resolv.conf keeps old configurations

[pamiller3]

I have been searching for this answer for awhile and came up with nothing. I recently upgraded from ubuntu 10.04 to 12.04 and I understand the auto config of the resolv.conf file and I have edited the /network/interface to include the changes but it keeps old configurations from when it was 10.04.

EXAMPLE:
network/interface=

auto eth0
iface eth0 inet static
address <IP_ADDRESS>
netmask 255.255.255.0
gateway <IP_ADDRESS>
network <IP_ADDRESS>
broadcast <IP_ADDRESS>

dns-search <NEW_DOMAIN>
dns-domain <NEW_DOMAIN>
dns-nameservers <NEW_IP_ADDRESS> 4.2.2.1 8.8.8.8

I look into the /resolv.conf and it shows this:

nameserver <NEW_IP_ADDRESS>
nameserver 4.2.2.1
nameserver 8.8.8.8
search <NEW_DOMAIN>
domain <OLD_DOMAIN>
search <OLD_DOMAIN>
nameserver <OLD_IP_ADDRESS>
nameserver 4.2.2.1
nameserver 4.2.2.2

Any suggestions would be great

[Karlchen]

Hello, pamiller3.

Automatically updating resolv.conf will work on Ubuntu 12.04 only in case resolv.conf itself is located in the folder /run/resolvconf. The folder /etc has got to hold a symbolic link to /run/resolvconf/resolv.conf.

karl@ubuntu12 /etc $ ls -l resolv.conf
lrwxrwxrwx 1 root root 27 Aug  5 13:43 resolv.conf -> /run/resolvconf/resolv.conf
karl@ubuntu12 /etc $

Kind regards,
Karl

[pamiller3]

Alright I made the changes and removed the old configurations out of the /run/resolvconf/resolv.conf and then did an interface restart and it still shows the old configurations

[steeldriver]

Hi I *think* that when you do a dist-upgrade from a release that pre-dates the resolvconf service, your old manual DNS config gets saved to one of the files in /etc/resolvconf/resolv.conf.d/ (either /etc/resolvconf/resolv.conf.d/original or /base - not sure) and then appended to the dynamically generated /etc/resolv.conf file - maybe look in there and see if you can find the old entries?

See here:- http://www.stgraber.org/2012/02/24/dns-in-ubuntu-12-04/

[pamiller3]

That seems to have worked, I eliminated the contents of the /etc/resolvconf/resolv.conf.d/original file and it worked. Thanks for that.

A follow up is I am trying to add the line dns-domain in the network/interface file and when I do that it does not add that to the resolv.conf file. Is there anyway that I can make sure that this server is added to the domain?

[steeldriver]

sorry I'm not familiar with a dns-domain field - I've only seen dns-nameservers and dns-search

[pamiller3]

Alright I maybe barking up the wrong tree, I found that command on a blog...or forum..or somewhere around the inet.

Is there an easy command to confirm the hostname is part of the domain. For example: hostname.domain.com

Thanks so much for the help

[steeldriver]

not sure exactly what you are looking for - in a general context you can get the host's fqdn using

hostname -f

but that's not exactly related to your /etc/network/interfaces DNS settings

[jdthood]

That seems to have worked, I eliminated the contents of the /etc/resolvconf/resolv.conf.d/original file and it worked. Thanks for that.

A follow up is I am trying to add the line dns-domain in the network/interface file and when I do that it does not add that to the resolv.conf file. Is there anyway that I can make sure that this server is added to the domain?

The more correct thing to do would have been to eliminate the symlink /etc/resolvconf/resolv.conf.d/tail -> original and replace it by /etc/resolvconf/resolv.conf.d/tail -> /dev/null. But emptying /etc/resolvconf/resolv.conf.d/original works just as well.

[jdthood]

A follow up is I am trying to add the line dns-domain in the network/interface file and when I do that it does not add that to the resolv.conf file. Is there anyway that I can make sure that this server is added to the domain?

Resolvconf only ever adds a "search" line to resolv.conf, never a "domain" line. This is because "search" lines do everything "domain" lines do, but are more versatile. The glibc resolvconf only uses either "domain" or "search", not both. So "search" it is.

In /etc/network/interfaces the use of "dns-domain" options works (and is treated as synonymous with "dns-search") but is deprecated in favor of "dns-search" for the reason just given.