Clone a Standard vSwitch from one ESXi Host to Another

One of my customers is standardizing the configurations on their HP C7000 enclosures (they've been set up at various sites by various administrators with varying involvement from the architecture team).  As such, we need to stand up some temporary resources so that we can take down the main enclosure for reconfiguration.  That's fine, we can easily ship a smaller enclosure to each site for temporary compute resources.  Some of the sites are using Standard vSwitches, so we need to be able to quickly copy the networking configuration over from their existing blades to these new, slightly different blades.  As I see it, we had 2 good options:

1) Capture a Host Profile with the desired vSwitch configuration.  Delete every other component of the Host Profile so that only the networking section is applied; design the new ESXi hosts so that the vSwitches'll work with the old vmnic-to-vswitch configurations.

2) Write a script to clone the vSwitch from ones ESXi host to another.

If you know anything about me, you can probably guess that I went with the scripting option.  Host profiles are great and all, but I like the amount of control that a script gives me, as it allows me to know exactly what is happening.  So, after a bit of work one morning, I came up with the script below.

The syntax is pretty straight forward - it takes 3 arguments.  It needs to know the source ESXi host, the name of the vSwitch on that ESXi host and the name of the destination ESXi host.  It'll then run through and create that same vSwitch on the destination.  If that vSwitch already exists on the destination, it will warn the user and prompt for permission to continue.  If permission is granted, it will only create new Port Groups on that vSwitchl it will not adjust any Port Groups that already exist.

As always, this is posted for educational purposes.  While it worked for me in this particular situation, that's no guarantee that it'll work for you, yadda yadda yadda.  If you find/fix any bugs, please let me know and I'll happily include your improvements!

#Copies one host's standard vSwitch to another host
#Author: Jason Coleman (virtuallyjason.blogspot.com)
#Usage: Clone-VSS.ps1 -s [the name of the ESX host to copy the vSwitch from] -v [the name of the vSwitch to copy] -d [the name of the ESX host to copy the vSwitch to]
param
(
   [alias("s")]
   [string]$sourceHostString = $(read-host -Prompt "Enter the source Host"),
   [alias("v")]
   [string]$sourceVSwitchString = $(read-host -Prompt "Enter the Source Standard Virtual Switch"),
   [alias("d")]
   [string]$destinationHostString = $(read-host -Prompt "Enter the Destination Host")
)

#Get the destination host
$thisHost = get-vmhost $destinationHostString

#Get the source vSwitch and do error checking
$sVSwitch = get-vmhost $sourceHostString | get-virtualswitch -name $sourceVSwitchString -errorAction silentlycontinue
if (!($sVSwitch))
{
   write-host "$sourceVSwitchString was not found on $sourceHostString" -foreground "red"
   exit 1
}
if ($sVSwitch.count -ne 1)
{
   write-host "'$sourceVswitchString' returned multiple vSwitches; please use a more specific string." -foreground "red"
   $sVSwitch
   exit 4
}
if ($thisHost | get-virtualSwitch -name $sourceVSwitchString -errorAction silentlycontinue)
{   
   if ((($thisHost | get-virtualSwitch -name $sourceVSwitchString).uid) -like "*DistributedSwitch*")
   {
      write-host "$sourceVSwitchString is a Distributed vSwitch, exiting." -foreground "red"
      exit 3
   }
   $continue = read-host "vSwitch $sourceVSwitchString already exists on $destinationHostString; continue? [yes|no]"
   if (!($continue -like "y*"))
   {
      exit 2
   }
}
else
{
   #If the VSS doesn't already exist, create it
   $thisHost | new-virtualSwitch -name $sVSwitch.name > $null
}

#Make new Port Groups on the VSS
$destSwitch = $thisHost | get-virtualSwitch -name $sVSwitch.name
foreach ($thisPG in ($sVSwitch | get-virtualportgroup))
{
   #Skip this Port Group if it already exists on the destination vSwitch
   if ($destSwitch | get-virtualportgroup -name "$($thisPG.Name)" -errorAction silentlycontinue)
   {
      echo "$($thisPG.Name) already exists, skipping."
   }
   else
   {
      echo "Creating Port Group: $($thisPG.Name)."
      new-virtualportgroup -virtualswitch $destSwitch -name "$($thisPG.Name)" > $null
      #Assign a VLAN tag if there is one on the source Port Group
      if ($thisPG.vlanid -ne 0)
      {
         get-virtualportgroup -virtualswitch $destSwitch -name "$($thisPG.Name)" | Set-VirtualPortGroup -vlanid $thisPG.vlanid > $null
      }      
   }
}