 >
 > From: Martin Husemann <martin%duskware.de@localhost>
 > To: gnats-bugs%netbsd.org@localhost
 > Cc:
 > Subject: Re: install/57864: Install first tries to load from cdn.netbsd.org
 >   using ipv6
 > Date: Thu, 18 Jan 2024 06:53:58 +0100
 >
 >   On Thu, Jan 18, 2024 at 03:45:01AM +0000, sk757a%outlook.com@localhost wrote:
 >   > Install gives priority to ipv6 addresses and this leads to long waits
 >   > and messages Can't connect to [2a04:4e42:...]:80 Operation timed out.
 >   > Sometimes many times in a row. My provider does not support ipv6, but
 >   > ipv6 works on the local network.
 >   
 >   The installation assumes a working internet connection (if you use the
 >   network download parts). It does not prefer IPv6 over IPv4 or vice
 >   versa, but assumes you can use the addresses returned from DNS if
 >   there is a route.
 >   
 >   You have several options:
 >   
 >    - fix the DHCP setup to not provide a default route for IPv6
 >    - fix the DNS setup (e.g. by using a DNS cache that filters external
 >      IPv6 responses)
 >    - pick a sane provider that properly supports dual stack access
 >      (yes, I know that my be hard)
 >    - use a tunnel service to get proper external IPv6 routed to your
 >      local network (Hurricane electric are an example of a free offer for that)
 >   
 >   So even if that may sound a bit harsh, I would not consider this a bug
 >   in the installer.
 >   
 >   Martin
 
 Thank you for the clarification, Martin and Robert. Yes, the problem is 
 definitely not with install, but rather with the behavior of the system 
 with defaults. Even after I waited for all these ip6 requests to fail 
 with timeout and successfully installed the system, pkg_add also worked 
 with huge delays (~7m) ip4 used only after lan-only ip6. I found two 
 ways to fix this:
 
 1. Add -4 to dhcpcd_flags
 2. ip6addrctl=YES
 
 I understand that my network setup is far from ideal and I can just 
 disable ip6 completely without any consequences, but I would like to 
 point out that all other operating systems that I use do not experience 
 similar difficulties.