Question

Does anyone know how I can load a DLL without having it on each remote server I am using in a persistent connection and running the invoke-command cmdlet with?

I am using DotNetZip to backup folders on about 13 servers. Everything is working locally, but when it gets to a remote server (the first one in the array is the local server), it errors because it doesn’t see the DLL on the remote server.

I execute this script on one server and it should zip up folders on each remote server:

foreach($i in $appServers) {
        $sessionForI = New-PSSession -computername $i
        Invoke-Command -Session $sessionForI -ScriptBlock {
            if (!(Test-Path -path C:\\newDeploy)) {
                New-Item C:\\newDeploy -type directory
            }
            [System.Reflection.Assembly]::LoadFrom("C:\\newDeploy\\Ionic.Zip.dll");
            $directoryToZip = "C:\\Program Files (x86)\\SubDir\\$folder"
            $zipfile = new-object Ionic.Zip.ZipFile
            $e = $zipfile.AddSelectedFiles("name != '*.e2e'",$directoryToZip, "",1)
            if (!(Test-Path -path C:\\newDeploy\\backup)) {
                New-Item C:\\newDeploy\\backup -type directory
            }
            $zipfile.Save("C:\\newDeploy\\backup\\" + $folder+ ".zip")
            $zipfile.Dispose()
        }
        remove-PSSession -session $sessionForI
    }

Thank you .

-Jim

Answer 1

I’m pretty sure you are going to need to copy Ionic.Zip.dll to the remote machines to do this. You could try sharing it out from your lead system and using a UNC path to load it from the remote machines (i’ve never tried that… going to now…) 🙂

Update – yep just confirmed you can pass a UNC path to [System.Reflection.Assembly]::LoadFrom.

Update 2 – While the assembly loaded, using it didn’t work so well:

Exception calling "AddFile" with "1" argument(s): "Request for the permission of type 'System.Security.Permissions.File
IOPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed."
At line:1 char:11
+ $z.AddFile <<<< ("C:\AMCleanUp.log")
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : DotNetMethodException

When I loaded a local copy of the the DLL the AddFile method worked fine. You’re only option might be to copy this DLL to all your servers…