On Mon 09/May/2022 21:21:30 +0200 list-devuan wrote:
> tito via Dng wrote on 2022-05-09 04:54:
>>
>> Hi,
>> two usual culprits are network-manager and/or dhclient.
>> For network manager add in /etc/NetworkManager/NetworkManager.conf  [main]
>> section;
>>
>> dns=none
>>
>> for dhclient create a file  "/etc/dhcp/dhclient-enter-hooks.d/nodnsupdate"
>> with content:
>>
>> #!/bin/sh
>> make_resolv_conf(){
>>          :
>> }
>
> According to the man page dhclient-script(8), a file (of any name) in
> /etc/dhcp/dhclient-enter-hooks.d is invoked inline (so no shebang needed) if
> and only if it is executable.  I use a one line file containing:
>
>     make_resolv_conf(){ :; }
>
> Then chmod +x the file.


Some of that arcane is unveiled in Debian wiki:

     These packages include various configuration files for other
     packages (such as isc-dhcp-client). For example, resolvconf
     includes a file which modifies the make_resolv_conf shell
     function used by dhclient-script(8).
     https://wiki.debian.org/resolv.conf#Configuring_openresolv_or_resolvconf

Sorry for being late
Best
Ale
--