Use this script to assign Splunk for VMware vCenter permisisons to a specified Active Directory account

Add-SplunkVmwarePermission.ps1

<#
.SYNOPSIS
    Use this script to assign Splunk for VMware vCenter permisisons to a specified Active Directory account
.DESCRIPTION
    Use this script as a companion to performing the installation steps for Splunk for VMware. It is
    necessary to first create a service account in Active Directory to which the required permissions
    are then assigned. This script will assign the permissions to all visible datacenters. To assign
    permissions across multiple vCenter servers, login to them first by using the Connect-ViServer
    cmdlet with the AllLinked parameter (assuming that you are using the Linked mode feature of vCenter
    Server.)
.NOTES    
    This script requires VMware PowerCLI which can be obtained from http://vmware.com/go/powercli.
.PARAMETER UserId
    The user account to which permissions will be assigned. Must be in the format "domain\username".
.PARAMETER RoleName
    The role name to be created within vCenter. Defaults to "Splunker" if not specified.
.EXAMPLE
  Connect-ViServer -Server "vcenter.company.com" -AllLinked   
  Add-SplunkVmwarePermission -UserId "domain\splunksvc" -RoleName "splunk"
.LINK
    http://docs.splunk.com/Documentation/VMW/latest/Install/Createserviceaccounts
.OUTPUTS
    VMware.VimAutomation.ViCore.Impl.V1.PermissionManagement.PermissionImpl
#>

param (
    [Parameter(Mandatory=$true,
        HelpMessage="Enter Active Directory UserID in the format domain\userID.")]
    [ValidatePattern("\w+\\\w+")]
    [string]$UserId,
    [string]$RoleName = 'Splunker'
)

Add-PSSnapin VMware.VimAutomation.Core # Required to execute below cmdlets

# Array containing names of required privileges for the VMware App
$ReqPriv = @(
    "System.Anonymous"
    "System.View",
    "System.Read",
    "Global.Licenses",
    "Global.Diagnostics",
    "Global.Settings",
    "Host.Config.HyperThreading",
    "Host.Config.Storage",
    "Host.Config.NetService",
    "Host.Config.Memory",
    "Host.Config.Network",
    "Host.Config.Snmp",
    "Host.Config.Power",
    "VirtualMachine.Provisioning.ReadCustSpecs",
    "Sessions.TerminateSession"
)
$PrivObj = Get-VIPrivilege -Id $ReqPriv # Retrieve object representing required privileges
Write-Verbose "Privileges: $PrivObj"
$RoleObj = New-VIRole -Name $RoleName -Privilege $PrivObj # Create new VI role with required privileges
Write-Verbose "Role Object: $RoleObj"
$DCObj = Get-Datacenter # The object(s) to which we will assign permissions
Write-Verbose "Datacenter Object(s): $DCObj"
New-VIPermission -Entity $DCObj -Principal $UserId -Role $RoleObj -Propagate:$true # Perform actual permission change