Overview

This guide covers the complete process for updating DNS records when a customer requests to change a subdomain's IP address. It ensures both internal and external users can access the subdomain with the new IP.

When to Use This Guide

  • Customer requests IP address change for a subdomain (e.g., subdomain.cyp.org.au)
  • New server deployment requiring DNS updates
  • IP address migration projects
  • Any request to "update DNS to point to new IP"

Understanding DNS Requirements

Two types of DNS records may need updating:

  • Internal DNS (Windows Server): For users within your network
  • External DNS (Internet providers): For users accessing from the internet

Important: Most subdomains require BOTH internal and external DNS updates to work properly.

Step 1: Determine What Needs Updating

Check if the subdomain exists internally:

# Check your internal DNS (replace with your DNS server IP) Resolve-DnsName -Name "subdomain.cyp.org.au" -Server 192.168.212.10 -Type A

Check if the subdomain exists externally:

# Check external DNS (what internet users see) Resolve-DnsName -Name "subdomain.cyp.org.au" -Server 8.8.8.8 -Type A

Decision Matrix:

  • Both return results → Update both internal AND external DNS
  • Only internal returns results → Update internal DNS only
  • Only external returns results → Update external DNS only
  • Neither returns results → Create new records (both internal and external)

Step 2: Find Your DNS Server Information

Find your internal DNS server IP:

# Shows your internal DNS servers ipconfig /all

Look for the "DNS Servers" line. Typically shows something like 192.168.212.10.

Find your external DNS provider:

# Check who manages external DNS nslookup -type=NS cyp.org.au 8.8.8.8

Example result:

cyp.org.au      nameserver = ns1.partnerconsole.net cyp.org.au      nameserver = ns2.partnerconsole.net

This shows partnerconsole.net manages your external DNS.

Step 3: Update Internal DNS (if required)

Access DNS Manager:

  • Method 1: Start → Administrative Tools → DNS
  • Method 2: Run dnsmgmt.msc from Start → Run
  • Method 3: Server Manager → Tools → DNS

Navigate to your domain:

  1. Expand your DNS server name
  2. Expand "Forward Lookup Zones"
  3. Click on "cyp.org.au"

Update the DNS record:

Option A - Edit existing record:

  1. Right-click on the existing A record
  2. Select "Properties"
  3. Change IP address to the new one
  4. Click "OK"

Option B - Create new record:

  1. Right-click in the zone area → "New Host (A or AAAA)..."
  2. Enter subdomain name (e.g., "databasetest")
  3. Enter new IP address (e.g., "172.105.165.163")
  4. Click "Add Host" → "Done"

Verify internal DNS change:

# Test the internal DNS change Resolve-DnsName -Name "subdomain.cyp.org.au" -Server 192.168.212.10 -Type A

Step 4: Update External DNS (if required)

Access your external DNS provider:

  1. For Zoik Partner Console: Go to https://zoik.partnerconsole.net/
  2. For other providers: Check your domain registrar or DNS service
  3. Find login credentials in your organization's password manager

Update the external DNS record:

  1. Log into the DNS management portal
  2. Navigate to DNS management or Domain management
  3. Find your domain (cyp.org.au)
  4. Locate or create the subdomain A record
  5. Update the IP address to the new one
  6. Save changes

Note: External DNS changes can take 5 minutes to 24 hours to propagate globally.

Step 5: Verify All Changes

Test internal DNS:

# Verify internal users will see the correct IP Resolve-DnsName -Name "subdomain.cyp.org.au" -Server 192.168.212.10 -Type A

Test external DNS:

# Verify external users will see the correct IP Resolve-DnsName -Name "subdomain.cyp.org.au" -Server 8.8.8.8 -Type A

Test multiple external DNS servers:

# Check propagation across multiple external DNS providers $externalDNS = @("8.8.8.8", "1.1.1.1", "208.67.222.222", "9.9.9.9") 
foreach ($server in $externalDNS) {    Write-Host "External DNS $server shows:" -ForegroundColor Yellow    try {        $result = Resolve-DnsName -Name "subdomain.cyp.org.au" -Server $server -Type A -ErrorAction Stop        Write-Host "  $($result.IPAddress)" -ForegroundColor Green    }    catch {        Write-Host "  No record found" -ForegroundColor Red    } }

Success criteria:

  • Internal DNS shows new IP address
  • External DNS shows new IP address (may take time to propagate)

Step 6: Customer Communication

Initial Response Template:

Hi [Customer Name], 
I've received your request to update [subdomain.cyp.org.au] to point to [new IP address]. 
I'll update both our internal DNS server and external DNS provider to ensure the change works for all users. This process typically takes a few minutes for internal users and up to 24 hours for external propagation. 
I'll confirm once the updates are complete. 
Thanks!

Completion Response Template:

Hi [Customer Name], 
I've successfully updated the DNS records for [subdomain.cyp.org.au] to point to [new IP address]. 
Updates completed: ✅ Internal DNS server - Active immediately for internal users ✅ External DNS provider - Propagating globally (up to 24 hours) 
Current status: - Internal network: [subdomain] now resolves to [new IP] - External/Internet: Change is propagating, should be fully active within 24 hours 
Please test the connection and let me know if you encounter any issues after 24 hours. 
Thanks!

Common Scenarios

Scenario 1: Internal-only subdomain

  • Example: intranet.cyp.org.au for internal company use
  • Action: Update internal DNS only
  • Verification: Test with internal DNS server only

Scenario 2: External-only subdomain

  • Example: api.cyp.org.au hosted in cloud
  • Action: Update external DNS only
  • Verification: Test with external DNS servers only

Scenario 3: Public-facing subdomain

  • Example: databasetest.cyp.org.au accessible from anywhere
  • Action: Update both internal AND external DNS
  • Verification: Test both internal and external DNS servers

Pre-Update Checklist

Before making any DNS changes:

  • [ ] Confirm the exact subdomain name
  • [ ] Verify the new IP address is correct
  • [ ] Test if the subdomain currently exists (internal/external)
  • [ ] Identify which DNS systems need updating
  • [ ] Have access credentials for external DNS provider
  • [ ] Set customer expectations for propagation time

Post-Update Checklist

After making DNS changes:

  • [ ] Verify internal DNS shows new IP (if updated)
  • [ ] Verify external DNS shows new IP (if updated)
  • [ ] Test from both internal and external perspectives
  • [ ] Document which systems were updated
  • [ ] Send completion notification to customer
  • [ ] Set follow-up reminder for 24 hours (if external DNS changed)

Important Reminders

  • Always check both internal and external DNS before starting
  • Update all relevant DNS systems - don't assume one covers everything
  • External DNS changes are not instant - allow up to 24 hours
  • Test your changes before notifying the customer
  • Keep external DNS login credentials secure and accessible
  • Document the change for future reference

Emergency Rollback

If you need to revert changes:

  1. Internal DNS: Use DNS Manager to change IP back to original
  2. External DNS: Log into provider and change IP back to original
  3. Verify rollback: Test both internal and external resolution
  4. Notify customer: Explain the rollback and next steps

Remember: External DNS rollbacks also take time to propagate!