Pi-hole - hostname resolution not working except if I edit /etc/hosts

TangoEchoAlpha · 28 Jul 2019 at 15:23

So I am currently running Pi-Hole on a Raspberry Pi. Absolutely love it and when I get my home server up and running, might move it to a Debian container. Anyway, I digress - I am not able to get IP addresses to resolve to hostnames unless I actually edit the /etc/hosts file on my Pi. I am sure there must be a more elegant way of doing it!

So this image from my Pi-Hole web interface shows what I mean. I would like the local IP addresses to show their hostnames instead:

However localhost and vanguard resolve if I edit my Pi /etc/hosts file and then reboot:

According to the Pi-Hole web admin GUI, I should be able to achieve what I want by using conditional forwarding, which I have tried setting up as per the below image - 192.168.1.1 is by EdgeRouter:

But that doesn't work. Here are what I think are the relevant parts of my EdgeRouter setup. First is the DHCP setup - I'm using one DHCP server for eth1, called 'LAN1':

I've set the domain name to be LAN1 below, with DNS1 to be my Raspberry Pi's IP address:

And below you can see the static IP mappings for some of the devices:

And inside the DNS wizard on my EdgeRouter I've got the various hostnames setup, as I think the names under the DHCP server configuration are just a 'simple name' and not actually the network hostname...

I don't get why it doesn't work and have reached as far as I can go

Any ideas would be much appreciated and I've put it in the open source subforum as I'm hoping I'll get more help from here

TIA

Feek · 29 Jul 2019 at 07:41

The only way I've managed it is via the hosts file. I run pi-hole as a DHCP server as well and all my known clients have reserved addresses so when I add a new one, I just update the hosts file as well.

TangoEchoAlpha · 29 Jul 2019 at 10:58

Feek said:
The only way I've managed it is via the hosts file. I run pi-hole as a DHCP server as well and all my known clients have reserved addresses so when I add a new one, I just update the hosts file as well.

Cheers Feek, looks like I will just keep editing the hosts file

the-evaluator · 30 Jul 2019 at 08:53

Another way to do this is to add a new local zone into dnsmasq which Pi-Hole will then query.

Firstly you need to tell dnsmasq about this file you're going to create. Run the command:

Code:

echo "addn-hosts=/etc/pihole/lan.list" | sudo tee /etc/dnsmasq.d/02-lan.conf

That will create /etc/dnsmasq.d/02-lan.conf which contains the following:

Code:

addn-hosts=/etc/pihole/lan.list

Alternatively just use your text editor of choice and create the file.

Next you need to populate that file using the following format:

Code:

IPADDRESS  <tab>  FQDN  <tab>  HOSTNAME

Replace <tab> with tab, don't literally type <tab>

So if you take vanguard as an example, the file would look like this:

Code:

192.168.1.232  <tab>  vanguard.homedomain.com  <tab>  vanguard

Add in any other devices with a static IP and replace homedomain.com with whatever domain name you're using.

Then restart the DNS services with 'sudo pihole -g' (there's other ways, that's how I normally do it) and you should then be able to resolve vanguard in DNS. Check that with 'host vanguard' which would show the forward DNS resolution:

Code:

[root@pihole1 ~]# host vanguard
vanguard has address 192.168.1.232

Then to check the reverse DNS:

Code:

[root@pihole1 ~]# host 192.168.1.232
232.1.168.192.in-addr.arpa domain name pointer vanguard.homedomain.com.

You should then find that the charts in Pi-Hole start showing hostnames.

TangoEchoAlpha · 30 Jul 2019 at 12:50

Thanks for that @the-evaluator