Evaluate the deployment readiness for Azure Local rack aware cluster

This article describes how to use the Link Layer Discovery Protocol (LLDP) validator in a standalone mode to assess how ready your environment is for deploying rack aware cluster.

About the LLDP validator

The Link Layer Discovery Protocol (LLDP) validator collects and analyzes network topology information from your switches to document the physical network connections for Azure Local rack aware cluster deployments. The validator uses LLDP data advertised by your network switches to map the connectivity between nodes and switches.

The LLDP validator isn't included in the default deployment validation process. You can run the tool before deployment to verify your network configurations.

Prerequisites

• LLDP must be enabled on your network switches.
• Run the validator on the actual hardware intended for deployment.

Tests performed

The LLDP validator performs the following checks:

• LLDP neighbor discovery. Collects LLDP information from all network adapters and verifies switches are advertising their identity.

• Availability zone consistency (rack aware clusters). Documents the switches each rack connects to and validates the following:

  • All nodes within a rack connect to the same switches.
  • Different racks connect to separate switches with no overlap.

• Topology mapping. Creates detailed JSON files documenting the discovered network topology.

Run the LLDP validator

To run the validator before deployment, sign in to one cluster server and run the following PowerShell cmdlets:

# Define all server IPs for your Rack Aware Cluster
$allServers = @("<ServerIP1>", "<ServerIP2>", "<ServerIP3>", "<ServerIP4>")  # Replace with actual IPs
$userName = "<LOCALADMIN>"
$secPassWord = ConvertTo-SecureString "<LOCALADMINPASSWORD>" -AsPlainText -Force
$hostCred = New-Object System.Management.Automation.PSCredential($userName, $secPassWord)

# Create PowerShell sessions to all nodes
[System.Management.Automation.Runspaces.PSSession[]] $allServerSessions = @()
foreach ($currentServer in $allServers) {
    $currentSession = Microsoft.PowerShell.Core\New-PSSession -ComputerName $currentServer -Credential $hostCred -ErrorAction Stop
    $allServerSessions += $currentSession
}

# Create an alias for Trace-Execution
function TraceExecutionPreviewBypass { [CmdletBinding()] param( [Parameter(ValueFromRemainingArguments=$true)] $RemainingArgs ) }
Set-Alias -Name Trace-Execution -Value TraceExecutionPreviewBypass -Force -Scope Global

# Run the LLDP validator
$localAvailabilityZones = @(
    @{
        localAvailabilityZoneName = "Rack01"
        nodes = @("Node01", "Node02")
    },
    @{
        localAvailabilityZoneName = "Rack02"
 nodes = @("Node03", "Node04")
    }
)

$physicalNodes = @(
    @{
        Name = "Node01"
        IPv4Address = "10.x.x.x"
    },
    @{
        Name = "Node02"
        IPv4Address = "10.x.x.x"
    },
    @{
        Name = "Node03"
        IPv4Address = "10.x.x.x"
    },
    @{
        Name = "Node04"
        IPv4Address = "10.x.x.x"
    }
)

Invoke-AzStackHciLLDPValidation -PSSession $allServerSessions -PhysicalNodeList $physicalNodes -LocalAvailabilityZones $localAvailabilityZones -ClusterPattern 'RackAware'

Sample output

The following sample output shows results from a run of the LLDP validator. The result shows that the merged LLDP JSON file was successfully generated. It also shows validation checks that need attention, including Cross-Zone Switch Isolation, Host LLDP Neighbor Existence, and Intra-Zone Switch Consistency. Each item includes a description of the issue and the recommended remediation steps to resolve the issue.

Validator output

When you run the LLDP validator, it produces two types of output:

Log files

These files contain detailed LLDP discovery information. The default location for log files is $env:TEMP\LLDPValidation.

Generated JSON files

These files contain structured data that documents your network topology. The following table lists the generated JSON files with their descriptions:

Review topology files

After the LLDP validator completes, you can review the generated topology files to understand how nodes and switches are connected in your environment. You can run the following PowerShell cmdlets to review the generated JSON files:

# View node-to-switch mapping
Get-Content "C:\CloudDeployment\Logs\Node2Switch.json" | ConvertFrom-Json | Format-List

# View switch-to-node mapping  
Get-Content "C:\CloudDeployment\Logs\Switch2Node.json" | ConvertFrom-Json | Format-List

# View complete LLDP data
Get-Content "C:\CloudDeployment\Logs\MergedLLDPData.json" | ConvertFrom-Json

Sample JSON outputs

If the test result shows remediation steps, it indicates that the test failed. These remediation steps provide guidance to help you resolve the issue.

• Sample output of the AzStackHci_LLDP_Test_Intra_Zone_Switch_Consistency validation test:

  This test validates that all nodes within the same Availability Zone (rack) are connected to the same set of switches, as required by the rack aware cluster configuration.

  

• Sample output of the AzStackHci_LLDP_Test_Cross_Zone_Switch_Isolation validation test:

  This test validates cross-zone switch isolation in a rack aware cluster environment.

  

Next steps

• After validating your environment with the LLDP validator, proceed to deploy your Azure Local rack aware cluster by following the instructions in one of the following articles:
  • Deploy a rack aware cluster using Azure portal.
  • Deploy a rack aware cluster using Azure Resource Manager templates.

This feature is available in Azure Local 2510 and later.