Aastra 9000i Series Administrator's Manual page 236

SIP Server (SRV) Lookup
The SIP SRV Lookup feature allows you to configure the IP phone to issue a DNS query to
retrieve records pertaining to a SIP proxy, a SIP registrar, or a SIP outbound proxy.
The IP phone issues a DNS query for an SRV record when the IP address of the server is FQDN
and the corresponding port is 0.
For example, if the phone is configured with sip proxy ip of "ana.aastra.com", and sip proxy
port of "0", the SRV lookup may return multiple servers, based on the priorities if one is selected
as primary and others are selected as secondary. However, if the IP address is an FQDN and the
corresponding server port is non-zero, then the phone issues a DNS "A" Name Query to resolve
the FQDN into dot notation form.
If the IP address is a valid dot notation and the port is zero, then a default port 5060 is used.
You can configure SRV lookup using the configuration files (aastra.cfg and <mac>.cfg) only. The
parameters to use are:
• sip proxy ip
• sip proxy port
41-001343-01 Rev 02, Release 3.2.2
Note: The phones only generate a 'request' and do not facilitate the
'DNS or SRV service or provide a response to the requests.
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