This lab demonstrates the behavior of DNS records in a domain environment, including A records, DNS caching, and the use of CNAME records. Testing was done using Azure-hosted virtual machines configured as a domain controller (DC-1) and a domain-joined client (Client-1).
- Microsoft Azure (VM deployment)
- Windows Server (Domain Controller)
- Active Directory DNS
- DNS Records (A-Record, CNAME)
- DNS Client Tools (nslookup, ipconfig)
- DNS Cache Management
Logged into:
- DC-1 as
mydomain.com\jane_admin - Client-1 as
mydomain\jane_admin
On Client-1:
- Attempted to ping
mainframe→ Request failed - Ran
nslookup mainframe→ No DNS record found
On DC-1:
- Created a DNS A Record for
mainframe - Pointed the A record to DC-1's Private IP Address
Back on Client-1:
- Pinging
mainframenow succeeded, confirming that the DNS record propagated correctly
On DC-1:
- Modified the existing A record for
mainframe, changing the IP address to8.8.8.8
Back on Client-1:
- Pinged
mainframeagain → Still resolved to the old IP address - Ran
ipconfig /displaydns→ Confirmed the outdated address was cached locally
To refresh:
- Executed
ipconfig /flushdnsto clear the local DNS cache - Verified cache clearance with
ipconfig /displaydns - Pinged
mainframeagain → Now resolved to the updated address (8.8.8.8)
On DC-1:
- Created a CNAME Record: aliased
searchtowww.google.com
On Client-1:
- Pinging
searchresolved to Google's public address, showing successful aliasing - Ran
nslookup search→ Confirmed that the CNAME record correctly redirected towww.google.com
This lab provides foundational hands-on experience in Active Directory-integrated DNS management, a critical skill for system and network administrators. Key competencies developed include:
- Creating and troubleshooting A Records for internal name resolution
- Observing and managing DNS client-side caching behavior
- Configuring CNAME (alias) records for flexible DNS mappings
- Using tools like
ping,nslookup, andipconfigto validate DNS functionality and diagnose issues - Understanding the propagation and caching process of DNS records in enterprise environments
These skills are essential for managing scalable, secure networks and play a key role in IT operations, cybersecurity, and cloud administration.
All screenshots for this lab can be found in the screenshots folder.