Cisco WS-C4003 Software Guide - Page 471
Configuring DNS, Understanding How DNS Works, DNS Default Configuration
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Configuring DNS 34 C H A P T E R This chapter describes how to configure the Domain Name System (DNS) on the Catalyst enterprise LAN switches. Note For complete syntax and usage information for the commands used in this chapter, refer to the Command Reference-Catalyst 4000 Family, Catalyst 2948G, and Catalyst 2980G Switches. This chapter consists of these sections: • Understanding How DNS Works, page 34-1 • DNS Default Configuration, page 34-1 • Configuring DNS, page 34-2 Understanding How DNS Works DNS is a distributed database with which you can map host names to IP addresses through the DNS protocol from a DNS server. When you configure DNS on the switch, you can substitute the host name for the IP address with all IP commands, such as ping, telnet, upload, and download. To use DNS, you must have a DNS name server on your network. You can specify a primary DNS name server on the switch as well as two backup servers. The first server specified is the primary unless you explicitly identify the primary server. The switch sends DNS queries to the primary server first. If the query to the primary server fails, the backup servers are queried. DNS Default Configuration Table 34-1 shows the default DNS configuration. Table 34-1 DNS Default Configuration Feature DNS enable state DNS default domain name DNS servers Default Value Disabled Null None specified 78-12647-02 Software Configuration Guide-Catalyst 4000 Family, Catalyst 2948G, Catalyst 2980G, Releases 6.3 and 6.4 34-1
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