avahi.service man page
avahi.service — avahi-daemon static service file
/etc/avahi/services/*.service are XML fragments containing static DNS-SD service data. Every service file can contain multiple service definitions which share the same name. This is useful for publishing service data for services which implement multiple protocols. (i.e. a printer implementing _ipp._tcp and _printer._tcp)
<service-group> The document tag of avahi service files. Should contain one <name> and one or more <service> elements.
<name replace-wildcards="yes|no"> The service name. If replace-wildcards is "yes", any occurence of the string "%h" will be replaced by the local host name. This can be used for service names like "Remote Terminal on %h". If replace-wildcards is not specified, defaults to "no".
<service protocol="ipv4|ipv6|any"> Contains the service information for exactly one service type. Should contain one <type> and one <port> element. Optionally it may contain one <domain-name>, one <host-name>, any number of <subtype> and any number of <txt-record> elements. The attribute protocol specifies the protocol to advertise the service on. If any is used (which is the default), the service will be advertised on both IPv4 and IPv6.
<type> Contains the DNS-SD service type for this service. e.g. "_http._tcp".
<subtype> Contains an additional DNS-SD service subtype for this service. e.g. "_anon._sub._ftp._tcp".
<domain-name> The domain name this service should be registered. If omited defaults to the default domain of the avahi daemon. (probably .local)
<host-name> The host name of the host that provides this service. This should be a host that is resolvable by multicast or unicast DNS. Please note that you need to specify a fully-qualified domain name (FQDN) here, i.e. .local is not appended implicitly! The host name doesn't need to be part of the domain specified in <domain-name>. See avahi.hosts(5) for more information how to publish additional host name mappings.
<port> The IP port number the service listens on.
<txt-record> DNS-SD TXT record data.
The Avahi Developers <avahi (at) lists (dot) freedesktop (dot) org>; Avahi is available from http://avahi.org/