Domain Name System (DNS)

Assignment: 
Install and configure domain name server software, manage a DNS domain.

Requirements: 

• Register a domain name with the proper authorities.
• Configure primary and secondary authoritative domain name servers for a domain.
• Configure primary and secondary authoritative domain name servers for a reverse lookup zone.
• Configure two caching lookup domain name servers.
• Correct the hostname, domain, and DNS lookup of all systems.
• Write a shell script to verify that DNS is working correctly.

Register a domain name with the proper authorities: 

• Decide on a domain name, check that it is not used. Repeat until a unique domain name has been found.
• Register your domain name with a registrar. Many can be found on the net. See the links below. You should not pay more than $10 for this service. Be sure to accurately fill out the contact information. You must put "Curtis Larsen, 225 South 700 East, St. George UT cgl at dixie.edu" as the technical contact.

Configure primary and secondary authoritative domain name servers for a domain: 

• On one system configure the files in /etc/bind/ to become the primary authoritative server for your domain.
• On another system configure the files in /etc/bind/ to become the secondary authoritative server for your domain.
• Verify that your domain name servers are working correctly.
• Return to your registrar's configuration site and assign your systems as the primary and secondary name servers (Note that you must first register the systems as a name servers, then assign your domain to be served by the name servers.)
• Verify that the rest of the domain name system is correctly finding your name server. (This may take up to 48 hours.)

Domain Configuration Details: 

• Allow hosts from any IP address to lookup information about your domain.
• Allow your backup name servers to transfer the entire zone.
• Automatically notify your backup servers of changes to your zone.
• Configure names for at least 8 of the IP addresses in your control.
• Configure aliases so that www, ftp, sql, and mail point to hosts in your domain.
• It is conventional to configure your name servers with the names ns1 and ns2.

Configure primary and secondary authoritative domain name servers for a reverse lookup zone: 

• On one system configure the files in /etc/bind/ to become the primary authoritative for the reverse lookup of IPs in your control. (This is the set of 16 IPs sent to you in your registration packet.)
• On another system configure the files in /etc/bind/ to become the secondary authoritative for the reverse lookup of IPs in your control. (This is the set of 16 IPs sent to you in your registration packet.)
• Your reverse zone is aaa-bbb.ccc.38.144.in-addr.arpa., where aaa is the first number in your control, and bbb is the last number in your control. ccc is 210, 211, or 212 depending on your assigned numbers. For example, my zone is 48-63.212.38.144.in-addr.arpa..
• Verify that your domain name servers are working correctly.
• Submit the full DNS names of your name servers to the reverse zone registrar. That is the course instructor. Send the information via email to it3100 at cs.dixie.edu.
• Verify that the rest of the domain name system is correctly finding your name server for reverse lookup.

Domain Reverse Details: 

• Allow hosts from any IP address to lookup information about your reverse domain.
• Allow your backup name servers to transfer the entire zone.
• Automatically notify your backup servers of changes to your zone.
• Configure reverse lookup information for each of the IPs used in your forward lookup zone. These names should match the A records from the forward zone.

Configure two caching lookup domain name servers: 

• Both of your DNS servers will be used as caching lookup servers.
• Only allow hosts from 144.38.192.0/19 to ask for DNS lookups.
• Limit the cache size to 1 MByte.

Correct the hostname, domain, and DNS lookup of all systems: 

• Change the /etc configuration files so that the operating system knows the correct host and domain names for your systems.
• Change the /etc configuration files so that your systems use your DNS lookup servers first and second. As a third backup they may use 144.38.192.2.
• Change the /etc configuration files so that your systems use look for hosts in your domain automatically.
• Verify that your configuration changes are working correctly.

Write a shell script to verify that DNS is working correctly: 

• Write a shell script to verify each of the functions of your DNS servers.
• The script file shall be named check_dns.bash.
• This script should be flexible. This means driven by command line parameters, configuration files, or configuration variables at the top of the file.

Pass-off Procedure: 

• Use the CIT submission system.
• Submit check_dns.bash.
• Submit a text file named dns_info.txt. This file must be a plain text file, with the following format:

  master: ip_address_of_master
  
  slave: ip_address_of_slave
  
  domain: name.of.domain
  

  For example, my file would look like this:

  master: 144.38.212.48
  
  slave: 144.38.212.49
  
  domain: horgoth.com
  

Links and Help: 

• Sample registrars:
  US Business Link
  Go Daddy
• InterNic
• Testing: man dig
• http://www.dnsreport.com/
• Debugging: less /var/log/daemon.log
• Configuration Files: /etc/bind