How DNS-SD functions
Before you configure your DNS server, you should clearly understand how the process works:
1. When a device gets an address from your DHCP server, your DHCP server also includes information specifying a default DNS domain. In this case, “example.com.”
2. The device needs to determine whether you’d like it to use wide-area DNS-SD to browse for services. It does this by prepending the text “
lb._dns-sd._udp” to the default DNS domain and then doing a query for PTR records with that name (in this case “
3. In the example, the device’s query gets an answer: “example.com.” In principle, the PTR record could indicate some other domain to browse instead, but in the common case, a self-referential PTR referring back to the same domain is usually easiest.
4. The device now knows it’s supposed to browse for services in “example.com.” Any time an app like Safari calls one of the DNS-SD browsing APIs to browse for services (without explicitly specifying a particular DNS domain to browse), the mdnsd daemon automatically browses the default browse domain it learned from the network.
You can also advertise:
Printers that appear in the print dialog of a Mac and in the Printer Setup Wizard in Bonjour for Windows.
SSH servers that appear in Terminal’s Connect to Server window.
A shared Photos album of pictures that appears in Photo’s sidebar.
For the current list of service types, see DNS SRV (RFC 2782) Service Types on the DNS Service Discovery (DNS-SD) website.