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mdnsd(8) [netbsd man page]

MDNSD(8)						    BSD System Manager's Manual 						  MDNSD(8)

NAME
mdnsd -- Multicast and Unicast DNS daemon SYNOPSIS
mdnsd DESCRIPTION
mdnsd (also known as mDNSResponder on some systems) is a daemon invoked at boot time to implement Multicast DNS and DNS Service Discovery. On Mac OS X 10.6 (Snow Leopard), mdnsd is also the system-wide Unicast DNS Resolver. mdnsd listens on UDP port 5353 for Multicast DNS Query packets. When it receives a query for which it knows an answer, mdnsd issues the appropriate Multicast DNS Reply packet. mdnsd also performs Unicast and Multicast DNS Queries on behalf of client processes, and maintains a cache of the replies. mdnsd has no user-specifiable command-line argument, and users should not run mdnsd manually. LOGGING There are several methods with which to examine mdnsd's internal state for debugging and diagnostic purposes. The syslogd(8) logging levels map as follows: Error - Error messages Warning - Client-initiated operations Notice - Sleep proxy operations Info - Informational messages By default, only log level Error is logged. A SIGUSR1 signal toggles additional logging, with Warning and Notice enabled by default: # pkill -USR1 mdnsd A SIGUSR2 signal toggles packet logging: # pkill -USR2 mdnsd A SIGINFO signal will dump a snapshot summary of the internal state to /var/log/system.log: # pkill -INFO mdnsd FILES
/usr/sbin/mdnsd SEE ALSO
dns-sd(1), pkill(1), syslogd(8) For information on Multicast DNS, see http://www.multicastdns.org/ For information on DNS Service Discovery, see http://www.dns-sd.org/ For information on how to use the Multicast DNS and the DNS Service Discovery APIs on Mac OS X and other platforms, see http://developer.apple.com/bonjour/ For the source code to mdnsd, see http://developer.apple.com/darwin/projects/bonjour/ HISTORY
The mdnsd daemon first appeared in Mac OS X 10.2 (Jaguar). Also available from the Darwin open source repository (though not officially supported by Apple) are mdnsd daemons for other platforms, including Mac OS 9, Microsoft Windows, Linux, FreeBSD, NetBSD, Solaris, and other POSIX systems. BUGS
mdnsd bugs are tracked in Apple Radar component "mDNSResponder". BSD
February 27, 2011 BSD

Check Out this Related Man Page

dns-sd(1)						    BSD General Commands Manual 						 dns-sd(1)

NAME
dns-sd -- Multicast DNS (mDNS) & DNS Service Discovery (DNS-SD) Test Tool SYNOPSIS
dns-sd -R name type domain port [key=value ...] dns-sd -B type domain dns-sd -L name type domain DESCRIPTION
The dns-sd command is a network diagnostic tool, much like ping(8) or traceroute(8). However, unlike those tools, most of its functionality is not implemented in the dns-sd executable itself, but in library code that is available to any application. The library API that dns-sd uses is documented in /usr/include/dns_sd.h. The dns-sd command is primarily intended for interactive use. Because its command-line arguments and output format are subject to change, invoking it from a shell script will generally be fragile. Additionally, the asynchronous nature of DNS Service Discovery does not lend itself easily to script-oriented programming. For example, calls like "browse" never complete; the action of performing a "browse" sets in motion machinery to notify the client whenever instances of that service type appear or disappear from the network. These notifications con- tinue to be delivered indefinitely, for minutes, hours, or even days, as services come and go, until the client explicitly terminates the call. This style of asynchronous interaction works best with applications that are either multi-threaded, or use a main event-handling loop to receive keystrokes, network data, and other asynchronous event notifications as they happen. If you wish to perform DNS Service Discovery operations from a scripting language, then the best way to do this is not to execute the dns-sd command and then attempt to decipher the textual output, but instead to directly call the DNS-SD APIs using a binding for your chosen lan- guage. For example, if you are programming in Ruby, then you can directly call DNS-SD APIs using the dnssd package documented at <http://rubyforge.org/projects/dnssd/>. Similar bindings for other languages are also in development. dns-sd -R name type domain port [key=value ...] register (advertise) a service in the specified domain with the given name and type as listening (on the current machine) on port. name can be arbitrary unicode text, containing any legal unicode characters (including dots, spaces, slashes, colons, etc. without restriction), up to 63 UTF-8 bytes long. type must be of the form "_app-proto._tcp" or "_app-proto._udp", where "app-proto" is an appli- cation protocol name registered at http://www.dns-sd.org/ServiceTypes.html. domain is the domain in which to register the service. In current implementations, only the local multicast domain "local" is supported. In the future, registering will be supported in any arbitrary domain that has a working DNS Update server [RFC 2136]. The domain "." is a synonym for "pick a sensible default" which today means "local". port is a number from 0 to 65535, and is the TCP or UDP port number upon which the service is listening. Additional attributes of the service may optionally be described by key/value pairs, which are stored in the advertised service's DNS TXT record. Allowable keys and values are listed with the service registration at http://www.dns-sd.org/ServiceTypes.html. dns-sd -B type domain browse for instances of service type in domain. For valid types see http://www.dns-sd.org/ServiceTypes.html as described above. Omitting the domain or using "." means "pick a sensible default." dns-sd -L name type domain look up and display the information necessary to contact and use the named service: the hostname of the machine where that service is available, the port number on which the service is listening, and (if present) TXT record attributes describing properties of the service. Note that in a typical application, browsing happens rarely, while lookup (or "resolving") happens every time the service is used. For example, a user browses the network to pick a default printer fairly rarely, but once a default printer has been picked, that named ser- vice is resolved to its current IP address and port number every time the user presses Cmd-P to print. EXAMPLES
To advertise the existence of LPR printing service on port 515 on this machine, such that it will be discovered by the Mac OS X printing software and other DNS-SD compatible printing clients, use: dns-sd -R "My Test" _printer._tcp. . 515 pdl=application/postscript For this registration to be useful, you need to actually have LPR service available on port 515. Advertising a service that does not exist is not very useful, and will be confusing and annoying to other people on the network. Similarly, to advertise a web page being served by an HTTP server on port 80 on this machine, such that it will show up in the Bonjour list in Safari and other DNS-SD compatible Web clients, use: dns-sd -R "My Test" _http._tcp . 80 path=/path-to-page.html To find the advertised web pages on the local network (the same list that Safari shows), use: dns-sd -B _http._tcp While that command is running, in another window, try the dns-sd -R example given above to advertise a web page, and you should see the "Add" event reported to the dns-sd -B window. Now press Ctrl-C in the dns-sd -R window and you should see the "Remove" event reported to the dns-sd -B window. FILES
/usr/bin/dns-sd SEE ALSO
mdnsd(8) HISTORY
The dns-sd command first appeared in NetBSD 6.0, having originated in Mac OS X 10.4 (Tiger). NetBSD June 2, 2019 NetBSD
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