55 dns configuration, Dns overview, Static domain name resolution – H3C Technologies H3C WX6000 Series Access Controllers User Manual
Page 511: Dynamic domain name resolution, Resolving procedure, Dns configuration
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DNS Configuration
When configuring DNS, go to these sections for information you are interested in:
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Displaying and Maintaining DNS
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Troubleshooting DNS Configuration
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The term switch in this document refers to a switch in a generic sense or an access controller
configured with the switching function unless otherwise specified.
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This document only covers IPv4 DNS configurations. For introduction to IPv6 DNS configurations,
refer to IPv6 in H3C WX6103 Access Controller Switch Interface Board Configuration Guide.
DNS Overview
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, static and dynamic. After a user specifies a name, the device
checks the local static name resolution table for an IP address. If no IP address is available, it contacts
the DNS server for dynamic name resolution, which takes more time than static name resolution.
Therefore, some frequently queried name-to-IP address mappings are stored in the local static name
resolution table to improve efficiency.
Static Domain Name Resolution
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 domain
resolution table when you use applications such as telnet.
Dynamic Domain Name Resolution
Resolving procedure
Dynamic domain name resolution is implemented by querying the DNS server. The resolution
procedure is as follows: