Sidewinder G2 6.1.2 Administration Guide - Glossary of Technical ...

Figure 140: Mail
exchanger example
Configuring the
internal network
to use hosted
DNS
Lloyd
(Request)
MX record
request for
foo.com
(Response)
e-mail message for
sharon@foo.com
Chapter 11: DNS (Domain Name System)
Configuring the internal network to use hosted DNS
name server for foo.com
MX record*
for foo.com
Sidewinder G2
fw.foo.com
* MX record for foo.com
fw.foo.com
A master name server stores and controls your site’s MX records. The master
name server may be in the external burb of your Sidewinder G2, or on a host
outside of your network (for example, your Internet service provider). If your
Sidewinder G2 controls the master name server, then you can make any
necessary changes to your MX records; if another host controls your master
name server, then changes have to be made on that host. For more
information on MX records see Chapter 5 of DNS and Bind by Albitz & Liu.
For information on creating MX records using the Admin Console, see “Using
the Master Zone Attributes tab” on page 329.
If you are going to use transparent proxies to provide Internet services to your
internal users, the internal client workstations must send their name server
queries to the Sidewinder G2 or to other internal name servers that forward
unresolved host names to the Sidewinder G2. There are two ways to set this
up:
• Reference the Sidewinder G2 in any name resolution configuration that the
client workstation may have. For example, a UNIX system uses the /etc/
resolv.conf file to list the name servers that system should query. A name
server reference for the Sidewinder G2 is all that is needed.
• Point client workstations at one or more internal name servers. These
name servers should be authoritative for the internal domain and
configured as slave forwarders, with the Sidewinder G2 as the forwarding
destination.
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