1 .\" -*- tab-width: 4 -*-
3 .\" Copyright (c) 2004 Apple Computer, Inc. All Rights Reserved.
5 .\" Licensed under the Apache License, Version 2.0 (the "License");
6 .\" you may not use this file except in compliance with the License.
7 .\" You may obtain a copy of the License at
9 .\" http://www.apache.org/licenses/LICENSE-2.0
11 .\" Unless required by applicable law or agreed to in writing, software
12 .\" distributed under the License is distributed on an "AS IS" BASIS,
13 .\" WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 .\" See the License for the specific language governing permissions and
15 .\" limitations under the License.
17 .\" Copyright 2016 Toomas Soome <tsoome@me.com>
19 .Dd Jan 28, 2016 \" Date
20 .Dt DNS-SD 1M \" Document Title
21 .Os illumos \" Operating System
25 .Nd Multicast DNS (mDNS) & DNS Service Discovery (DNS-SD) Test Tool \" For whatis
35 .Op Fl R Ar name type domain port Op Ar key=value ...
38 .Op Fl B Ar type domain
41 .Op Fl L Ar name type domain
44 .Op Fl P Ar name type domain port host IP Op Ar key=value ...
47 .Op Fl q Ar name rrtype rrclass
50 .Op Fl Z Ar type domain
53 .Op Fl G Ns \ v4/v6/v4v6 Ar name
61 command is a network diagnostic tool, much like
65 However, unlike those tools, most of its functionality is not implemented in the
67 executable itself, but in library code that is available to any application.
71 .Pa /usr/include/dns_sd.h .
74 command replaces the older
80 command is primarily intended for interactive use.
81 Because its command-line arguments and output format are subject to change,
82 invoking it from a shell script will generally be fragile.
83 Additionally, the asynchronous nature of DNS Service Discovery does
84 not lend itself easily to script-oriented programming.
85 For example, calls like "browse" never complete; the action of performing a
86 "browse" sets in motion machinery to notify the client whenever instances of
87 that service type appear or disappear from the network.
88 These notifications continue to be delivered indefinitely, for minutes,
89 hours, or even days, as services come and go, until the client
90 explicitly terminates the call.
91 This style of asynchronous interaction works best with applications that are
92 either multi-threaded, or use a main event-handling loop to receive keystrokes,
93 network data, and other asynchronous event notifications as they happen.
95 If you wish to perform DNS Service Discovery operations from a
96 scripting language, then the best way to do this is not to execute the
98 command and then attempt to decipher the textual output, but instead to
99 directly call the DNS-SD APIs using a binding for your chosen language.
101 For example, if you are programming in Ruby, then you can
102 directly call DNS-SD APIs using the dnssd package documented at
103 .Pa <http://rubyforge.org/projects/dnssd/> .
105 Similar bindings for other languages are also in development.
108 return a list of domains recommended for registering(advertising) services.
110 return a list of domains recommended for browsing services.
112 Normally, on your home network, the only domain you are likely to see is
114 However if your network administrator has created Domain Enumeration records,
115 then you may also see other recommended domains for registering and browsing.
116 .It Nm Fl R Ar name type domain port Op Ar key=value ...
117 register (advertise) a service in the specified
123 as listening (on the current machine) on
127 can be arbitrary unicode text, containing any legal unicode characters
128 (including dots, spaces, slashes, colons, etc. without restriction),
129 up to 63 UTF-8 bytes long.
131 must be of the form "_app-proto._tcp" or "_app-proto._udp", where
132 "app-proto" is an application protocol name registered at
133 .Pa http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xml .
136 is the domain in which to register the service.
137 In current implementations, only the local multicast domain "local" is
139 In the future, registering will be supported in any arbitrary domain that has a
140 working DNS Update server [RFC 2136].
143 "." is a synonym for "pick a sensible default" which today
147 is a number from 0 to 65535, and is the TCP or UDP port number upon
148 which the service is listening.
150 Additional attributes of the service may optionally be described by
151 key/value pairs, which are stored in the advertised service's DNS TXT
153 Allowable keys and values are listed with the service registration at
154 .Pa http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xml .
155 .It Nm Fl B Ar type domain
156 browse for instances of service
164 .Pa http://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xml .
168 or using "." means "pick a sensible default."
169 .It Nm Fl L Ar name type domain
170 look up and display the information necessary to contact and use the
171 named service: the hostname of the machine where that service is
172 available, the port number on which the service is listening, and (if
173 present) TXT record attributes describing properties of the service.
175 Note that in a typical application, browsing may only happen rarely, while
176 lookup (or "resolving") happens every time the service is used.
177 For example, a user browses the network to pick a default printer fairly rarely,
178 but once a default printer has been picked, that named service is resolved to
179 its current IP address and port number every time the user presses Cmd-P to
181 .It Nm Fl P Ar name type domain port host IP Op Ar key=value ...
182 create a proxy advertisement for a service running on(offered by) some other
184 The two new options are Host, a name for the device and IP, the address of it.
186 The service for which you create a proxy advertisement does not necessarily have
187 to be on your local network.
188 You can set up a local proxy for a website on the Internet.
189 .It Nm Fl q Ar name rrtype rrclass
190 look up any DNS name, resource record type, and resource record class,
191 not necessarily DNS-SD names and record types.
192 If rrtype is not specified, it queries for the IPv4 address of the name,
193 if rrclass is not specified, IN class is assumed.
194 If the name is not a fully qualified domain name, then search domains may be
196 .It Nm Fl Z Ar type domain
197 browse for service instances and display output in zone file format.
198 .It Nm Fl G Ns \ v4/v6/v4v6 Ar name
199 look up the IP address information of the name.
200 If v4 is specified, the IPv4 address of the name is looked up,
201 if v6 is specified the IPv6 address is looked up.
202 If v4v6 is specified both the IPv4 and IPv6 address is looked up.
203 If the name is not a fully qualified domain name, then search domains may be
206 return the version of the currently running daemon/system service.
209 .Pa /usr/bin/dns-sd \" Pathname
212 To advertise the existence of LPR printing service on port 515 on this
213 machine, such that it will be discovered by the Mac OS X printing software
214 and other DNS-SD compatible printing clients, use:
216 .Dl Nm Fl R Ns \ \&"My Test\&" _printer._tcp. \&. 515 pdl=application/postscript
218 For this registration to be useful, you need to actually have LPR service
219 available on port 515.
220 Advertising a service that does not exist is not very useful, and will be
221 confusing and annoying to other people on the network.
223 Similarly, to advertise a web page being served by an HTTP
224 server on port 80 on this machine, such that it will show up in the
225 Bonjour list in Safari and other DNS-SD compatible Web clients, use:
227 .Dl Nm Fl R Ns \ \&"My Test\&" _http._tcp \&. 80 path=/path-to-page.html
229 To find the advertised web pages on the local network (the same list that
232 .Dl Nm Fl B Ns \ _http._tcp
234 While that command is running, in another window, try the
236 example given above to advertise a web page, and you should see the
237 "Add" event reported to the
240 Now press Ctrl-C in the
242 window and you should see the "Remove" event reported to the
246 In the example below, the www.apple.com web page is advertised as a service
248 running on a target host called apple.local, which resolves to 17.149.160.49.
250 .Dl Nm Fl P Ns \ apple _http._tcp \&"\&"\& 80 apple.local 17.149.160.49
252 The Bonjour menu in the Safari web browser will now show "apple".
253 The same IP address can be reached by entering apple.local in the web browser.
254 In either case, the request will be resolved to the IP address and browser will
255 show contents associated with www.apple.com.
257 If a client wants to be notified of changes in server state, it can
258 initiate a query for the service's particular record and leave it running.
259 For example, to monitor the status of an iChat user you can use:
261 .Dl Nm Fl q Ns \ someone@ex1._presence._tcp.local txt
263 Everytime status of that user(someone) changes, you will see a new TXT record
266 You can also query for a unicast name like www.apple.com and monitor its status.
268 .Dl Nm Fl q Ns \ www.apple.com
269 .Sh INTERFACE STABILITY