Adguard default port mapping

[superjke]

Describe the bug

When installing Adguard from the store the default port mappings seem to be incorrect. UDP + TCP 53 on the container is mapped to 531 on the host. This means with the default setup no DNS requests will reach Adguard - clearly it should be mapped to 53 on the host. Also after setip the web panel is hosted on port 80 on the container, this is also missing from the default port mapping.

To Reproduce

Steps to reproduce the behavior:

1. Go to App Store
2. Click on Adguard home
3. Click the dropdown > custom install
4. See default port mappings

Expected behavior

A clear and concise description of what you expected to happen.

Screenshots

[TheCorruptCat]

How can i fix this?

[TheCorruptCat]

I have the same issue

[dragonfire1119]

@superjke @TheCorruptCat Here is a tutorial that walks you through installing Adguard Home: https://youtu.be/7NGnCbxBf_U

[superjke]

How can i fix this?

This is what my port mapping ended up looking like in the settings.

port 53 includes the host ip because without it I was getting dns issues with other containers.

[fseesink]

To be clear, there are two issues here around the default port-mapping setup of the CasaOS Adguard Home app on the app store:

• The DNS mapping where port 53 (DNS) inside the container is mapped to port 531
• The Web UI mapping where port 3001 is mapped to port 3000

The first one I could almost understand, as many Linux distros may already have a resolver running. So by default not trying to bind to port 53 on the host avoids potential conflicts there. This then requires the admin of the system running CasaOS to first make sure that port 53 is actually available (i.e., that the host OS isn't already doing DNS), and then adjusting the settings to map the host's port 53 to the Adguard container's port 53. Unfortunately, by default, Adguard won't do anything if folks simply point their client devices at the IP of the CasaOS box, as they'll be trying to talk to port 53 for DNS while the mapping shows it's only listening on port 531 on the host.

The web UI mapping, however, is simply a mistake. By default, the settings should really be mapping

• host port 3001 to container port 80

This is because the first time a user of CasaOS runs Adguard after installing it, they go through a setup wizard where, by default, it has the web admin interface port set to port 80. If a new user simply answers the minimum number of items and leaves all the other presets alone, they'll have an install of Adguard that is listening on port 80 inside the container for web admin access.

I understand why 3000 shows up there, as it's often referenced in relation to setting up Adguard and what many Docker tutorials indicate using. But this should simply be set to 80 for the container, as that's the default listed when you configure Adguard in the setup wizard.

[ByteBolt556]

This is my config and I can access Admin UI from the port 3001 no problem. Now I just have problem with making it work properly haha

[dlm21]

This has been open for quite awhile. The problem I see is that it sets the host port to 531 which makes it useless for most clients needing dns resolution. My workaround is in a root shell for the casaos server itself:

systemctl disable --now systemd-resolved
echo 127.0.0.1 > /etc/resolv.conf

That should free up port 53 and let you set the Host ports from 531 to 53 for tcp and udp. Then queries from the casaos box itself should resolve locally and external queries should work as well.

[informant246]

@dlm21 I did the same thing - I disabled systemd-resolved on the server device and then updated the Host TCP and UDP ports from 531 to 53.

All my network traffic is now showing up in Adguard Home, but now I have a new problem - I cannot update CasaOS apps anymore! I get the following error when attempting to update any app:

Error response from daemon: Get "https://registry-1.docker.io/v2/": dial tcp: lookup registry-1.docker.io on 127.0.0.53:53: read udp 127.0.0.1:56327->127.0.0.53:53: i/o timeout

Does the resolv.conf file need to be updated at all? I did try the echo statement you provided but get a "permission denied" error.

EDIT, 2 WEEKS LATER: I was unable to figure out a way around this issue, so I basically just did everything in reverse:

1. Remove the server as my LAN DNS server in the router settings
2. Deactivated the Adguard Home container in CasaOS
3. Ran sudo systemctl enable systemd-resolved, sudo systemctl start systemd-resolved, sudo systemctl restart systemd-resolved to restore the systemd-resolved service
4. Restart the server
5. After logging back in, I was able to update apps as normal.

[NetoriKun]

@dlm21 I did the same thing - I disabled systemd-resolved on the server device and then updated the Host TCP and UDP ports from 531 to 53.

All my network traffic is now showing up in Adguard Home, but now I have a new problem - I cannot update CasaOS apps anymore! I get the following error when attempting to update any app:

Error response from daemon: Get "https://registry-1.docker.io/v2/": dial tcp: lookup registry-1.docker.io on 127.0.0.53:53: read udp 127.0.0.1:56327->127.0.0.53:53: i/o timeout

Does the resolv.conf file need to be updated at all? I did try the echo statement you provided but get a "permission denied" error.

EDIT, 2 WEEKS LATER: I was unable to figure out a way around this issue, so I basically just did everything in reverse:

1. Remove the server as my LAN DNS server in the router settings
2. Deactivated the Adguard Home container in CasaOS
3. Ran sudo systemctl enable systemd-resolved, sudo systemctl start systemd-resolved, sudo systemctl restart systemd-resolved to restore the systemd-resolved service
4. Restart the server
5. After logging back in, I was able to update apps as normal.

I had the same issue before but managed to solve it. The key is don't fully disable systemd-resolved — just prevent it from using port 53.
Here's how:

1. Edit systemd-resolved config:
   bashsudo nano /etc/systemd/resolved.conf
   Add or change this line:
   [Resolve]
   DNSStubListener=no
2. Restart systemd-resolved:
   bashsudo systemctl restart systemd-resolved
   Port 53 is now free for AdGuard Home to use without any conflict.
3. Update resolv.conf to point to AdGuard Home:
   bashsudo rm /etc/resolv.conf
   sudo bash -c 'echo "nameserver 192.168.1.X" > /etc/resolv.conf'
   Replace 192.168.1.X with your server's IP address.
   With this setup, Docker can still resolve DNS normally, CasaOS can update apps without errors, and all your LAN traffic still shows up in AdGuard Home. Hope this helps!