xSQLServerMaxDop: Added Cluster Aware code

CHANGELOG.md

@@ -57,6 +57,10 @@
 - Changes to xSQLServerAvailabilityGroupListener
   - Fixed a problem when running the tests locally in a PowerShell console it
     would ask for parameters ([issue #897](https://github.com/PowerShell/xSQLServer/issues/897)).
+- Changes to xSQLServerMaxDop
+  - Made the resource cluster aware. When ProcessOnlyOnActiveNode is specified,
+    the resource will only determine if a change is needed if the target node
+    is the active host of the SQL Server instance ([issue #882](https://github.com/PowerShell/xSQLServer/issues/882)).
 
 ## 8.2.0.0
 

DSCResources/MSFT_xSQLServerMaxDop/MSFT_xSQLServerMaxDop.psm1

@@ -30,6 +30,9 @@ function Get-TargetResource
 
     $sqlServerObject = Connect-SQL -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName
 
+    # Is this node actively hosting the SQL instance?
+    $isActiveNode = Test-ActiveNode -ServerObject $sqlServerObject
+
     if ($sqlServerObject)
     {
         Write-Verbose -Message 'Getting the max degree of parallelism server configuration option'
@@ -40,6 +43,7 @@ function Get-TargetResource
         SQLInstanceName = $SQLInstanceName
         SQLServer       = $SQLServer
         MaxDop          = $currentMaxDop
+        IsActiveNode    = $isActiveNode
     }
 
     $returnValue
@@ -65,6 +69,10 @@ function Get-TargetResource
 
     .PARAMETER MaxDop
     A numeric value to limit the number of processors used in parallel plan execution.
+
+    .PARAMETER ProcessOnlyOnActiveNode
+    Specifies that the resource will only determine if a change is needed if the target node is the active host of the SQL Server Instance.
+    Not used in Set-TargetResource.
 #>
 function Set-TargetResource
 {
@@ -93,7 +101,11 @@ function Set-TargetResource
 
         [Parameter()]
         [System.Int32]
-        $MaxDop
+        $MaxDop,
+
+        [Parameter()]
+        [System.Boolean]
+        $ProcessOnlyOnActiveNode
     )
 
     $sqlServerObject = Connect-SQL -SQLServer $SQLServer -SQLInstanceName $SQLInstanceName
@@ -166,6 +178,9 @@ function Set-TargetResource
 
     .PARAMETER MaxDop
     A numeric value to limit the number of processors used in parallel plan execution.
+
+    .PARAMETER ProcessOnlyOnActiveNode
+    Specifies that the resource will only determine if a change is needed if the target node is the active host of the SQL Server Instance.
 #>
 function Test-TargetResource
 {
@@ -195,7 +210,11 @@ function Test-TargetResource
 
         [Parameter()]
         [System.Int32]
-        $MaxDop
+        $MaxDop,
+
+        [Parameter()]
+        [System.Boolean]
+        $ProcessOnlyOnActiveNode
     )
 
     Write-Verbose -Message 'Testing the max degree of parallelism server configuration option'
@@ -206,13 +225,24 @@ function Test-TargetResource
     }
 
     $currentValues = Get-TargetResource @parameters
+
     $getMaxDop = $currentValues.MaxDop
     $isMaxDopInDesiredState = $true
 
+    <#
+        If this is supposed to process only the active node, and this is not the
+        active node, don't bother evaluating the test.
+    #>
+    if ( $ProcessOnlyOnActiveNode -and -not $getTargetResourceResult.IsActiveNode )
+    {
+        New-VerboseMessage -Message ( 'The node "{0}" is not actively hosting the instance "{1}". Exiting the test.' -f $env:COMPUTERNAME,$SQLInstanceName )
+        return $isMaxDopInDesiredState
+    }
+
     switch ($Ensure)
     {
         'Absent'
-        {            
+        {
             if ($getMaxDop -ne 0)
             {
                 New-VerboseMessage -Message "Current MaxDop is $getMaxDop should be updated to 0"
@@ -260,17 +290,17 @@ function Test-TargetResource
 function Get-SqlDscDynamicMaxDop
 {
     $cimInstanceProc = Get-CimInstance -ClassName Win32_Processor
-    
+
     # init variables
     $numProcs = 0
     $numCores = 0
-    
+
     # Loop through returned objects
     foreach ($processor in $cimInstanceProc)
     {
         # increment number of processors
         $numProcs += $processor.NumberOfLogicalProcessors
-        
+
         # increment number of cores
         $numCores += $processor.NumberOfCores
     }

DSCResources/MSFT_xSQLServerMaxDop/MSFT_xSQLServerMaxDop.schema.mof

@@ -6,4 +6,6 @@ class MSFT_xSQLServerMaxDop : OMI_BaseResource
     [Write, Description("A numeric value to limit the number of processors used in parallel plan execution.")] Sint32 MaxDop;
     [Write, Description("The host name of the SQL Server to be configured. Default value is $env:COMPUTERNAME.")] String SQLServer;
     [Key, Description("The name of the SQL instance to be configured.")] String SQLInstanceName;
+    [Write, Description("Specifies that the resource will only determine if a change is needed if the target node is the active host of the SQL Server instance.")] Boolean ProcessOnlyOnActiveNode;
+    [Read, Description("Determines if the current node is actively hosting the SQL Server instance.")] Boolean IsActiveNode;
 };

Examples/Resources/xSQLServerMaxDop/2-SetMaxDopToAuto.ps1

@@ -2,6 +2,11 @@
 .EXAMPLE
     This example shows how to set max degree of parallelism server
     configuration option with the automatic configuration.
+
+    In the event this is applied to a Failover Cluster Instance (FCI), the
+    ProcessOnlyOnActiveNode property will tell the Test-TargetResource function
+    to evaluate if any changes are needed if the node is actively hosting the
+    SQL Server instance.
 #>
 Configuration Example
 {
@@ -19,11 +24,12 @@ Configuration Example
     {
         xSQLServerMaxDop Set_SQLServerMaxDop_ToAuto
         {
-            Ensure               = 'Present'
-            DynamicAlloc         = $true
-            SQLServer            = 'SQLServer'
-            SQLInstanceName      = 'DSC'
-            PsDscRunAsCredential = $SysAdminAccount
+            Ensure                  = 'Present'
+            DynamicAlloc            = $true
+            SQLServer               = 'SQLServer'
+            SQLInstanceName         = 'DSC'
+            PsDscRunAsCredential    = $SysAdminAccount
+            ProcessOnlyOnActiveNode = $true
         }
     }
 }

README.md

@@ -935,6 +935,14 @@ Read more about max degree of parallelism in this article
   parameter MaxDop must be set to $null or not be configured.
 * **`[Sint32]` MaxDop** _(Write)_: A numeric value to limit the number of processors
   used in parallel plan execution.
+* **`[Boolean]` ProcessOnlyOnActiveNode** _(Write)_: Specifies that the resource
+  will only determine if a change is needed if the target node is the active
+  host of the SQL Server instance.
+
+#### Read-Only Property from Get-TargetResource
+
+* **`[Boolean]` IsActiveNode** _(Read)_: Determines if the current node is
+  actively hosting the SQL Server instance.
 
 #### Examples
 

Tests/Unit/MSFT_xSQLServerMaxDop.Tests.ps1

@@ -13,6 +13,9 @@ if ( (-not (Test-Path -Path (Join-Path -Path $script:moduleRoot -ChildPath 'DSCR
 
 Import-Module (Join-Path -Path $script:moduleRoot -ChildPath 'DSCResource.Tests\TestHelper.psm1') -Force
 
+# Loading mocked classes
+Add-Type -Path ( Join-Path -Path ( Join-Path -Path $PSScriptRoot -ChildPath Stubs ) -ChildPath SMO.cs )
+
 $TestEnvironment = Initialize-TestEnvironment `
     -DSCModuleName $script:DSCModuleName `
     -DSCResourceName $script:DSCResourceName `
@@ -40,6 +43,7 @@ try
         $mockInvalidOperationForAlterMethod = $false
         $mockNumberOfLogicalProcessors      = 4
         $mockNumberOfCores                  = 4
+        $mockProcessOnlyOnActiveNode        = $true
 
         # Default parameters that are used for the It-blocks
         $mockDefaultParameters = @{
@@ -52,9 +56,9 @@ try
         $mockConnectSQL = {
             return @(
                 (
-                    New-Object Object |
-                        Add-Member -MemberType NoteProperty -Name InstanceName -Value $mockSQLServerInstanceName -PassThru |
-                        Add-Member -MemberType NoteProperty -Name ComputerNamePhysicalNetBIOS -Value $mockSQLServerName -PassThru |
+                    New-Object Object -TypeName Microsoft.SqlServer.Management.Smo.Server |
+                        Add-Member -MemberType NoteProperty -Name InstanceName -Value $mockSQLServerInstanceName -PassThru -Force |
+                        Add-Member -MemberType NoteProperty -Name ComputerNamePhysicalNetBIOS -Value $mockSQLServerName -PassThru -Force |
                         Add-Member -MemberType ScriptProperty -Name Configuration -Value {
                             return @( ( New-Object Object |
                                 Add-Member -MemberType ScriptProperty -Name MaxDegreeOfParallelism -Value {
@@ -96,6 +100,7 @@ try
 
         Describe "MSFT_xSQLServerMaxDop\Get-TargetResource" -Tag 'Get'{
             Mock -CommandName Connect-SQL -MockWith $mockConnectSQL -Verifiable
+            Mock -CommandName Test-ActiveNode -MockWith { return $mockProcessOnlyOnActiveNode } -Verifiable
 
             Context 'When the system is either in the desired state or not in the desired state' {
                 $testParameters = $mockDefaultParameters
@@ -114,6 +119,10 @@ try
                 It 'Should call the mock function Connect-SQL' {
                     Assert-MockCalled Connect-SQL -Exactly -Times 1 -Scope Context
                 }
+
+                It 'Should call the mock function Test-ActiveNode' {
+                    Assert-MockCalled Test-ActiveNode -Exactly -Times 1 -Scope Context
+                }
             }
 
             Assert-VerifiableMock
@@ -123,6 +132,10 @@ try
             BeforeEach {
                 Mock -CommandName Connect-SQL -MockWith $mockConnectSQL -Verifiable
 
+                Mock -CommandName Test-ActiveNode -MockWith {
+                    $mockProcessOnlyOnActiveNode
+                } -Verifiable
+
                 Mock -CommandName Get-CimInstance -MockWith $mockCimInstance_Win32Processor -ParameterFilter {
                     $ClassName -eq 'Win32_Processor'
                 } -Verifiable
@@ -290,6 +303,31 @@ try
                 }
             }
 
+            Context 'When the ProcessOnlyOnActiveNode parameter is passed' {
+                AfterAll {
+                    $mockProcessOnlyOnActiveNode = $true
+                }
+
+                BeforeAll {
+                    $testParameters = $mockDefaultParameters
+                    $testParameters += @{
+                        Ensure = 'Absent'
+                        ProcessOnlyOnActiveNode = $true
+                    }
+
+                    $mockProcessOnlyOnActiveNode = $false
+                }
+
+                It 'Should return $true when ProcessOnlyOnActiveNode is "$true" and the current node is not actively hosting the instance' {
+                    $result = Test-TargetResource @testParameters
+                    $result | Should -Be $true
+                }
+
+                It 'Should call the mock function Connect-SQL' {
+                    Assert-MockCalled Connect-SQL -Exactly -Times 1 -Scope Context
+                }
+            }
+
             $mockMaxDegreeOfParallelism = 0
 
             Context 'When the system is in the desired state and Ensure is set to absent' {