Re: install/57244: sysinst ignores manually-supplied DNS server address

[Tom Lane <tgl%sss.pgh.pa.us@localhost>]

The following reply was made to PR install/57244; it has been noted by GNATS.

From: Tom Lane <tgl%sss.pgh.pa.us@localhost>
To: gnats-bugs%netbsd.org@localhost, Martin Husemann <martin%duskware.de@localhost>
Cc: install-manager%netbsd.org@localhost, netbsd-bugs%netbsd.org@localhost
Subject: Re: install/57244: sysinst ignores manually-supplied DNS server address
Date: Sun, 26 Feb 2023 11:42:04 -0500

 Martin Husemann <martin%duskware.de@localhost> writes:
 >  Can you please provide the full /etc/resolv.conf that is created in your
 >  environment with the nameserver IP?
 
 What I saw when interrupting sysinst was
 
 # cat /etc/resolv.conf
 # Generated by dhcpcd from tlp0.dhcp, tlp0.dhcp6, tlp0.ra
 # /etc/resolv.conf.head can replace this line
 domain sss.pgh.pa.us
 nameserver 2600:4041:2eb:1c00::1
 # /etc/resolv/conf.tail can replace this line
 
 (manually transcribed from screen photo, there might be typos)
 
 What is in the hppa machine's normal /etc/resolv.conf is
 
 ;
 ; BIND data file
 ; Created by NetBSD sysinst on Sat May  7 18:29:16 2022
 ;
 search sss.pgh.pa.us
 nameserver 192.168.1.8
 nameserver 192.168.1.14
 
 I'm not sure to what extent I may have hand-edited that,
 though.  The file date is a few days later than May 7,
 so I changed it at least a bit.  Perhaps I added the
 second nameserver manually --- I don't recall ever
 trying to enter more than one nameserver in sysinst.
 
 I have a dhcpv4 server that is advertising 192.168.1.8
 and 192.168.1.14 as DNS servers.  Also, I have found
 no way to stop my Verizon router from advertising itself
 as a DNS server.  It does have DHCP turned off so I'm not
 quite sure what protocol it's using to do so, but some of
 my gear reports seeing 192.168.1.2 (the Verizon box's
 inside IP) as an autoconfigured DNS server, and the
 2600... IPv6 addresss shown above is the Verizon box's
 inside IPv6 address.
 
 Anyway, when I first ran "Configure network" and let it
 autoconfigure, it asked me for host name and domain anyway,
 and what I saw after the autoconfigure was the manually
 entered domain and host name, then the above 2600... IPv6
 address for nameserver, host IP 192.168.1.3 which is correct
 (but I think it must have gotten that from the kernel loader
 bootp protocol, as my DHCP server isn't set to allocate that),
 IPv4 gateway fe80::3ebd... which I think is one of my Verizon
 box's link-local addresses (this choice seems quite strange),
 and "IPv6 autoconf" being another 2600:4041:... address which
 it must have gotten by delegation from the Verizon box.
 
 In short it seems to have completely ignored the IPv4 DHCP
 server in favor of the IPv6 info.
 
 I then manually overrode the nameserver and IPv4 gateway addresses
 but left the "IPv6 autoconf" entry alone; perhaps that was
 a mistake?
 
 Anyway, ifconfig within the sysinst environment showed the
 192.168.1.3 address as assigned to tlp0, along with both
 the "autoconf" IPv6 address and another fe80::... address.
  
 >  There may be a timing issue with dhcpcd in the background overwriting the
 >  sysinst generated file.
 
 Looks like a good bet :-(.  Why is dhcpcd running at all,
 though?
 
 			regards, tom lane