Operation Manual – DNSH3C S7500E Series Ethernet Switches Chapter 1 DNS Configuration1-1Chapter 1 DNS ConfigurationWhen configuring DNS, go to these sections for information you are interested in:z DNS Overviewz Configuring the DNS Clientz Configuring the DNS Proxyz Displaying and Maintaining DNSz DNS Configuration Examplesz Troubleshooting DNS ConfigurationNote:This document only covers IPv4 DNS configurations. For introduction to IPv6 DNSconfigurations, refer to IPv6 Configuration.1.1 DNS OverviewDomain Name System (DNS) is a distributed database used by TCP/IP applications totranslate domain names into corresponding IP addresses. With DNS, you can useeasy-to-remember domain names in some applications and let the DNS servertranslate 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 IPaddress is available, it contacts the DNS server for dynamic name resolution, whichtakes more time than static name resolution. Therefore, some frequently queriedname-to-IP address mappings are stored in the local static name resolution table toimprove efficiency.1.1.1 Static Domain Name ResolutionThe static domain name resolution means setting up mappings between domainnames and IP addresses. IP addresses of the corresponding domain names can befound in the static domain resolution table when you use applications such as telnet.
