[SOLVED] Powershell leaving RemoteDrive Sessions open

Powershell leaving RemoteDrive Sessions open

Minimal Question:

How do I properly dispose of the remote Session Connection left behind after doing:

$session = New-PSSession -ComputerName $VM -Credential $CurrentUser
Invoke-Command -Session $session -ScriptBlock {
    $drive = New-PSDrive -Credential $Using:CurrentUser "dummyDriveName" -Root (Split-Path $Using:TargetPath) -PSProvider "FileSystem" 
    Set-Location $Using:TargetPath
}

Invoke-Command -Session $session -ScriptBlock {
    Remove-PSDrive "dummyDriveName"
}
Remove-PSSession -Session $session

I'm running code that looks roughly like this:

$VMs = @(
    "vm1.foo.lan",
    "vm2.foo.lan",
    "vm3.foo.lan"
)

$TargetPath = "\\$env:ComputerName\bar\bin\Debug"

$CurrentUser = (Get-Credential -Credential $env:UserName)
[System.Management.Automation.Runspaces.PSSession[]]$Sessions = @()

foreach ($VM in $VMs) {
    $session = New-PSSession -ComputerName $VM -Credential $CurrentUser
    $Sessions = $Sessions + $session

    Invoke-Command -Session $session -ScriptBlock {
        $drive = New-PSDrive -Credential $Using:CurrentUser "dummyDriveName" -Root (Split-Path $Using:TargetPath) -PSProvider "FileSystem" 
        Set-Location $Using:TargetPath
        #Actually do something here, but it's not relevant ... I can reproduce with this line commented out.
    }
}

# Wait until Target.exe are known to be complete.

foreach ($session in $Sessions) {
    Invoke-Command -Session $session -ScriptBlock {
        Remove-PSDrive "dummyDriveName"
    }
    Remove-PSSession -Session $session
}

My intent is to get a set of remote machines to all invoke an exe sitting on my machine, exposed via a remote share.

Broadly speaking, I:

Connect to the remote machine as myself.
Capture that connection.
Set up a remote drive connecting it to me
- (This is REQUIRED to avoid the double hop issue without resorting to CredSsp See: https://learn.microsoft.com/en-us/powershell/scripting/setup/ps-remoting-second-hop)
Do some stuff
Repeat for all machines.
Wait until remote processes are completed.
Reconnect to all the machines to remove the drive and the connection session.

At the end of this, I still have:

These sessions do eventually seem to decay, but not reliably, and it's been able to saturate the max # sessions allowed and thus cause errors saying:

No more connections can be made to this remote computer at this time because there are already as many connections as the computer can accept
+ CategoryInfo          : InvalidOperation: (dummy:PSDriveInfo) [New-PSDrive], Win32Exception
+ FullyQualifiedErrorId : CouldNotMapNetworkDrive,Microsoft.PowerShell.Commands.NewPSDriveCommand
+ PSComputerName        : build7.foo.lan

UPDATE:

Thanks to @jrider who has suggested Get-SmbSession. Running that after the rest of my script returns:

PS C:\WorkingDirectoty> Get-SmbSession

SessionId    ClientComputerName ClientUserName NumOpens
---------    ------------------ -------------- --------
773228331225 10.xxx.yyy.89       FOO\MDM        785
773228331233 10.xxx.yyy.60       FOO\MDM        637
773228331245 10.xxx.yyy.89       FOO\MDM        239
773228331253 10.xxx.yyy.54       FOO\MDM        136
773228331261 10.xxx.yyy.54       FOO\MDM        882
773228331269 10.xxx.yyy.60       FOO\MDM        389

I obviously don't want this script to blindly close EVERY session irrespective of whether it relates to this script, so I guess I want to map my sessions to IP addresses and close anything with that IP address? Does anyone JustKnow the necessary PowerShell incantation to achieve that?

Solution

To Close the SMB sessions by computer name(Updated to include Brondahl's suggestion):

$vmName = $env:ComputerName
$IP =  [System.Net.Dns]::GetHostAddresses($vmName).IPAddressToString
Get-SmbSession | Where-Object {$_.ClientComputerName -eq $IP} | Close-SmbSession -Force