On Hypervisor.fr, a blog you should have in your RSS reader, there were already posts on how to configure the dvSwitch healthcheck and how to do a dvSwitch configuration rollback from PowerCLI. But till now, as far as I know, there were no functions to provide the dvSwitch export/restore functionality.

Time to make this useful functionality available for the “PowerCLI automation crowd”

The Script

function Export-dvSwConfig {
<#  
.SYNOPSIS  Export a dvSwitch configuration  
.DESCRIPTION The function will export the dvSwitch
  configuration(s) to a file. 
  This requires at least vSphere 5.1.
.NOTES  Author:  Luc Dekens  
.PARAMETER dvSw
  The dvSwitch(es) whose config you want to export.
.PARAMETER Path
  The path to a filename where the config should be
  written to.
.PARAMETER IncludePortgroups
  Switch that indicates if only the dvSwitch configuration
  or the dvSwitch and all portgroups should be exported
.EXAMPLE
  PS> Export-dvSwConfig -Path C:\dvswconfig.xml -IncludePortgroups
.EXAMPLE
   PS> $dvsw | Export-dvSwConfig -Path C:\file.xml
#>

  param(
    [CmdletBinding()]
    [Parameter(Mandatory=$true,ValueFromPipeline=$true)]
    [PSObject]$dvSw,
    [String]$Path,
    [Switch]$IncludePortgroups = $false
  )

  begin {
    $si = Get-View ServiceInstance
    $dvSwMgr = Get-View $si.Content.dvSwitchManager
    $selectionTab = @()
  }

  process{
    if($dvSw -is [System.String]){
      $dvSw = Get-VirtualSwitch -Distributed -Name $dvsw
    }
    if($IncludePortgroups){
      $selection = New-Object VMware.Vim.DVPortgroupSelection
      $selection.portgroupKey = Get-VirtualPortGroup -VirtualSwitch $dvsw | %{$_.Key}
      $selection.dvsUuid = $dvsw.ExtensionData.Uuid
      $selectionTab += $selection
    }
    $selection = New-Object VMware.Vim.DVSSelection
    $selection.dvsUuid = $dvsw.ExtensionData.Uuid
    $selectionTab += $selection
  }

  end{
    $dvswSaved = $dvSwMgr.DVSManagerExportEntity($selectionTab)
    $dvswSaved | Export-Clixml -Path $Path
  }
}

function Restore-dvSwConfig {
<#  
.SYNOPSIS  Restores a dvSwitch configuration  
.DESCRIPTION The function will import the dvSwitch
  configuration(s) from a file. 
  This requires at least vSphere 5.1.
.NOTES  Author:  Luc Dekens  
.PARAMETER Path
  The path to a filename where the config is stored.
.PARAMETER IncludePortgroups
  Switch that indicates if only the dvSwitch configuration
  or the dvSwitch and all portgroups should be exported
.EXAMPLE
  PS> Restore-dvSwConfig -Path C:\dvswconfig.xml
#>

  param(
    [CmdletBinding()]
    [Parameter(Mandatory=$true)]
    [String]$Path,
    [Switch]$IncludePortgroups = $false
  )

  process {

    $si = Get-View ServiceInstance
    $dvSwMgr = Get-View $si.Content.dvSwitchManager

    $dvswImport = @()
    Import-Clixml -Path $Path | 
    where{($IncludePortgroups -and $_.EntityType -eq "distributedVirtualPortgroup") -or 
        $_.EntityType -eq "distributedVirtualSwitch"} | %{
      $info = New-Object VMware.Vim.EntityBackupConfig
      $info.ConfigBlob = $_.ConfigBlob
      $info.ConfigVersion = $_.ConfigVersion
      $info.Container = $_.Container
      $info.EntityType = $_.EntityType
      $info.Key = $_.Key
      $info.Name = $_.Name
      $dvswImport += $info
    }
    $dvSwMgr.DVSManagerImportEntity($dvswImport,"applyToEntitySpecified") | Out-Null
  }
}

Annotations

Line 25,37-39: My cheap way of emulating the OBN principle.

Line 40-45: If the IncludePortgroups switch is $true, the configuration of the distributed virtual portgroups on the dvSwitch will also be exported.

Line 53: The object that is returned by the call to the DVSManagerExportEntity method is written to a file with the Export-Clixml cmdlet.

Line 90-95: The reason why the function copies the properties one-by-one instead of doing the complete object in one go is due to serialisation-deserialisation process that you get with the Export- and Import-Clixml cmdlets. The imported objects all have a type that has a Deserialized suffix in front. There are ways to avoid this, but the is a simple and readable solution.

Sample Usage

The use of the functions is quite simple.

$dvSw = Get-VirtualSwitch -Distributed -Name dvSw1
Export-dvSwConfig -dvSw $dvSw  -Path C:\dvSw1.xml

By default this will save the configuration of the dvSwitch, but not the portgroups on the dvSwitch.
To include the portgroups, you will have to use the IncludePortgroups switch.

$dvSw = Get-VirtualSwitch -Distributed -Name dvSw1
Export-dvSwConfig -dvSw $dvSw  -Path C:\dvSw1.xml -IncludePortgroups

You can also use the function in a pipeline like this

Get-VirtualSwitch -Distributed -Name dvSw2 | Export-dvSwConfig -Path C:\dvSw2.xm2

As you can read in the Annotations, the function uses the PowerShell Export-Clixml cmdlet to write the configuration to a file.
Note that this format is NOT COMPATIBLE with the file format used in the vSphere Web Client.

If you want to emulate that format, you have a look at William Lam‘s post Automate Backups of VDS & Distributed Portgroup Configurations in vSphere 5.1.

To restore the configuration of a dvSwitch, and optionally the connected portgroups, is quite similar. A restore can be executed like this.

Restore-dvSwConfig -Path C:\dvsw1.xml -IncludePortgroups

Notice that the IncludePortgroups switch defines if you want to restore the configuration of the portgroups on the dvSwitch as well.

The 2 methods that are used by these functions have several other possibilities. You can for example also use these files to Import a dvSwitch, but that will be for a later post

Enjoy !