How can my guest, on her Mac, see my shared music library using "Share Music With Guests"?

Solution 1:

Many routers prevent discovery between clients. A quick way to make sure it’s not the router configuration blocking discovery would be to connect your computers directly with an Ethernet cable or temporarily connect your Mac to the router with Ethernet and share your internet over wifi. Connect your guest computer to your wifi sharing on your Mac.

• https://support.apple.com/en-euro/guide/mac-help/mchlp1540/mac

You want to share Ethernet over wifi. Don’t try to connect to wifi and share out wifi per the warning to not try to connect and share over Ethernet. (Both pretty much guarantee you configure multiple DHCP servers on the same network segment)

Assuming the music sharing works over point to point network or sharing wifi, you’ll need the wifi network admin to fix things. If it doesn’t work, you might need to work on firewalls and why the second app doesn’t see your shared library.

• https://support.apple.com/en-euro/guide/music/muscadf6038/mac

As to the nitty gritty, on recent macOS with media sharing controlled from a system preference pane - you can choose a sharing name and see the service turn on and off in real time from any Mac on the network segment.

dns-sd -B _daap

When you're done press and hold the control key and while it's down, the C key once to exit the dns service delivery browse command.

Home sharing uses the _home-sharing._tcp. service instead of _daap._tcp. that guest sharing does.

bmike@m1 ~ % dns-sd -B _daap
Browsing for _daap._tcp
DATE: ---Thu 30 Dec 2021---
10:33:46.256  ...STARTING...
Timestamp     A/R    Flags  if Domain               Service Type         Instance Name
10:33:46.257  Add        3   6 local.               _daap._tcp.          dev library
10:33:46.257  Add        2  12 local.               _daap._tcp.          dev library