2 -------------------------------------------
4 The Domain Name System (DNS) is a hierarchical naming system for computers,
5 services, or any resource participating in the Internet. It associates various
6 information with domain names assigned to each of the participants. Most
7 importantly, it translates domain names meaningful to humans into the numerical
8 (binary) identifiers associated with networking equipment for the purpose of
9 locating and addressing these devices world-wide. An often used analogy to
10 explain the Domain Name System is that it serves as the "phone book" for the
11 Internet by translating human-friendly computer hostnames into IP addresses.
12 For example, www.example.com translates to 208.77.188.166.
14 For more information on DNS - http://en.wikipedia.org/wiki/Domain_Name_System
19 ------------------------------------------
21 CONFIG_CMD_DNS - controls if the 'dns' command is compiled in. If it is, it
22 will send name lookups to the dns server (env var 'dnsip')
23 Turning this option on will about abou 1k to U-Boot's size.
30 bfin> dns www.google.com
33 By default, dns does nothing except print the IP number on
34 the default console - which by itself, would be pretty
35 useless. Adding a third argument to the dns command will
36 use that as the environment variable to be set.
41 ## Error: "googleip" not defined
42 bfin> dns www.google.com googleip
45 googleip=64.233.161.104
46 bfin> ping ${googleip}
47 Using Blackfin EMAC device
48 host 64.233.161.104 is alive
50 In this way, you can lookup, and set many more meaningful
55 bfin> dns pool.ntp.org ntpserverip
58 Date: 2009-07-18 Time: 4:06:57
60 For some helpful things that can be related to DNS in U-Boot,
61 look at the top level README for these config options: