How to log into remote servers? - powershell

Question

I currently have a VBScript that reads a list of servers, and attempts to verify the password of a specific userid. The userid is locally on that server. I am checking to see that the password is not set to the default (I want to make sure it was changed to something else).
The "list of servers" can be a mix of IP addresses, hostnames (like Rocky), or fully qualified DNS names (like rocky.bigcompany.com). The servers are a mixture of physical and virtual devices, and may or may not be on a domain.
The existing VBScript I wrote handles all this, and works fine. I'm trying to re-write this same program in Powershell, and It's not working.
Here's the function I have in VBScript that does what I want:
Function LoginToServer(Computer, username, password)
'this function will log into a server
On Error Resume next
Set locator = CreateObject("WbemScripting.SWbemLocator")
Set wmi = locator.ConnectServer(computer, "root\cimv2", username, password)
'check the error code and see if we logged in successfully
LoginRC = Err.Number
If LoginRC <> 0 Then
msg = "Could not log into server: " & CStr(computer) & " With ID: " & CStr(username)
lfo.lmsg "B", "WARN", msg
Else
msg = "Server: " & CStr(computer) & " Logged in successfully as: " & CStr(username)
lfo.lmsg "B", "INFO", msg
End If
wmi.Security_.ImpersonationLevel = 3
'return the code back to calleer
LoginToServer = LoginRC
End Function
… and here's what I've tried to do in PowerShell:
Param($ComputerName = "LocalHost")
$ErrorActionPreference = "Stop"
# Actual Code starts here
Write-Host "Attempting to ping server: $ComputerName"
$IPResult = Test-Connection -ComputerName $ComputerName -Quiet
if ($IPResult -eq "TRUE") {
Write-Host "Ping OK - now attempting to log in"
try {
$ID = "userid"
$PSW = "password"
$password = ConvertTo-SecureString $PSW -AsPlainText -Force
$cred = New-Object System.Management.Automation.PSCredential ($ID, $password)
$sesh = New-PSSession -ComputerName $ComputerName -Credential $cred
} catch {
Write-Host "Error caught"
$ErrorMessage = $_.Exception.Message
$FailedItem = $_.Exception.ItemName
} finally {
$Time = Get-Date
"$Time Computer: $ComputerName ERROR: $ErrorMessage ITEM: $FailedItem" |
Out-File c:\temp\TestCredScript.log -Append
}
} else {
Write-Host "Could not ping server"
}
How do I log into these remote computers with an ID and Password using PowerShell?

Answer 1

Your two code samples do different things. The VBScript code connects via WMI whereas the PowerShell code tries to establish a PowerShell session. For the latter you need PowerShell Remoting enabled, which you probably don't have.
While you probably may want to enable PSRemoting anyway, you can also use WMI from PowerShell. The Get-WmiObject cmdlet allows you to provide credentials and impersonation level, so you don't need to establish a connection first like you need to do with VBScript (if you want to use explicit credentials).
Example querying the Win32_Process class on a remote computer:
$computer = '...'
$username = 'userid'
$password = 'password'
$pw = ConvertTo-SecureString $password -AsPlainText -Force
$cred = New-Object Management.Automation.PSCredential ($username, $pw)
Get-WmiObject -Computer $computer -Namespace 'root\cimv2' -Class Win32_Process -Impersonation 3 -Credential $cred
See here for further information.