Server 23.10 DNS restrictions

[lisanels47]

I have ubuntu server 23.10 running great, it provides dhcp and dns to the network.

lisa@server:~$ host microsoft.com
microsoft.com has address 127.0.0.1
microsoft.com mail is handled by 10 microsoft-com.mail.protection.outlook.com.
lisa@server:~$

As above on the server I put microsoft.com in the hosts file, and you can see the response.

But on the clients respond like this:

lisa@lisa-Legion-Y545-PG0:~$ host microsoft.com
microsoft.com has address 20.76.201.171
microsoft.com has address 20.112.250.133
microsoft.com has address 20.231.239.246
microsoft.com has address 20.236.44.162
microsoft.com has address 20.70.246.20
microsoft.com has IPv6 address 2603:1030:c02:8::14
microsoft.com has IPv6 address 2603:1030:b:3::152
microsoft.com has IPv6 address 2603:1010:3:3::5b
microsoft.com has IPv6 address 2603:1020:201:10::10f
microsoft.com has IPv6 address 2603:1030:20e:3::23c
microsoft.com mail is handled by 10 microsoft-com.mail.protection.outlook.com.
lisa@lisa-Legion-Y545-PG0:~$

lisa@lisa-Legion-Y545-PG0:~$ cat /etc/resolv.conf
# This is /run/systemd/resolve/resolv.conf managed by man:systemd-resolved(8).
# Do not edit.
#
# This file might be symlinked as /etc/resolv.conf. If you're looking at
# /etc/resolv.conf and seeing this text, you have followed the symlink.
#
# This is a dynamic resolv.conf file for connecting local clients directly to
# all known uplink DNS servers. This file lists all configured search domains.
#
# Third party programs should typically not access this file directly, but only
# through the symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a
# different way, replace this symlink by a static file or a different symlink.
#
# See man:systemd-resolved.service(8) for details about the supported modes of
# operation for /etc/resolv.conf.


nameserver 192.168.10.6
search mynet.net
lisa@lisa-Legion-Y545-PG0:~$

The 10.6 address is my server, and I'd like to find a way to make it's named respond to clients like it does on the server itself.

[currentshaft]

How does the server provide DNS? What program are you using to do so? Does it have a configuration option to honor /etc/hosts?

[Impavidus]

Not directly relevant to your issue, but just a heads-up: Ubuntu 23.10 will reach end of life in just 17 days. Try and upgrade to 24.04 within two weeks. You may prefer to deal with your current issue after that, as a release upgrade may affect it.

It's typically best to run servers on LTS releases. 24.04 is an LTS release, with standard support until April 2029.

[lisanels47]

The server is running bind9/named. So it uses it's hosts file and then gets DNS via the assigned 'forward' .
For some reason, the ubuntu clients bypass this and do their own DNS lookups outside of my server.

[currentshaft]

From one of the clients:

dig a microsoft.com @192.168.10.6

I use dnsmasq, not bind9, but I wouldn't expect /etc/hosts to be honored by either program. You probably want to just NXDOMAIN the entire microsoft.com zone in your configuration instead.