Re: dhclient-${IFNAME}.conf stopped working after upgrade FC32 -> FC34

[Jason Vas Dias <jason vas dias gmail com>]

I did try :
   'set ipv4.dns 127.0.0.1
    save persistant
  '
in  'nmcli c e $uuid', but this did not work either after an up / down -
/etc/resolv.conf was not updated to contain only '127.0.0.1' - it did
ALSO contain '127.0.0.1', but as a suffix, not a prefix - this is not
what I want .
This did used to work with my old setup on FC32, but not on FC34 .
Is there any custom dhclient.conf file that is included in the current
implementation anymore ?
Thanks, Jason

On 31/05/2021, Jason Vas Dias <jason vas dias gmail com> wrote:
> Good day -
>
>   On an FC32 x86_64 box, which I just successfully upgraded to FC34 ,
>   now running NM 1.30.4-1.fc34.x86_64 :
>   I had some custom dhclient configuration files, which used to be honored
>   by NM - ie. they took effect before upgrade, but not after:
>
>     /etc/dhcp/{dhclient-ens1u2u4.conf,dhclient-wlp59s0.conf}
>
>   which contain:
>
> dhclient.ens1u2u4.conf :
>
> interface "ens1u2u4" {
>  send dhcp-client-identifier 34:48:ed:a8:7c:be;
>  send host-name "jvdspc.jvds.net";
>  supersede domain-name-servers 127.0.0.1;
> }
>
>
> dhclient.wlp59s0.conf :
> interface "wlp59s0" {
>  send dhcp-client-identifier 5c:80:b6:72:cb:7b;
>  send host-name "jvdspc.jvds.net";
>  supersede domain-name-servers 127.0.0.1;
> }
>
>
>   There are links to these files in /etc/dhclient-{ens1u2u4,wlp59s0}.conf ,
> and
>   /etc/dhclient.{ens1u2u4,wlp59s0}.conf .
>
>   These files used to be merged in to the effective DHCP client
>   configuration , on FC32, and all prior FC & RHEL releases I've used, in:
>   /var/lib/NetworkManager/dhclient-{ens1u2u4,wlp59s0}.conf
>   , in use for each interface, which is written for each 'up' transition,
>   but no longer.
>
>   I have in /etc/NetworkManager/NetworkManager.conf:
>
> [main]
> #plugins=ifcfg-rh
> dhcp=dhclient
>
>
>   I want to run my own ISC BIND caching nameserver,
>   which serves some authoritative zones and some RPZ (response policy) zones
> ,
>   and also tell any Dynamic DNS configured DHCP servers what I consider
>   my domain name to be.
>
>   I already had to disable systemd-resolved service after the upgrade, which
> also
>   broke using my own nameserver.
>
>   Please can anyone suggest how I can get this custom DHCP option content
>   included in the effective ISC dhclient (v4) options , without
>   hacking the source and building my own NetworkManager to write
>   its dhclient.conf differently,  which would be my logical next step ?
>
>   The command:
>
>   $ nmcli c m $UUID 'DHCP4.OPTION+=supersede
> domain-name-servers=(127.0.0.1)'
>
>   does not let me add a 'DHCP4.OPTION[32]', though DHCP4.OPTION[0 ... 31]
>   is listed in
>
>   $ nmcli c s $UUID
>
>   output - none of them are my custom dhclient-${ifname}.conf options
>   above.
>
>   It would be nice if there was some way to run a script to output
>   the superseded domain-name-servers list to a file like:
>   /etc/named-dns-forwarders.conf, which contains a named.conf
>   'forwarders {  $domain_name_server ; }; ' statement, for
>   my caching-only-nameserver, which has 'recursion' enabled,
>   which I could include in my /etc/named.conf, but since my
>   forwarders list does not change often, I can live with this.
>
>
> Thanks in Advance for any helpful replies, Best Regards,
> Jason