TANDBERG Security Camera manual DNS Configuration

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DNS Configuration

TANDBERG VIDEO COMMUNICATIONS SERVER ADMINISTRATOR GUIDE

Overview Microsoft DNS Server

This section gives examples of DNS configuration using Microsoft DNS Server and BIND 8 & 9.

In these examples we 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.

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 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 RFC 2782 [3]
Weight	is the weight as defined by RFC 2782 [3]
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

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.

BIND 8 & 9

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 -toption, 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 DNS and BIND [6].

Introduction	Getting Started	Overview and	System	VCS	Zones and	Call	Bandwidth	Firewall	Maintenance	Appendices
		Status	Configuration	Configuration	Neighbors	Processing	Control	Traversal
D14049.03					185
MAY 2008