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PETER Samuel
PETER Samuel

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Mastering Azure VNet Peering: How I Connected Isolated Cloud Networks Like a Pro

The "Aha!" Moment That Changed Everything

I'll never forget the moment I ran Test-NetConnection after setting up VNet peering and saw TcpTestSucceeded: True - after hours of failed connections, everything finally worked! Here's my real journey through Azure networking, complete with screenshots of every step.

Step 1: Setting Up My Test Environment (The Manual Way)
Why I Ditched the Templates:
The lab provided ARM templates, but I chose manual creation to really understand what was happening behind the scenes.

What I Actually Did:

Created TestVM in ManufacturingVnet:

Resource Group: ContosoResourceGroup

Location: UK West (to match my VNet)

Virtual Network: ManufacturingVnet

Subnet: default (10.30.0.0/24)

Verified TestVM1 in CoreServicesVnet:

Already existed from previous lab

Step 2: The RDP Struggle & Finding Better Solutions

The Problem Every Azure Admin Faces:
RDP connections failed repeatedly with that frustrating "can't connect" message.

My Workaround That Actually Worked Better:
Discovered Azure Run Command:

TestVM → Operations → Run command → RunPowerShellScript

Used Serial Console as Backup:

Perfect for when RDP fails

Direct command-line access

Step 3: The Baseline Test - Proving Isolation

Getting TestVM1's IP:
powershell
ipconfig

The Expected Failure:
powershell
Test-NetConnection 10.20.20.4 -port 3389

This proved the networks were completely isolated - which was exactly what we expected at this stage.

Step 4: Building the Network Bridge - VNet Peering
The Magic Configuration:

CoreServicesVnet → Peerings → + Add:

Peering link name: ManufacturingVnet-to-CoreServicesVnet

Virtual network: ManufacturingVnet

Allow access: Enabled

Automatic Reverse Peering Created:

CoreServicesVnet-to-ManufacturingVnet

Clicked "Sync" and Watched the Status Change:

From "Initiated" to "Connected"

Step 5: The Moment of Truth - Testing Connectivity
Running the Exact Same Command:
powershell
Test-NetConnection 10.20.20.4 -port 3389
The Beautiful Result:
text
TcpTestSucceeded: True
ComputerName: 10.20.20.4
RemotePort: 3389

Step 6: Cleanup & Cost Management

Removing Resources Properly:
powershell
Remove-AzResourceGroup -Name 'ContosoResourceGroup' -Force -AsJob

Key Lessons That Made Me a Better Cloud Engineer

Technical Insights:

Manual configuration > templates for learning

Run Command is incredibly powerful for administration

Peering must be bidirectional to work properly

Business Value Realized:
Cost savings by eliminating VPN gateways

Performance boost through Azure backbone

Security enhancement with private connectivity

Why This Matters for Your Organization
If you're managing multiple Azure environments, VNet peering isn't just technical - it's business-critical for:

Application integration between different teams

Hybrid cloud strategies

Compliance and security requirements

Ready to Help Others Succeed
I'm passionate about making cloud networking accessible. If your organization is facing similar challenges, I'd love to:

Share more detailed configurations

Help troubleshoot specific scenarios

Collaborate on Azure networking projects

What networking challenges are you facing? Share your experiences below!

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