Mac OS Sonoma use Port 53

Looks like some system demon of macOS use this port

That’s not my experience. Consider this:

% sw_vers
ProductName:		macOS
ProductVersion:		14.0
BuildVersion:		23A339
% sudo nc -u -l 53

I can then message it using:

% nc -u 127.0.0.1 53

Can you reproduce this with nc? If so, what does lsof report?

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—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

alex@alex ~ % sw_vers
ProductName:		macOS
ProductVersion:		14.0
BuildVersion:		23A344

For UDP looks like it can send and receive messages. But if I try TCP mode:

alex@alex ~ % sudo nc -l 53   
nc: Address already in use

lsof report for port 53:

COMMAND   PID           USER   FD   TYPE             DEVICE SIZE/OFF NODE NAME
mDNSRespo 209 _mdnsresponder   54u  IPv6 0x374deabe82ef1a55      0t0  UDP *:domain
mDNSRespo 209 _mdnsresponder   55u  IPv4 0x374deacce7bb82ad      0t0  TCP *:domain (LISTEN)
mDNSRespo 209 _mdnsresponder   56u  IPv6 0x374deabe73abbd95      0t0  TCP *:domain (LISTEN)

Interesting. That’s not what I’m seeing on my macOS 14 machine:

% sudo lsof | grep '*.domain'
% 

And nc works as well:

% nc -l 53
^C

Something has caused mDNSResponder to listen on port 53 and I’m not sure what. Do you have Internet Sharing enabled?

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Internet sharing disabled. I took a few extra tests. So looks like if I switch off docker - port 53 is free. So the problem is related to Docker. I shure that other containers not using this port. I found information about a simular issue here: https://github.com/docker/for-mac/issues/5335

People propose to turn off Virtualization Framework feature - but for me it didn't help. Tommorow will try other solutions. If you have ideas what can help pls share them here.

I have the same problem on macos 13.6 on Intel macbook pro. Is it possible to make port 53 available on macos?

I tried it with my MacBook 15 2018. First I updated docker for the last version. Tried on Mac os Ventura - everything is ok. After that, I updated Mac OS to Sonoma and immediately got this problem. And the worst problem is that now I can't roll back Mac OS to Ventura. It just shows me an error((( I spent 5 hours yesterday. Now both machine (macbook pro 15 2018 and macbook air 15 M2) are on Mac OS Sonoma and is blocking my work with this problem((

when I try to rollback on macbook air 15 m2 it shows me message like this (and something simular with macbook pro 15 2018):

Hi - there is a workaround documented for this in the latest Docker release notes, which I found after updating to the latest Docker. I'm on an M2-Mac and changing the property in docker settings worked immediately. Note that although it says to 'add' the config line in the release notes, the config line is already there, and in my case I just had to change the property from true to false and it worked.

Known Issues: For Mac

Creating a container with the port 53 fails with the error address already in use. As a workaround, deactivate network acceleration by adding "kernelForUDP": false, in the settings.json file located at ~/Library/Group Containers/group.com.docker/settings.json_

Source: https:// docs.docker.com/desktop/release-notes/#known-issues (apple won't let me post the actual link... take out the spaces and you can navigate there)

Thanks for helping out here.

Regrading this:

apple won't let me post the actual link

I’m able to post the link just fine:

https://docs.docker.com/desktop/release-notes/#known-issues

You just have to do it in the clear, per tip 14 in Quinn’s Top Ten DevForums Tips.

Did that not work for you?

Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"

Thanks @eskimo , I'm new to the forum and didn't realize that was the proper format. I appreciate the tip! In any case, I hope the fix works for everyone as it did for me!