A SRV record has the form: An example SRV record in textual form that might be found in a zone file might be the following: This points to a server named sipserver.example.com listening on TCP port 5060 for Session Initiation Protocol (SIP) protocol services.
The first three records share a priority of 10, so the weight field's value will be used by clients to determine which server (host and port combination) to contact.
The load balancing provided by SRV records is inherently limited since the information is essentially static.
SRV records are also used by Outlook 2007, 2010 and Macintosh 10.6 mail to locate the Exchange Autodiscover service.
[23] A registry of service names for SRV records & protocols is maintained by the Internet Assigned Numbers Authority (IANA) as defined in RFC 6335.