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IT 3100: Systems Design and Administration I

Domain Name System (DNS) Caching Lookup


In this assignment, you will configure the two existing name servers to be secure caching lookup servers in addition to their roles as authoritative servers.

Throughout the semester these servers must be functioning correctly. As systems are added, removed or changed in your domain, they should use these servers for DNS lookup.

You will also configure all of your existing systems to use these servers for caching lookup.

Configure the caching lookup servers

Configure each of the caching lookup servers the same way.

Only allow hosts within in your LAN (16 IPs) to ask for caching lookup. You may add a few other single IPs for testing purposes, but no other networks.

For BIONIC, you need to edit the following file: /etc/default/bind9. You should append a -4 to the options line, so it reads like this OPTIONS="-u bind -4"

Log all queries to the log file.

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

Change the /etc configuration files so that your systems use look for hosts in your domain automatically.


Verify that your systems correctly lookup translations when they should.

Verify that your systems correct deny lookup translations when they should.

Submission File Format

Create a report with the following elements:

The submission file is a UNIX text file, and must have this format, exactly! Since you now have 7 VMs, you must list them all in the hosts section of the file.

The file must be named dns_info.txt.

master:  ip_address_of_your_master
slave:   ip_address_of_your_slave
domain:  name.of.your.domain
ns1:     name.of.your.ns1
ns2:     name.of.your.ns2
hosts:,, and list all 7 hosts

For example, my file would look like this:

hosts:,,,, and list the other 3.


Last Updated 08/07/2020