Wrong host in _device-info._tcp (AVAHI) using macvlan networking

[chrisridd]

What I see

Browsing macOS 15.3 Finder's "Networks" shows an entry called "files". Double-clicking it fails to connect.

Using Finder's "Go to server" I can use the correct URL for my Samba container, which opens, and adds another entry called "files.local" (with the TimeCapsule icon) into Finder's "Networks".

What I expected

I expected "Networks" to list my Samba container with the TimeCapsule icon, and for opening it to succeed and show the list of shares.

More info

My docker host is called portainer.local, and my Samba container using macvlan networking is called files.local. The entrypoint.sh script is writing this samba.service:

<?xml version="1.0" standalone='no'?>
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">
<service-group>
 <name replace-wildcards="yes">files</name>
 <service>
   <type>_smb._tcp</type>
   <port>445</port>
 </service>

 <service>
  <type>_device-info._tcp</type>
  <port>0</port>
  <txt-record>model=TimeCapsule</txt-record>
 </service>

 <service>
  <type>_adisk._tcp</type>
  <txt-record>sys=waMa=0,adVF=0x100</txt-record>
  <txt-record>dk0=adVN=TimeMachine,adVF=0x82</txt-record>
 </service>
</service-group>

Wild guess

I think <hostname> needs to go in the _device-info._tcp section. Maybe the others too? Currently the dns-sd tool in macOS outputs the portainer address, which may explain the failure to connect.

$ dns-sd -L files _device-info._tcp 
Lookup files._device-info._tcp.local
DATE: ---Sat 01 Feb 2025---
14:17:14.671  ...STARTING...
14:17:15.102  files._device-info._tcp.local. can be reached at portainer.local.:0 (interface 14)
 model=TimeCapsule

But I don't really understand what's happening or what Finder is expecting.

[MarvAmBass]

Hi there,

keep in mind that the zeroconf might be a bit hacky - it usually works only within a network and is not routable.

For me it usually works with both - I see the hostname and the pretty configured name with it's icon.

If you want to be sure, install avahi on your dockerhost and make a explicit configuration of your configuration.

I just checked, I have both in finder and both seem to work.

[chrisridd]

I agree, zeroconf is only going to work on the LAN, which is fine. I'm apparently seeing all the published records so that part seems "OK".

I am using the example compose template, which does appear to create that samba.service file on the docker host, so must be relying on the host to publish the records, explaining the unexpected hostname. I was expecting the samba container to be publishing the service instead..

So removing the volume mapping '/etc/avahi/services/:/external/avahi' and the now bogus samba.service from the docker host (and reloading its avahi-service), does fix the dns-sd output.

Unfortunately I'm still getting 'files' (an iMac icon) in "Networks", which still does not open. Again, "go to server" with files.local works (and adds a server with the expected custom icon.) Maybe there's some stale stuff in Networks; I'm not sure how to debug that though except by rebooting the Mac. Which is kind of a 🔨 .

[chrisridd]

I rebooted the Mac.

One icon now in Networks, matches the one specified by Samba, and opening it works.

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