Assignment 2: DNS service

DNS server

DNS server (authoritative and forward mode): You should deploy a local name resolution service (DNS) on server-01 using the bind9 software. You will have to configure it as a “primary” and authoritative DNS for the localdomain zone and to use a “cache” operation mode.

1. Installation: (1)

   • bind9

2. Configuration:

   • Figure out the system unit (target) for bind9 service.

   • Bind9 daemon must be run under “no root” user privileges: bind regular user

   • Bind9 must be configured as a forward DNS service, so you can use the next IP as external DNS (forwarders), if necessary:

     • 169.254.169.254 (2)

   • Ensure that any computer in the INTRANET is allowed to query the DNS server and enable recursion, which will allow your local DNS server to query other DNS servers.

   • Also, configure it as a “local primary” authoritative DNS server to carry out the direct and reverse name resolution for localdomain domain. So, you should add the DNS information about local hosts (server-01, server-02 and frontend, for the moment). Include one network alias forserver-01, called “sso” (3)

More details in references [2][3][4]

DNS client

frontend should manage the name resolution using server-01, as the main DNS server. Keep IP 169.254.169.254 (metadata server in GCP) as its secondary DNS.

1. Configure the frontend host according to it.

2. Check from frontend that the DNS service running on server-01 is ok. You can use bind9-dnsutils, for example:

   • $ nslookup server-01

   • $ nslookupwww.unican.es (or www.google.es …)

   • $ nslookup 10.128.0.11

(1) Use the official debian software repositories.

(2) We will use the metadata server of Google (GCP).

(3) Single Sign-On.