Patton electronics SmartWare R.3.20 Software Configuration Manual page 258

SmartWare Software Configuration Guide
address. DNS Relay agents maintain a cache of host names and IP addresses, much smaller than a DNS Server.
It acts as a liaison between the DNS Server and the DNS client
Advantages in configuring a DNS Relay in the SmartNode are:
• Network traffic is reduced since only a single query is sent to the DNS server although numerous users may
be requesting an IP address for the same host name
• The DNS queries are localized between the Users and the SmartNode which reduces congestion on the
WAN side of the SmartNode
• Multiple DNS servers can be consulted from the SmartNode
The DNS resolver must be configured before you can use the DNS relay feature (see section
DNS resolver" on page 256 to enable the DNS resolver, if you have not already done so).
Do the following to enable the DNS relay feature:
Mode: Configure
Step Command
node (cfg)#dns-relay
1
Example: Enabling DNS relay
The following example shows how to enable the DNS relay feature.
node>enable
node#configure
node(cfg)#dns-relay
Note If a DHCP server profile has been set up, you can announce the SmartNode
as domain name server to the DHCP clients as follows:
node(cfg)#profile dhcp-server LAN
node(pf-dhcps)[LAN]#domain-name-server <ip-address>
Where ip-address must be the IP address of the SmartNode IP interface to
which the DHCP clients are connected.
DNS configuration task list
Enables DNS relay feature
22 • DNS configuration
"Enabling the
Purpose
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