Dns Query Setting - Aastra BLUESTAR 8000I Pbx-Mode Administrator Manual

DNS Query Setting

Parameter–
sip dns query type
Description
Format
Default Value
Range
Example
41-001390-00 Rev 02 – 12.2011
Configuration Files –
aastra.cfg, <model>.cfg, <mac>.cfg
Specifies the Domain Name Service (DNS) query method to use when the BluStar
8000i performs a DNS lookup.
Integer
1
0 A only - The BluStar 8000i issues requests for "A" (Host IP Address) records
from the DNS server to get the IP address, and uses the default port number of
5060.
1 SRV & A - The BluStar 8000i issues requests for "SRV" (Service Location
Record) records from the DNS server to get the port number. Most often, the IP
address is included in the response from the DNS server to avoid extra queries. If
there is no IP address returned in the response, the BluStar 8000i sends out the
request for "A" records from the DNS server to find the IP address.
2 NAPTR & SRV & A - First, the BluStar 8000i sends "NAPTR" (Naming Authority
Pointer) lookup to get the "SRV" pointer and service type. For example, if Global
SIP transport protocol on the BluStar 8000i is "UDP", and Proxy server on the BluS-
tar 8000i is "test.aastra.com", then:
1. If the NAPTR record is returned empty, the BluStar 8000i will use the default
value "_sip._udp.test.aastra.com" for the "SRV" lookup.
2. If the NAPTR record is returned "test.aastra.com SIP+D2U ...._sip._udp.abc.aas-
tra.com", the BluStar 8000i will use "_sip._udp.abc.aastra.com" for the "SRV"
lookup.
3. If the NAPTR record is returned "test.aastra.com SIP+D2T ...._sip._tcp.test.aas-
tra.com", where the service type TCP mismatches the BluStar 8000i configured
transport protocol "UDP", the BluStar 8000i will ignore this value and use the
default value "_sip._udp.test.aastra.com" for the "SRV" lookup.
Note: The BluStar 8000i does not use the service type sent by the NAPTR
response to switch its transport protocol, nor does it use the NAPTR response to
determine whether to use a secure or unsecure communication path. The BluStar
8000i will always use a global sip protocol that is configured on the BluStar 8000i
via configuration files.
After performing NAPTR, the BluStar 8000i sends "SRV" lookup to get the IP
address and port number. If there is no IP address in the "SRV" response, then it
sends out an "A" lookup to get it.
sip dns query type: 2
Advanced Operational Parameters
A-46