1.\" $NetBSD: mdnsd.8,v 1.3 2011/02/27 14:01:42 wiz Exp $ 2.\" 3.\" -*- tab-width: 4 -*- 4.\" 5.\" Copyright (c) 2003-2004 Apple Computer, Inc. All Rights Reserved. 6.\" 7.\" Licensed under the Apache License, Version 2.0 (the "License"); 8.\" you may not use this file except in compliance with the License. 9.\" You may obtain a copy of the License at 10.\" 11.\" http://www.apache.org/licenses/LICENSE-2.0 12.\" 13.\" Unless required by applicable law or agreed to in writing, software 14.\" distributed under the License is distributed on an "AS IS" BASIS, 15.\" WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 16.\" See the License for the specific language governing permissions and 17.\" limitations under the License. 18.\" 19.\" Log: mDNSResponder.8,v $ 20.\" Revision 1.10 2009/04/20 16:12:13 mcguire 21.\" <rdar://problem/6807798> manpage: roff errors 22.\" 23.\" Revision 1.9 2009/04/11 00:20:27 jessic2 24.\" <rdar://problem/4426780> Daemon: Should be able to turn on LogOperation dynamically 25.\" 26.\" Revision 1.8 2006/10/06 17:31:33 mkrochma 27.\" <rdar://problem/4769407> Typo in man page for mDNSResponder(8) 28.\" 29.\" Revision 1.7 2006/08/14 23:24:56 cheshire 30.\" Re-licensed mDNSResponder daemon source code under Apache License, Version 2.0 31.\" 32.\" Revision 1.6 2005/02/10 22:35:28 cheshire 33.\" <rdar://problem/3727944> Update name 34.\" 35.\" Revision 1.5 2004/06/29 02:41:38 cheshire 36.\" Add note that mDNSResponder is called mdnsd on some systems 37.\" 38.\" Revision 1.4 2004/05/18 18:14:36 cheshire 39.\" Minor wording update 40.\" 41.\" Revision 1.3 2004/04/22 02:56:08 cheshire 42.\" <rdar://problem/3619494>: mDNSResponder man page format error 43.\" 44.\" Revision 1.2 2004/04/12 18:03:24 ksekar 45.\" <rdar://problem/3619494>: mDNSResponder man page format error 46.\" 47.\" Revision 1.1 2003/11/13 03:21:38 cheshire 48.\" <rdar://problem/3086886>: No man page for mDNSResponder 49.\" 50.\" 51.\" 52.Dd February 27, 2011 53.Dt MDNSD 8 54.Os 55.\" 56.Sh NAME 57.Nm mdnsd 58.Nd Multicast and Unicast DNS daemon \" Name Description for whatis database 59.\" 60.Sh SYNOPSIS 61.Nm 62.\" 63.Sh DESCRIPTION 64.Nm 65(also known as 66.Nm mDNSResponder 67on some systems) 68is a daemon invoked at boot time to implement Multicast DNS and DNS Service Discovery. 69On 70Mac OS X 10.6 (Snow Leopard), 71.Nm 72is also the system-wide Unicast DNS Resolver. 73.Pp 74.Nm 75listens on UDP port 5353 for Multicast DNS Query packets. 76When it receives a query for which it knows an answer, 77.Nm 78issues the appropriate Multicast DNS Reply packet. 79.Pp 80.Nm 81also performs Unicast and Multicast DNS Queries on behalf of client processes, and 82maintains a cache of the replies. 83.Pp 84.Nm 85has no user-specifiable command-line argument, and users should not run 86.Nm 87manually. 88.Ss LOGGING 89There are several methods with which to examine 90.Nm Ap s 91internal state for debugging and diagnostic purposes. 92The 93.Xr syslogd 8 94logging levels map as follows: 95.Pp 96.Dl Error - Error messages 97.Dl Warning - Client-initiated operations 98.Dl Notice - Sleep proxy operations 99.Dl Info - Informational messages 100.Pp 101By default, only log level Error is logged. 102.Pp 103A SIGUSR1 signal toggles additional logging, with Warning and Notice 104enabled by default: 105.Pp 106.Dl # pkill -USR1 mdnsd 107.Pp 108A SIGUSR2 signal toggles packet logging: 109.Pp 110.Dl # pkill -USR2 mdnsd 111.Pp 112A SIGINFO signal will dump a snapshot summary of the internal state to 113.Pa /var/log/system.log : 114.Pp 115.Dl # pkill -INFO mdnsd 116.Sh FILES 117.Pa /usr/sbin/mdnsd \" Pathname 118.\" 119.Sh SEE ALSO 120.Xr dns-sd 1 , 121.Xr pkill 1 , 122.Xr syslogd 8 123.Pp 124For information on Multicast DNS, see 125.Pa http://www.multicastdns.org/ 126.Pp 127For information on DNS Service Discovery, see 128.Pa http://www.dns-sd.org/ 129.Pp 130For information on how to use the Multicast DNS and the 131DNS Service Discovery APIs on Mac OS X and other platforms, see 132.Pa http://developer.apple.com/bonjour/ 133.Pp 134For the source code to 135.Nm , see 136.Pa http://developer.apple.com/darwin/projects/bonjour/ 137.\" 138.Sh HISTORY 139The 140.Nm 141daemon first appeared in Mac OS X 10.2 (Jaguar). 142.Pp 143Also available from the Darwin open source repository 144(though not officially supported by Apple) are 145.Nm 146daemons for other platforms, including Mac OS 9, Microsoft Windows, 147Linux, 148.Fx , 149.Nx , 150Solaris, and other POSIX systems. 151.\" 152.Sh BUGS 153.Nm 154bugs are tracked in Apple Radar component "mDNSResponder". 155