Dns Configuration; Overview; Verifying The Srv Record; Microsoft Dns Server - Cisco TelePresence Administrator's Manual

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DNS configuration

Overview

This section gives examples of DNS configuration using
Microsoft DNS Server and BIND 8 & 9.
These examples show how to set up an SRV record to handle
H.323 URIs of the form user@example.com. These are handled
by the system with the fully qualified domain name of vcs.
example.com which is listening on port 1719, the default
registration port.
It is assumed that both A and AAAA records already exist
for vcs.example.com. If not, you will need to add one.

Verifying the SRV record

There are a range of tools available to investigate DNS records.
One commonly found on Microsoft Windows and UNIX platforms
is nslookup. Use this to verify that everything is working as
expected.
For example:
nslookup -querytype=srv _ h323ls. _ udp.
•
example.com
and check the output.
Overview and System
Introduction
status configuration
D14049.08
November 2010
Using Microsoft DNS Server you can add the SRV record using either the command line or the MMC snap-in.
To use the command line, on the DNS server open a command window and enter:
dnscmd . /RecordAdd domain service _ name SRV Priority Weight Port Target
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where:
domain
is the domain into which you wish to insert the record
service _ name
is the name of the service you're adding
Priority
is the priority as defined by
Weight
is the weight as defined by
Port
is the port on which the system hosting the domain is listening
Target
is the FQDN of the system hosting the domain
For example:
dnscmd . /RecordAdd example.com _ h323ls. _ udp SRV 1 0 1719 vcs.example.com
•
BIND is a commonly used DNS server on UNIX and Linux systems. Configuration is based around two sets of text files: named.conf
which describes which zones are represented by the server, and a selection of zone files which describe the detail of each zone.
BIND is sometimes run chrooted for increased security. This gives the program a new root directory, which means that the
configuration files may not appear where you expect them to be. To see if this is the case on your system, run
ps aux | grep named
•
This will give the command line that named (the BIND server) was invoked with. If there is a -t option, then the path following that is
the new root directory and your files will be located relative to that root.
In /etc/named.conf look for a directory entry within the options section. This will give the directory in which the zone files are
stored, possibly relative to a new root directory. In the appropriate zone section, a file entry will give the name of the file containing the
zone details.
For more details of how to configure BIND servers and the DNS system in general see the publication
Cisco VCS Zones and Clustering and
configuration neighbors peers

Microsoft DNS server

RFC 2782 [3]
RFC 2782 [3]
BIND 8 & 9
Call Bandwidth
processing control
196
CISCO TELEPRESENCE VIDEO COMMUNICATION SERVER
DNS and BIND
Firewall
Applications Maintenance
traversal
ADMINISTRATOR GUIDE
[6].
Appendices