How to stop dhclient from updating resolvconf on Debian?

Question

I want to use certain DNS servers on my Debian, regardless of whatever I get through DHCP. I'm trying to configure dhclient to ignore those, but I can't seem to get it to work.

Per advice from this article I added supersede domain-name-servers 8.8.8.8, 8.8.4.4; stanza to my /etc/dhcp/dhclient.conf file. I also tried these answers from superuser.com and removed domain-name-servers and domain-search values from request directive. Both of those, applied separately as well as together, seem to have no effect. After running sudo dhclient -r and then sudo dhclient, I still find following entries in /etc/resolvconf/run/interfaces/enp2s0.dhclient:

domain lan
nameserver 192.168.1.1

which prompt resolvconf to put nameserver 192.168.1.1 in my /etc/resolv.conf file.

I double-checked if I don't miss any semicolons or similar syntax elements. How can I get my configuration to work? I don't want to remove resolvconf, since it manages changes in my nameservers when I use corporate VPN and it does it well. It looks like dhclient is the offending party here.

Here's my current /etc/dhcp/dhclient.conf with default comments removed for the sake of clarity:

option rfc3442-classless-static-routes code 121 = array of unsigned integer 8;

send host-name = gethostname();
request subnet-mask, broadcast-address, time-offset, routers,
        domain-name, host-name,
        dhcp6.name-servers, dhcp6.domain-search, dhcp6.fqdn, dhcp6.sntp-servers,
        netbios-name-servers, netbios-scope, interface-mtu,
        rfc3442-classless-static-routes, ntp-servers;

#supersede domain-name-servers 8.8.8.8, 8.8.4.4;

Update: per request in comment, here's output of ps ax | grep dhcp:

23528 pts/2    S+     0:00 grep dhcp

Solution 1

If you don't need resolvconf to manage your /etc/resolv.conf file, the simplest solution is to uninstall resolvconf entirely.

Solution 2

How to stop dhclient from updating resolvconf on Debian?

I don't want to remove resolvconf

You need to add domain-name-servers 8.8.8.8, 8.8.4.4 to

/etc/resolvconf/resolv.conf.d/base

And

/etc/network/interfaces

Regenerate resolv.conf then restart networking:

resolvconf -u
/etc/init.d/networking restart

Comments

[Red]

@RuiFRibeiro edited in.

[Rui F Ribeiro]

my fault...please change it to ps ax | grep dhc. Also do include cat /etc/network/interfaces, or at least the configuration of the relevant interface for this discussion.

[Rui F Ribeiro]

Have you commented out too the domain-name-servers from the require directive after the request line you show us?

[Alessio]

+1. apt-get purge --kill-kill-kill --burn-it-with-fire resolvconf.

[Red]

I'd like to avoid that, since resolvconf automatizes nameservers change when connecting to VPN and disconnecting from it. I should probably add that information to the question.

[user640916]

This is a brute force "solution" and makes it even harder to understand how the different component work together eventually. Here is a nice list of what accesses resolv.conf unix.stackexchange.com/a/527581/88177