Dns Overview; Static Domain Name Resolution; Dynamic Domain Name Resolution - 3Com MSR 50 Series Configuration Manual

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DNS Overview

Static Domain Name
Resolution
Dynamic Domain Name
Resolution
DNS C
When configuring DNS, go to these sections for information you are interested in:
"DNS Overview" on page 609
■
"Configuring the DNS Client" on page 611
■
"Configuring the DNS Proxy" on page 612
■
"Displaying and Maintaining DNS" on page 612
■
"DNS Configuration Examples" on page 613
■
"Troubleshooting DNS Configuration" on page 618
■
n
This document only covers IPv4 DNS configurations. For IPv6 DNS configuration
information, refer to
Domain name system (DNS) is a distributed database used by TCP/IP applications
to translate domain names into corresponding IP addresses. With DNS, you can
use easy-to-remember domain names in some applications and let the DNS server
translate them into correct IP addresses.
There are two types of DNS services,
609 and "Dynamic Domain Name Resolution" on page
server receives a name query it checks its static DNS database before looking up
the dynamic DNS database. Reduction of the searching time in the dynamic DNS
database would increase efficiency. Some frequently used addresses can be put in
the static DNS database.
The static domain name resolution means setting up mappings between domain
names and IP addresses. IP addresses of the corresponding domain names can be
found in the static DNS database when you use applications such as telnet.
Resolving procedure
Dynamic domain name resolution is implemented by querying the DNS server. The
resolution procedure is as follows:
1 A user program sends a name query to the resolver in the DNS client.
2 The DNS resolver looks up the local domain name cache for a match. If a match is
found, it sends the corresponding IP address back. If not, it sends a query to the
DNS server.
3 The DNS server looks up the corresponding IP address of the domain name in its
DNS database. If no match is found, it sends a query to a higher DNS server. This
process continues until a result, whether success or failure, is returned.
ONFIGURATION
"IPv6 Basics Configuration" on page
"Static Domain Name Resolution" on page
655.
609. Each time the DNS