dns-sd(1M) System Administration Commands dns-sd(1M)NAMEdns-sd - Multicast DNS (mDNS) & DNS Service Discovery (DNS-SD) Test
Tool
SYNOPSISdns-sd-R name type domain port [key=value ...]
dns-sd-B type domain
dns-sd-L name type domain
dns-sd-Q FQDN rrtype rrclass
dns-sd-C FQDN rrtype rrclass
dns-sd-P name type domain port host IP [key=value ...]
dns-sd-E | -F | -A | -U | -N | -T | -M | -I
DESCRIPTION
The dns-sd command is a network diagnostic tool, much like ping(1M) or
traceroute(1M). 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 can be unpredictable. Additionally, the
asynchronous nature of DNS Service Discovery does not easily lend
itself to script-oriented programming. This style of asynchronous
interaction works best with applications that are either multi-
threaded, or use a main event-handling loop to receive keystrokes, net‐
work data, and other asynchronous event notifications as they happen.
OPTIONS
The following options are supported:
-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 the
specified port.
name can be any arbitrary unicode text, containing any legal uni‐
code characters (including dots, spaces, slashes, colons, and so on
without any restrictions), 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 application 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 sup‐
ported. In the future, registering will be supported in any arbi‐
trary domain that has a working DNS Update server [RFC 2136]. The
domain "." is a synonym for "pick a sensible default", which cur‐
rently means "local".
port is a number from 0 to 65535, and is the TCP or UDP port number
upon which the service is listening. Registering a service on port
0 allows an application to explicitly advertise the non-availabil‐
ity of a service.
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
-B type domain
Browse for instances of service type in domain.
For valid types, see http://www.dns-sd.org/ServiceTypes.html. Omit‐
ting the domain name or using "." means "pick a sensible default."
-L name type domain
Look up and display the information necessary to contact and use
the named service. This information includes 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.
In a typical application, browsing happens rarely, while lookup (or
"resolving") happens every time the service is used. For example, a
user does not browse the network to pick a default printer that
often, 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.
-Q FQDN rrtype rrclass
Generic query for any resource record type and class.
-C FQDN rrtype rrclass
Generic query for any resource record type and class. This option
also reconfirms each result from the query. Reconfirming the record
instructs mdnsd(1M) to verify the validity of the record. If the
record is not valid mdnsd(1M) flushes the record from the daemon's
cache and also from other mdnsd(1M) caches on the network.
-P name type domain port host IP [key=value ...]
Register (advertise) a service in the specified domain with the
given name and type listening on the specified port and accessible
on another host. This option should be used to advertise by proxy a
service accessible on another host. The host name and IPv4 address
to access the service must be specified.
-E
Discover recommended registration domains. This option returns the
recommended domains to register a service. The recommended regis‐
tration domains are returned by querying the name servers in
resolv.conf(4).
-F
Discover recommended browsing domains. This option returns the rec‐
ommended domains for browsing services. The recommended browsing
domains are returned by querying the name servers in
resolv.conf(4).
-A
Test registering service with Multicast DNS and test the add,
update and delete operations of DNS records with Multicast DNS.
-U
Test registering service with Multicast DNS and test updating of
DNS TXT records for a service registered with Multicast DNS.
-N
Test adding a large NULL record for a service registered with Mul‐
ticast DNS.
-T
Test adding a large TXT record for a service registered with Multi‐
cast DNS.
-M
Test creating a registration with multiple TXT records.
-I
Test registering and then immediately updating a TXT record.
EXAMPLES
Example 1 Advertising a printing service
The following command advertises the existence of LPR printing service
on port 515 on this machine, so that it will be available to DNS-SD
compatible printing clients:
dns-sd-R "My Test" _printer._tcp. . 515 pdl=application/postscript
For this registration to be useful, the LPR service should be available
on port 515. Advertising a service that does not exist is not very use‐
ful.
Example 2 Advertising a web page
The following command advertises a web page being served by an HTTP
server on port 80 on this machine, so that it will appear on the Bon‐
jour list in Safari and other DNS-SD compatible Web clients:
dns-sd-R "My Test" _http._tcp . 80 path=/path-to-page.html
Example 3 Finding the advertised web pages on the local network
The following command finds the advertised web pages on the local net‐
work (the same list that Safari shows):
dns-sd-B _http._tcp
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │service/network/dns/mdns │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Volatile │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOmdnsd(1M), ping(1M), traceroute(1M), resolv.conf(4), attributes(5)SunOS 5.11 21 Aug 2007 dns-sd(1M)
