Comments on: vSphere permissions: export & import – Part 1

By: vCenter Roles & Permissions Export / Import scripts - Virtually Prepared

vCenter Roles & Permissions Export / Import scripts - Virtually Prepared — Thu, 19 Aug 2010 13:18:20 +0000

[...] After sifting through my pile of scripts I took to the web and headed straight for Alan Renouf’s website http://www.virtu-al.net/ . As you would expect there was an example originally instigated from a community discussion, the exact page is here, http://www.virtu-al.net/2009/06/15/vsphere-permissions-export-import-part-1/ [...]

By: Dave

Dave — Fri, 14 May 2010 15:51:42 +0000

I’m getting the same form of errors as other users.

The script runs okay, but I get continual errors along the lines of:

“You cannot call a method on a null-valued expression.
At C:\tmp\ExportRoles.ps1:85 char:22
$node.AppendChild( <<<< $tmp)”

“You cannot call a method on a null-valued expression.
At C:\tmp\ExportRoles.ps1:85 char:23
$node.SetAttribute( <<<< $name, $value)”

“You cannot call a method on a null-valued expression.
At C:\tmp\ExportRoles.ps1:85 char:44
$tmp = $global:vInventory.CreateElement( <<<< $nodeName)”

That loops for a while then I get errors like:

“Exception calling “AppendChild” with “1″ argument(s): “Object reference not set to an instance of an object.”
At C:\tmp\ExportRoles.ps1:81 char:22
$node.AppendChild( <<<< $tmp)

When carrying out the fix as mentioned by Mitchum, i get the same erros but with a new one thrown in:

“Exception calling “CreateElement” with “1″ argument(s): “The local name for elements or attributes cannot be null or an empty string.”
At C:\tmp\ExportRoles.ps1:80 char:37
$tmp = $vInventory.CreateElement( <<<< $nodeName)

The script is creating the xml file populated with the descriptors, it’s just not populating it with any of my roles or permissions.

I’m using vCenter 4.0U1 build 208111 and the PowerCli 4.0.1-208462

Any ideas?

“Exception calling “CreateElement” with “1″

By: bkboyer

bkboyer — Fri, 30 Apr 2010 15:10:03 +0000

Here’s the only part I changed to get it to work, as mentioned by Mitchum:

——-
function Get-XmlNode{
param($path)
$vInventory.SelectNodes($path)
}
[XML]$vInventory = “”
# Roles
———

By: Jase

Jase — Tue, 27 Apr 2010 19:44:27 +0000

Is there an update version of the script that works? I too am getting the same result as everyone else..
You cannot call a method on a null-valued expression.
At S:\SCRIPTS\FID_EXPORT_vc_roles.ps1:58 char:21
+ $node.SetAttribute <<<< ($name, $value)

Guess I just need to learn how to script..

Thanks!

By: Jase

Jase — Tue, 27 Apr 2010 18:38:42 +0000

Can someone post the new modified script? I’m getting the same error as everyone else. It looks like Mitchum posted a fix:
**************************
There are 2 things to have the script working:
- Remove the global type for vInventory variable
- Define the vInventory variable to be a XML object:
[XML] $vInventory = “”

Should be ok then
**************************
Can someone correct that and re-post?
Thanks for the help VMware peeps!!

By: Eugene

Eugene — Fri, 16 Apr 2010 01:27:45 +0000

Thanks a lot. Have been looking for something like this for our environment.

By: bkboyer

bkboyer — Wed, 10 Mar 2010 20:18:39 +0000

Thanks, Al, for another great script. And thanks Mitchum, that fix worked great.

One quick question from a newbie, is there any particular application, other than IE, that works well for viewing XML docs? Thanks!

By: Mark

Mark — Tue, 09 Mar 2010 19:20:18 +0000

i am running the script with this command – .\EXPORT_vc_roles.ps1 –server vcservername –username username –password “*****”

and I too get numerous errors regarding calling a method on a null-valued expression.

just a sample of the numerous errors.

You cannot call a method on a null-valued expression.
At S:\SCRIPTS\FID_EXPORT_vc_roles.ps1:58 char:21
+ $node.SetAttribute <<<< ($name, $value)
+ CategoryInfo : InvalidOperation: (SetAttribute:String) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull

Method invocation failed because [System.String] doesn't contain a method named 'Save'.
At S:\SCRIPTS\FID_EXPORT_vc_roles.ps1:88 char:17
+ $vInventory.Save <<<< ("S:\SCRIPTS\vInventory.xml")
+ CategoryInfo : InvalidOperation: (Save:String) [], RuntimeException
+ FullyQualifiedErrorId : MethodNotFound

By: Mitchum

Mitchum — Thu, 28 Jan 2010 08:21:31 +0000

There are 2 things to have the script working:
- Remove the global type for vInventory variable
- Define the vInventory variable to be a XML object:
[XML] $vInventory = “”

Should be ok then

By: kl

kl — Tue, 03 Nov 2009 15:15:12 +0000

Sie können keine Methode für einen Ausdruck mit dem Wert NULL aufrufen.
Bei D:\permissions\roles.ps1:54 Zeichen:20
+ $node.AppendChild <<<< ($tmp)
+ CategoryInfo : InvalidOperation: (AppendChild:String) [], RuntimeException
+ FullyQualifiedErrorId : InvokeMethodOnNull

I had the same problem. I fixed it by replacing the $global: variables by normal one.

$vInventory.SelectNodes($path) instead of $global:vInventory.SelectNodes($path)

And this with all global variables.