SdnDiagnostics

3.2305.678.144935

modules/SdnDiag.Health/SdnDiag.Health.psm1

# Copyright (c) Microsoft Corporation.
# Licensed under the MIT License.

Using module .\..\SdnDiag.Common\SdnDiag.Common.Helper.psm1
Using module .\SdnDiag.Health.Helper.psm1

Import-Module $PSScriptRoot\SdnDiag.Health.Helper.psm1
Import-Module $PSScriptRoot\..\SdnDiag.Common\SdnDiag.Common.psm1
Import-Module $PSScriptRoot\..\SdnDiag.Utilities\SdnDiag.Utilities.psm1

# create local variable to store configuration data
New-Variable -Name 'SdnDiagnostics_Health' -Scope 'Script' -Force -Value @{
    Cache = @{}
}


##### FUNCTIONS AUTO-POPULATED BELOW THIS LINE DURING BUILD #####
function Test-EncapOverhead {
    <#
    .SYNOPSIS
        Retrieves the VMSwitch across servers in the dataplane to confirm that the network interfaces support EncapOverhead or JumboPackets
        and that the settings are configured as expected
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    [int]$encapOverheadExpectedValue = 160
    [int]$jumboPacketExpectedValue = 1674 # this is default 1514 MTU + 160 encap overhead
    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validating the network interfaces across the SDN dataplane support Encap Overhead or Jumbo Packets" | Trace-Output

        $encapOverheadResults = Invoke-PSRemoteCommand -ComputerName $SdnEnvironmentObject.ComputerName -Credential $Credential -Scriptblock {Get-SdnNetAdapterEncapOverheadConfig}
        if($null -eq $encapOverheadResults){
            $sdnHealthObject.Result = 'FAIL'
        }
        else {
            foreach($object in ($encapOverheadResults | Group-Object -Property PSComputerName)){
                foreach($interface in $object.Group){
                    "[{0}] {1}" -f $object.Name, ($interface | Out-String -Width 4096) | Trace-Output -Level:Verbose

                    if($interface.EncapOverheadEnabled -eq $false -or $interface.EncapOverheadValue -lt $encapOverheadExpectedValue){
                        "EncapOverhead settings for {0} on {1} are disabled or not configured correctly" -f $interface.NetworkInterface, $object.Name | Trace-Output -Level:Verbose
                        $encapDisabled = $true
                    }

                    if($interface.JumboPacketEnabled -eq $false -or $interface.JumboPacketValue -lt $jumboPacketExpectedValue){
                        "JumboPacket settings for {0} on {1} are disabled or not configured correctly" -f $interface.NetworkInterface, $object.Name | Trace-Output -Level:Verbose
                        $jumboPacketDisabled = $true
                    }

                    # if both encapoverhead and jumbo packets are not set, this is indication the physical network cannot support VXLAN encapsulation
                    # and as such, environment would experience intermittent packet loss
                    if ($encapDisabled -and $jumboPacketDisabled) {
                        $sdnHealthObject.Result = 'FAIL'
                        "EncapOverhead and JumboPacket for interface {0} on {1} are disabled or not configured correctly." -f $interface.NetworkInterface, $object.Name  | Trace-Output -Level:Exception
                    }

                    $array += $interface
                }
            }

            $sdnHealthObject.Properties = $array
        }

        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-HostRootStoreNonRootCert {
    <#
    .SYNOPSIS
        Validate the Cert in Host's Root CA Store to detect if any Non Root Cert exist
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validating Certificates under Root CA Store" | Trace-Output

        $scriptBlock = {
            $nonRootCerts = @()
            $rootCerts = Get-ChildItem Cert:LocalMachine\Root
            foreach ($rootCert in $rootCerts) {
                if ($rootCert.Subject -ne $rootCert.Issuer) {
                    $certInfo = [PSCustomObject]@{
                        Thumbprint = $rootCert.Thumbprint
                        Subject    = $rootCert.Subject
                        Issuer     = $rootCert.Issuer
                    }

                    $nonRootCerts += $certInfo
                }
            }
            return $nonRootCerts
        }

        foreach($node in $SdnEnvironmentObject.ComputerName){
            $nonRootCerts = Invoke-PSRemoteCommand -ComputerName $node -Credential $Credential -ScriptBlock $scriptBlock -PassThru
            # If any node have Non Root Certs in Trusted Root Store. Issue detected.
            if($nonRootCerts.Count -gt 0){
                $sdnHealthObject.Result = 'FAIL'

                $object = [PSCustomObject]@{
                    ComputerName = $node
                    NonRootCerts = $nonRootCerts
                }

                $array += $object
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-NetworkControllerCertCredential {
    <#
    .SYNOPSIS
        Query the NC Cert credential used to connect to SDN Servers, ensure cert exist.
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [System.String[]]$NetworkController,

        [Parameter(Mandatory = $true)]
        [Uri]$NcUri,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $NcRestCredential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $arrayList = [System.Collections.ArrayList]::new()

    try {
        "Validate Cert Credential resource of SDN Servers. Ensure Cert exist on each of the Network Controller " | Trace-Output

        # enumerate each server's conection->credential object into the array
        $servers = Get-SdnServer -NcUri $NcUri.AbsoluteUri -Credential $NcRestCredential
        $serverCredentialRefs = [System.Collections.Hashtable]::new()
        foreach ($server in $servers) {
            # find the first connection with credential type of X509Certificate
            $serverConnection = $server.properties.connections | Where-Object { $_.credentialType -eq "X509Certificate" } | Select-Object -First 1;
            if ($null -ne $serverConnection) {
                $credRef = $serverConnection.credential[0].resourceRef
                "Adding credential {0} for server {1} for validation" -f $credRef, $serverConnection.managementAddresses[0] | Trace-Output -Level:Verbose
                if ($null -ne $credRef) {
                    if (-NOT $serverCredentialRefs.ContainsKey($credRef)) {
                        $serverList = [System.Collections.ArrayList]::new()
                        $serverCredentialRefs.Add($credRef, $serverList)
                    }

                    [void]$serverCredentialRefs[$credRef].Add($server)
                }
            }
        }

        # iterate the credential object to validate certificate on each NC
        foreach ($credRef in $serverCredentialRefs.Keys) {
            $credObj = Get-SdnResource -NcUri $NcUri.AbsoluteUri -Credential $NcRestCredential -ResourceRef $credRef
            if ($null -ne $credObj) {
                $thumbPrint = $credObj.properties.value
                $scriptBlock = {
                    param([Parameter(Position = 0)][String]$param1)

                    if (-NOT (Test-Path -Path Cert:\LocalMachine\My\$param1)) {
                        return $false
                    }
                    else {
                        return $true
                    }
                }

                # invoke command on each NC seperately so to record which NC missing certificate
                foreach ($nc in $NetworkController) {
                    "Validating certificate [{0}] on NC {1}" -f $thumbPrint, $nc | Trace-Output -Level:Verbose
                    $result = Invoke-PSRemoteCommand -ComputerName $nc -Credential $Credential -ScriptBlock $scriptBlock -ArgumentList $thumbPrint
                    if ($result -ne $true) {
                        # if any NC missing certificate, it indicate issue detected
                        $sdnHealthObject.Result = 'FAIL'
                        $object = [PSCustomObject]@{
                            NetworkController  = $nc
                            CertificateMissing = $thumbPrint
                            AffectedServers    = $serverCredentialRefs[$credRef]
                        }

                        [void]$arrayList.Add($object)
                    }
                }

            }
        }

        $sdnHealthObject.Properties = $arrayList
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-NetworkInterfaceAPIDuplicateMacAddress {
    <#
    .SYNOPSIS
        Validate there are no adapters within the Network Controller Network Interfaces API that are duplicate.
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $NcRestCredential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validate no duplicate MAC addresses for network interfaces in Network Controller" | Trace-Output

        $networkInterfaces = Get-SdnResource -NcUri $SdnEnvironmentObject.NcUrl.AbsoluteUri -Resource:NetworkInterfaces -Credential $NcRestCredential
        if($null -eq $networkInterfaces){
            throw New-Object System.NullReferenceException("No network interfaces returned from Network Controller")
        }

        $duplicateObjects = $networkInterfaces.properties | Group-Object -Property privateMacAddress | Where-Object {$_.Count -ge 2}
        if($duplicateObjects){
            $sdnHealthObject.Result = 'FAIL'

            # since there can be multiple grouped objects, we need to enumerate each duplicate group
            foreach($obj in $duplicateObjects){
                $duplicateInterfaces = $networkInterfaces | Where-Object {$_.properties.privateMacAddress -eq $obj.Name}
                $array += $duplicateInterfaces

                "Located {0} virtual machines associated with MAC address {1}:`r`n`n{2}`r`n" -f $obj.Count, $obj.Name, `
                    ($duplicateInterfaces `
                    | Select-Object @{n="ResourceRef";e={"`t$($_.resourceRef)"}} `
                    | Select-Object -ExpandProperty ResourceRef `
                    | Out-String `
                ) | Trace-Output -Level:Warning
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-SdnKINetworkInterfacePlacement {
    <#
    .SYNOPSIS
        Validates the placement of Network Controller Network Interface API placement compared to Hypervisor.
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [Uri]$NcUri,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $NcRestCredential = [System.Management.Automation.PSCredential]::Empty
    )

    function Test-NetworkInterfaceLocation {
        param (
            [Parameter(Mandatory = $true)]
            [System.Object]$NetworkControllerNetworkInterfaces,

            [Parameter(Mandatory = $true)]
            [System.Object]$VMNetworkAdapters
        )
        $networkInterfaces = [System.Collections.ArrayList]::new()

        foreach ($netAdapter in $VMNetworkAdapters) {
            $netInterface = $NetworkControllerNetworkInterfaces | Where-Object {$_.properties.privateMacAddress -eq $netAdapter.MacAddress}

            # if we do not find the MAC address within NC Network Interfaces, skip the placement validation
            if ($null -eq $netInterface) {
                continue
            }

            # if we detect duplicate MAC addresses within the NC Network Interfaces API, skip placement validation
            if ($netInterface.resourceRef.Count -ge 2){
                continue
            }

            # locate the server resource reference for the network interface
            # in some instances, this may be null/empty, so need to handle those instances to prevent script failures
            if($netInterface.properties.server.resourceRef){
                [string]$server = $netInterface.properties.server.resourceRef.Replace('/servers/','')
            }
            else {
                [string]$server = 'NullServerReference'
            }

            if($netAdapter.ComputerName -ne $server){
                $result = [PSCustomObject]@{
                    nc_host = $server
                    hyperv_host = $netAdapter.ComputerName
                    vmName = $netAdapter.VmName
                    macAddress = $netAdapter.MacAddress
                    resourceMetadata = $netInterface.resourceMetadata
                }

                [void]$networkInterfaces.Add($result)
            }
        }

        return $networkInterfaces
    }

    try {
        "Validate placement of network interfaces between Network Controller and Hypervisor" | Trace-Output

        $issueDetected = $false
        $arrayList = [System.Collections.ArrayList]::new()

        $servers = Get-SdnServer -NcUri $NcUri.AbsoluteUri -ManagementAddressOnly -Credential $NcRestCredential
        $networkInterfaces = Get-SdnResource -NcUri $ncUri.AbsoluteUri -Resource:NetworkInterfaces -Credential $NcRestCredential
        $networkAdapters = Get-SdnVMNetworkAdapter -ComputerName $servers -Credential $Credential -AsJob -Timeout 600 -PassThru
        $driftedNetworkInterfaces = Test-NetworkInterfaceLocation -NetworkControllerNetworkInterfaces $networkInterfaces -VMNetworkAdapters $networkAdapters
        if ($driftedNetworkInterfaces) {
            # we want to focus on instances where network controller api does not have a valid server reference to where the mac address resides
            # this may be false positve if the VM had live migrated recently and nchostagent has not updated network controller
            if ($driftedNetworkInterfaces.nc_host -icontains 'NullServerReference') {
                foreach ($result in $driftedNetworkInterfaces) {
                    "{0}: Network Controller is not aware virtual machine {1} exists on {2}`n`tThis may be a transient exception that can be safely ignored if no issues reported with virtual machine." `
                    -f $result.macAddress, $result.vmName, $result.hyperv_host | Trace-Output -Level:Warning
                }
            }
            else {
                # in this scenario, the serverref and hypervisor server values are mismatched indicating
                # we have a hard drift between network controller and dataplane, which would result in stale/outdated policies
                foreach ($result in $driftedNetworkInterfaces) {
                    "{0}: Network Controller believes {1} exists on {2} while hypervisor is reporting it exists on {3}" `
                    -f $result.macAddress, $result.vmName, $result.nc_host, $result.hyperv_host | Trace-Output -Level:Warning

                    [void]$arrayList.Add($result)
                    $issueDetected = $true
                }
            }
        }

        return [PSCustomObject]@{
            Result = $issueDetected
            Properties = $arrayList
        }
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-ProviderNetwork {
    <#
    .SYNOPSIS
        Performs ICMP tests across the computers defined to confirm that jumbo packets are able to successfully traverse between the provider addresses on each host
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validating Provider Address network has connectivity across the SDN dataplane" | Trace-Output

        $providerAddresses = (Get-SdnProviderAddress -ComputerName $SdnEnvironmentObject.ComputerName -Credential $Credential).ProviderAddress
        if ($null -eq $providerAddresses){
            "No provider addresses were found on the hosts specified. This may be expected if tenant workloads have not yet been deployed." | Trace-Output -Level:Warning
        }

        if ($providerAddresses) {
            $connectivityResults = Invoke-PSRemoteCommand -ComputerName $SdnEnvironmentObject.ComputerName -Credential $Credential -Scriptblock {
                param([Parameter(Position = 0)][String[]]$param1)
                Test-SdnProviderAddressConnectivity -ProviderAddress $param1
            } -ArgumentList $providerAddresses

            foreach($computer in $connectivityResults | Group-Object PSComputerName){
                foreach($destinationAddress in $computer.Group){
                    $jumboPacketResult = $destinationAddress | Where-Object {$_.BufferSize -gt 1472}
                    $standardPacketResult = $destinationAddress | Where-Object {$_.BufferSize -le 1472}

                    if($destinationAddress.Status -ine 'Success'){
                        $sdnHealthObject.Result = 'FAIL'

                        # if both jumbo and standard icmp tests fails, indicates a failure in the physical network
                        if($jumboPacketResult.Status -ieq 'Failure' -and $standardPacketResult.Status -ieq 'Failure'){
                            $sdnHealthObject.Remediation = "Ensure ICMP enabled. If issue persists, investigate network connectivity."
                            "Cannot ping {0} from {1} ({2})." `
                            -f $destinationAddress[0].DestinationAddress, $computer.Name, $destinationAddress[0].SourceAddress | Trace-Output -Level:Exception
                        }

                        # if standard MTU was success but jumbo MTU was failure, indication that jumbo packets or encap overhead has not been setup and configured
                        # either on the physical nic or within the physical switches between the provider addresses
                        if($jumboPacketResult.Status -ieq 'Failure' -and $standardPacketResult.Status -ieq 'Success'){
                            $sdnHealthObject.Remediation = "Ensure physical switches and network interfaces support 1660 byte payload using Jumbo Packets or EncapOverhead"
                            "Cannot send jumbo packets to {0} from {1} ({2})." `
                            -f $destinationAddress[0].DestinationAddress, $computer.Name, $destinationAddress[0].SourceAddress | Trace-Output -Level:Exception
                        }
                    }
                    else {
                        "Successfully sent jumbo packet to {0} from {1} ({2})" `
                        -f $destinationAddress[0].DestinationAddress, $computer.Name, $destinationAddress[0].SourceAddress | Trace-Output
                    }

                    $array += $destinationAddress
                }
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-ResourceConfigurationState {
    <#
    .SYNOPSIS
        Validate that the configurationState and provisioningState is Success
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $NcRestCredential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validating configuration and provisioning state of {0}" -f $SdnEnvironmentObject.Role.ResourceName | Trace-Output

        $sdnResources = Get-SdnResource -NcUri $SdnEnvironmentObject.NcUrl.AbsoluteUri -Resource $SdnEnvironmentObject.Role.ResourceName -Credential $NcRestCredential
        foreach($object in $sdnResources){
            # examine the provisioning state of the resources and display errors to the screen
            if ($object.properties.provisioningState -ine 'Succeeded') {
                $sdnHealthObject.Result = 'FAIL'
                $sdnHealthObject.Remediation = 'Examine the Network Controller logs to determine why resource provisioning failed and take corrective measures.'

                "{0} is reporting provisioning state: {1}" -f $object.resourceRef, $object.properties.provisioningState | Trace-Output -Level:Exception
            }

            # examine the configuration state of the resources and display errors to the screen
            elseif($object.properties.configurationState.status -ine 'Success'){

                # gateways leverage an Uninitialized for when a gateway is passive and not hosting any virtual gateways
                # in this scenario, we can skip this status event
                if($object.properties.configurationState.status -ieq 'Uninitialized'){
                    continue
                }

                $sdnHealthObject.Result = 'FAIL'
                $sdnHealthObject.Remediation = 'Examine the detailedInfo property and take corrective action.'
                "{0} is reporting configurationState status: {1}" -f $object.resourceRef, $object.properties.configurationState.Status | Trace-Output -Level:Exception
            }

            $details = [PSCustomObject]@{
                resourceRef = $object.resourceRef
                provisioningState = $object.properties.provisioningState
                configurationState = $object.properties.configurationState
            }

            $array += $details
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-ScheduledTaskEnabled {
    <#
    .SYNOPSIS
        Ensures the scheduled task responsible for etl compression is enabled and running
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    $scriptBlock = {
        try {
            $result = Get-ScheduledTask -TaskName 'SDN Diagnostics Task' -ErrorAction Stop
            return [PSCustomObject]@{
                TaskName = $result.TaskName
                State = $result.State.ToString()
            }
        }
        catch {
            return [PSCustomObject]@{
                TaskName = 'SDN Diagnostics Task'
                State = 'Not Available'
            }
        }
    }

    try {
        $scheduledTaskReady = Invoke-PSRemoteCommand -ComputerName $SdnEnvironmentObject.ComputerName -Credential $Credential -ScriptBlock $scriptBlock -AsJob -PassThru
        foreach ($result in $scheduledTaskReady) {
            if ($result.State -ine 'Ready' -and $result.State -ine 'Running') {
                "SDN Diagnostics Task state is {0} on {1}, which may result in uncontrolled log growth" -f $result.State, $result.PSComputerName | Trace-Output -Level:Exception
                $sdnHealthObject.Result = 'FAIL'
            }

            $array += [PSCustomObject]@{
                State = $result.State
                Computer = $result.PSComputerName
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-ServerHostId {
    <#
    .SYNOPSIS
        Queries the NCHostAgent HostID registry key value across the hypervisor hosts to ensure the HostID matches known InstanceID results from NC Servers API.
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $NcRestCredential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validating Server HostID registry matches known InstanceIDs from Network Controller Servers API." | Trace-Output

        $scriptBlock = {
            $result = Get-ItemProperty -Path 'HKLM:\SYSTEM\CurrentControlSet\Services\NcHostAgent\Parameters' -Name 'HostId' -ErrorAction SilentlyContinue
            return $result.HostID
        }

        $servers = Get-SdnResource -NcUri $SdnEnvironmentObject.NcUrl.AbsoluteUri -Resource $SdnEnvironmentObject.Role.ResourceName -Credential $NcRestCredential
        $hostId = Invoke-PSRemoteCommand -ComputerName $SdnEnvironmentObject.ComputerName -Credential $Credential -ScriptBlock $scriptBlock -AsJob -PassThru
        foreach($id in $hostId){
            if($id -inotin $servers.instanceId){
                "{0}'s HostID {1} does not match known instanceID results in Network Controller Server REST API" -f $id.PSComputerName, $id | Trace-Output -Level:Warning
                $sdnHealthObject.Result = 'FAIL'

                $object = [PSCustomObject]@{
                    HostID = $id
                    Computer = $id.PSComputerName
                }

                $array += $object
            }
            else {
                "{0}'s HostID {1} matches known InstanceID in Network Controller Server REST API" -f $id.PSComputerName, $id | Trace-Output -Level:Verbose
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-ServiceFabricPartitionDatabaseSize {
    <#
    .SYNOPSIS
        Validate the Service Fabric partition size for each of the services running on Network Controller.
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validate the size of the Service Fabric Partition Databases for Network Controller services" | Trace-Output

        $ncNodes = Get-SdnServiceFabricNode -NetworkController $SdnEnvironmentObject.ComputerName -Credential $credential
        if($null -eq $ncNodes){
            throw New-Object System.NullReferenceException("Unable to retrieve service fabric nodes")
        }

        foreach($node in $ncNodes){
            $ncApp = Invoke-SdnServiceFabricCommand -NetworkController $SdnEnvironmentObject.ComputerName -Credential $Credential -ScriptBlock {
                param([Parameter(Position = 0)][String]$param1)
                Get-ServiceFabricDeployedApplication -ApplicationName 'fabric:/NetworkController' -NodeName $param1
            } -ArgumentList @($node.NodeName.ToString())

            $ncAppWorkDir = $ncApp.WorkDirectory
            if($null -eq $ncAppWorkDir){
                throw New-Object System.NullReferenceException("Unable to retrieve working directory path")
            }

            # Only stateful service have the database file
            $ncServices = Get-SdnServiceFabricService -NetworkController $SdnEnvironmentObject.ComputerName -Credential $Credential | Where-Object {$_.ServiceKind -eq "Stateful"}

            foreach ($ncService in $ncServices){
                $replica = Get-SdnServiceFabricReplica -NetworkController $SdnEnvironmentObject.ComputerName -ServiceName $ncService.ServiceName -Credential $Credential | Where-Object {$_.NodeName -eq $node.NodeName}
                $imosStorePath = Join-Path -Path $ncAppWorkDir -ChildPath "P_$($replica.PartitionId)\R_$($replica.ReplicaId)\ImosStore"
                $imosStoreFile = Invoke-PSRemoteCommand -ComputerName $node.NodeName -Credential $Credential -ScriptBlock {
                    param([Parameter(Position = 0)][String]$param1)
                    if (Test-Path -Path $param1) {
                        return (Get-Item -Path $param1)
                    }
                    else {
                        return $null
                    }
                } -ArgumentList @($imosStorePath)

                if($null -ne $imosStoreFile){
                    $formatedByteSize = Format-ByteSize -Bytes $imosStoreFile.Length

                    $imosInfo = [PSCustomObject]@{
                        Node = $node.NodeName
                        Service = $ncService.ServiceName
                        ImosSize = $formatedByteSize.GB
                    }

                    # if the imos database file exceeds 4GB, want to indicate failure as it should not grow to be larger than this size
                    if([float]$formatedByteSize.GB -gt 4){
                        "[{0}] Service {1} is reporting {2} GB in size" -f $node.NodeName, $ncService.ServiceName, $formatedByteSize.GB | Trace-Output -Level:Warning

                        $sdnHealthObject.Result = 'FAIL'
                    }
                    else {
                        "[{0}] Service {1} is reporting {2} GB in size" -f $node.NodeName, $ncService.ServiceName, $formatedByteSize.GB | Trace-Output -Level:Verbose
                    }

                    $array += $imosInfo
                }
                else {
                    "No ImosStore file for service {0} found on node {1} from {2}" -f $ncService.ServiceName, $node.NodeName, $imosStorePath | Trace-Output -Level:Warning
                }
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-ServiceState {
    <#
    .SYNOPSIS
        Confirms that critical services for gateway are running
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()
    $serviceStateResults = @()

    try {
        [string[]]$services = $SdnEnvironmentObject.Role.Properties.Services.Keys
        "Validating {0} service state for {1}" -f ($services -join ', '), ($SdnEnvironmentObject.ComputerName -join ', ') | Trace-Output

        $scriptBlock = {
            param([Parameter(Position = 0)][String]$param1)

            $result = Get-Service -Name $param1 -ErrorAction SilentlyContinue
            return $result
        }

        foreach ($service in $services) {
            $serviceStateResults += Invoke-PSRemoteCommand -ComputerName $SdnEnvironmentObject.ComputerName -Credential $Credential -Scriptblock $scriptBlock -ArgumentList $service
        }

        foreach($result in $serviceStateResults){
            $array += $result

            if($result.Status -ine 'Running'){
                $sdnHealthObject.Result = 'FAIL'
                $sdnHealthObject.Remediation = 'Start the service(s).'

                "{0} is {1} on {2}" -f $result.Name, $result.Status, $result.PSComputerName | Trace-Output -Level:Warning
            }
            else {
                "{0} is {1} on {2}" -f $result.Name, $result.Status, $result.PSComputerName | Trace-Output -Level:Verbose
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-VfpDuplicatePort {
    <#
    .SYNOPSIS
        Validate there are no ports within VFP layer that may have duplicate MAC addresses.
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validate no duplicate MAC addresses for ports within Virtual Filtering Platform (VFP)" | Trace-Output

        $vfpPorts = Get-SdnVfpVmSwitchPort -ComputerName $SdnEnvironmentObject.ComputerName -Credential $Credential
        $duplicateObjects = $vfpPorts | Where-Object {$_.MACaddress -ne '00-00-00-00-00-00' -and $null -ne $_.MacAddress} | Group-Object -Property MacAddress | Where-Object {$_.Count -ge 2}
        if($duplicateObjects){
            $array += $duplicateObjects
            $sdnHealthObject.Result = 'FAIL'

            # since there can be multiple grouped objects, we need to enumerate each duplicate group
            foreach($obj in $duplicateObjects){
                "Located {0} VFP ports associated with {1}:`r`n`n{2}`r`n" -f $obj.Count, $obj.Name, `
                    ($obj.Group `
                    | Select-Object @{n="Portname";e={"`t$($_.Portname)"}} `
                    | Select-Object -ExpandProperty Portname `
                    | Out-String `
                ) | Trace-Output -Level:Warning
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Test-VMNetAdapterDuplicateMacAddress {
    <#
    .SYNOPSIS
        Validate there are no adapters within hyper-v dataplane that may have duplicate MAC addresses.
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [SdnFabricHealthObject]$SdnEnvironmentObject,

        [Parameter(Mandatory = $false)]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty
    )

    $sdnHealthObject = [SdnHealth]::new()
    $array = @()

    try {
        "Validate no duplicate MAC addresses for network adapters within Hyper-V" | Trace-Output

        $vmNetAdapters = Get-SdnVMNetworkAdapter -ComputerName $SdnEnvironmentObject.ComputerName -AsJob -PassThru -Timeout 900 -Credential $Credential
        $duplicateObjects = $vmNetAdapters | Group-Object -Property MacAddress | Where-Object {$_.Count -ge 2}
        if($duplicateObjects){
            $array += $duplicateObjects
            $sdnHealthObject.Result = 'FAIL'

            # since there can be multiple grouped objects, we need to enumerate each duplicate group
            foreach($obj in $duplicateObjects){
                "Located {0} virtual machines associated with MAC address {1}:`r`n`n{2}`r`n" -f $obj.Count, $obj.Name, `
                    ($obj.Group `
                    | Select-Object @{n="VMName";e={"`t$($_.VMName)"}} `
                    | Select-Object -ExpandProperty VMName `
                    | Out-String `
                ) | Trace-Output -Level:Warning
            }
        }

        $sdnHealthObject.Properties = $array
        return $sdnHealthObject
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Debug-SdnFabricInfrastructure {
    <#
    .SYNOPSIS
        Executes a series of fabric validation tests to validate the state and health of the underlying components within the SDN fabric.
    .PARAMETER NetworkController
        Specifies the name or IP address of the network controller node on which this cmdlet operates. The parameter is optional if running on network controller node.
    .PARAMETER ComputerName
        Type the NetBIOS name, an IP address, or a fully qualified domain name of one or more remote computers.
    .PARAMETER Role
        The specific SDN role(s) to perform tests and validations for. If ommitted, defaults to all roles.
    .PARAMETER Credential
        Specifies a user account that has permission to perform this action. The default is the current user.
    .PARAMETER NcRestCredential
        Specifies a user account that has permission to access the northbound NC API interface. The default is the current user.
    .EXAMPLE
        PS> Debug-SdnFabricInfrastructure
    .EXAMPLE
        PS> Debug-SdnFabricInfrastructure -NetworkController 'NC01' -Credential (Get-Credential) -NcRestCredential (Get-Credential)
    #>

    [CmdletBinding(DefaultParameterSetName = 'Role')]
    param (
        [Parameter(Mandatory = $false, ParameterSetName = 'Role')]
        [Parameter(Mandatory = $false, ParameterSetName = 'ComputerName')]
        [System.String]$NetworkController = $(HostName),

        [Parameter(Mandatory = $false, ParameterSetName = 'Role')]
        [SdnDiag.Common.Helper.SdnRoles[]]$Role = ('Gateway','LoadBalancerMux','NetworkController','Server'),

        [Parameter(Mandatory = $true, ParameterSetName = 'ComputerName')]
        [System.String[]]$ComputerName,

        [Parameter(Mandatory = $false, ParameterSetName = 'Role')]
        [Parameter(Mandatory = $false, ParameterSetName = 'ComputerName')]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $Credential = [System.Management.Automation.PSCredential]::Empty,

        [Parameter(Mandatory = $false, ParameterSetName = 'Role')]
        [Parameter(Mandatory = $false, ParameterSetName = 'ComputerName')]
        [System.Management.Automation.PSCredential]
        [System.Management.Automation.Credential()]
        $NcRestCredential = [System.Management.Automation.PSCredential]::Empty
    )

    $script:SdnDiagnostics_Health.Cache = $null

    try {
        if (-NOT ($PSBoundParameters.ContainsKey('NetworkController'))) {
            $config = Get-SdnModuleConfiguration -Role 'NetworkController'
            $confirmFeatures = Confirm-RequiredFeaturesInstalled -Name $config.windowsFeature
            if (-NOT ($confirmFeatures)) {
                "The current machine is not a NetworkController, run this on NetworkController or use -NetworkController parameter to specify one" | Trace-Output -Level:Warning
                return # don't throw exception, since this is a controlled scenario and we do not need stack exception tracing
            }
        }

        $environmentInfo = Get-SdnInfrastructureInfo -NetworkController $NetworkController -Credential $Credential -NcRestCredential $NcRestCredential
        if($null -eq $environmentInfo){
            throw New-Object System.NullReferenceException("Unable to retrieve environment details")
        }

        # if we opted to specify the ComputerName rather than Role, we need to determine which role
        # the computer names are associated with
        if ($PSCmdlet.ParameterSetName -ieq 'ComputerName') {
            $Role = @()
            $ComputerName | ForEach-Object {
                $computerRole = $_ | Get-SdnRole -EnvironmentInfo $environmentInfo
                if ($computerRole) {
                    $Role += $computerRole
                }
            }
        }

        $Role = $Role | Sort-Object -Unique
        foreach ($object in $Role) {
            "Processing tests for {0} role" -f $object | Trace-Output
            $sdnFabricDetails = [SdnFabricHealthObject]::new()
            $sdnFabricDetails.NcUrl = $environmentInfo.NcUrl

            $config = Get-SdnModuleConfiguration -Role $object.ToString()
            $sdnFabricDetails.Role = $config

            if ($ComputerName) {
                $sdnFabricDetails.ComputerName = $ComputerName
            }
            else {
                $sdnFabricDetails.ComputerName = $environmentInfo[$object.ToString()]
            }

            $restApiParams = @{
                SdnEnvironmentObject    = $sdnFabricDetails
                NcRestCredential        = $NcRestCredential
            }

            $computerCredParams = @{
                SdnEnvironmentObject    = $sdnFabricDetails
                Credential              = $Credential
            }

            $computerCredAndRestApiParams = @{
                SdnEnvironmentObject    = $sdnFabricDetails
                NcRestCredential        = $NcRestCredential
                Credential              = $Credential
            }

            # perform the health validations for the appropriate roles that were specified directly
            # or determined via which ComputerNames were defined
            switch ($object) {
                'Gateway' {
                    $objectArray += @{
                        Gateway = @(
                            Test-ResourceConfigurationState @restApiParams
                            Test-ServiceState @computerCredParams
                            Test-ScheduledTaskEnabled @computerCredParams
                        )
                    }
                }

                'LoadBalancerMux' {
                    $objectArray += @{
                        LoadBalancerMux = @(
                            Test-ResourceConfigurationState @restApiParams
                            Test-ServiceState @computerCredParams
                            Test-ScheduledTaskEnabled @computerCredParams
                        )
                    }
                }

                'NetworkController' {
                    $objectArray += @{
                        NetworkController = @(
                            Test-ServiceState @computerCredParams
                            Test-ServiceFabricPartitionDatabaseSize @computerCredParams
                            Test-NetworkInterfaceAPIDuplicateMacAddress @restApiParams
                            Test-ScheduledTaskEnabled @computerCredParams
                        )
                    }
                }

                'Server' {
                    $objectArray += @{
                        Server = @(
                            Test-EncapOverhead @computerCredParams
                            Test-ProviderNetwork @computerCredParams
                            Test-ResourceConfigurationState @restApiParams
                            Test-ServiceState @computerCredParams
                            Test-ServerHostId @computerCredAndRestApiParams
                            Test-VfpDuplicatePort @computerCredParams
                            Test-VMNetAdapterDuplicateMacAddress @computerCredParams
                            Test-HostRootStoreNonRootCert @computerCredParams
                            Test-ScheduledTaskEnabled @computerCredParams
                        )
                    }
                }
            }
        }

        if ($objectArray) {
            $script:SdnDiagnostics_Health.Cache = $objectArray

            "Results for fabric health have been saved to cache for further analysis. Use 'Get-SdnFabricInfrastructureResult' to examine the results." | Trace-Output
            return $script:SdnDiagnostics_Health.Cache
        }
    }
    catch {
        "{0}`n{1}" -f $_.Exception, $_.ScriptStackTrace | Trace-Output -Level:Error
    }
}

function Get-SdnFabricInfrastructureResult {
    <#
        .SYNOPSIS
            Returns the results that have been saved to cache as part of running Debug-SdnFabricInfrastructure.
        .PARAMETER Role
            The name of the SDN role that you want to return test results from within the cache.
        .PARAMETER Name
            The name of the test results you want to examine.
        .EXAMPLE
            PS> Get-SdnFabricInfrastructureResult
        .EXAMPLE
            PS> Get-SdnFabricInfrastructureResult -Role Server
        .EXAMPLE
            PS> Get-SdnFabricInfrastructureResult -Role Server -Name 'Test-ServiceState'
    #>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $false)]
        [SdnDiag.Common.Helper.SdnRoles]$Role,

        [Parameter(Mandatory = $false)]
        [System.String]$Name
    )

    $cacheResults = $script:SdnDiagnostics_Health.Cache

    if ($PSBoundParameters.ContainsKey('Role')) {
        if ($cacheResults) {
            $cacheResults = $cacheResults.$($Role.ToString())
        }
    }

    if ($PSBoundParameters.ContainsKey('Name')) {
        if ($cacheResults) {
            $cacheResults = $cacheResults | Where-Object {$_.Name -eq $Name}
        }
    }

    return $cacheResults
}