OK, i am trying to get this script to work and not continuously hit the same computers over and over and am having trouble getting it working. I don't think this is the best way to do it and if you have any suggestions please and thank you. Anyways there seems to be an issue with line 6 "IF (!$Succssful.Contains($Computer)) {" it doesn't shoot an error at me but instead ends the script per-maturealy. I have tried removing the "!" but no luck as I expected.
$Computers = "TrinityTechCorp"
$HotFixes = Get-Content HotFixes.csv
While ($Successful -AND $Successful.count -ne $Computers.count) {
ForEach ($Computer in $Computers) {
IF (!$Succssful.Contains($Computer)) {
If (Test-Connection $Computer) {
$Comparison = get-hotfix -ComputerName $Computer | Select -expand HotFixID
ForEach ($HotFix in $HotFixes) {
IF ($Comparison -NotLike "*$HotFix*") {
Write-Host "$Computer missing $HotFix"
}
$Successful += $Computer
}
}
}
}
}
This line
While ($Successful -AND $Successful.count -ne $Computers.count) {
can never evaluate to $true. The .count-property of a non-existing variable ($Successful) is $null, and the same goes for a string (because you specify only 1 computer, it's not an array).
To force Powershell to return the "true" number of items, use #($Successful).count and #($Computers).count instead. This will give you 1, even if $Computers wasn't defined as an array. So, with variables substituted, your line is interpreted as
While ($null -AND $null.count -ne $null) {
In Powershell 3, as you can read here, this is no longer the case.
Related
I am trying to modify a variable within Invoke-Command in order to get out of a loop, however I'm having trouble doing that.
In the sample script below, I'm connecting to a host, grabbing information from NICs that are Up and saving the output to a file (Baseline). Then on my next iteration I will keep grabbing the same info and then compare Test file to Baseline file.
From a different shell, I've connected to the same server and disabled one of the NICs to force Compare-Object to find a difference.
Once a difference is found, I need to get out of the loop, however I cannot find a way to update the local variable $test_condition. I've tried multiple things, from Break, Return, $variable:global, $variable:script, but nothing worked so far.
$hostname = "server1"
$test_condition = $false
do {
Invoke-Command -ComputerName $hostname -Credential $credential -ScriptBlock{
$path = Test-Path -LiteralPath C:\Temp\"network_list_$using:hostname-Baseline.txt"
if ($path -eq $false) {
Get-NetAdapter | Where-Object Status -EQ "Up" | Out-File -FilePath (New-Item C:\Temp\"network_list_$using:hostname-Baseline.txt" -Force)
} else {
Get-NetAdapter | Where-Object Status -EQ "Up" | Out-File -FilePath C:\Temp\"network_list_$using:hostname-Test.txt"
$objects = #{
ReferenceObject = (Get-Content C:\Temp\"network_list_$using:hostname-Baseline.txt")
DifferenceObject = (Get-Content C:\Temp\"network_list_$using:hostname-Test.txt")
}
$test_condition = (Compare-Object #objects).SideIndicator -ccontains "<="
$test_condition #this is returning True <-----
}
}
} until ($test_condition -eq $true)
Any tips? What am I doing wrong?
TIA,
ftex
You can pass variables into a remote script block with the $Using:VarName scope modifier, but you can't use typical $Global: or $Script to modify anything in the calling scope. In this scenario the calling scope isn't the parent scope. The code is technically running in a new session on the remote system and $Global: would refer to that session's global scope.
For example:
$var = "something"
Invoke-Command -ComputerName MyComuter -ScriptBlock { $Global:var = "else"; $var}
The remote session will output "else". However, after return in the calling session $var will output "something" remaining unchanged despite the assignment in the remote session.
Based on #SantiagoSquarzon's comment place the assignment inside the Do loop with a few other modifications:
$hostname = "server1"
do {
$test_condition = $false
$test_condition =
Invoke-Command -ComputerName $hostname -Credential $credential -ScriptBlock{
$path = Test-Path -LiteralPath C:\Temp\"network_list_$using:hostname-Baseline.txt"
if ($path -eq $false) {
Get-NetAdapter | Where-Object Status -eq "Up" | Out-File -FilePath (New-Item C:\Temp\"network_list_$using:hostname-Baseline.txt" -Force)
} else {
Get-NetAdapter | Where-Object Status -eq "Up" | Out-File -FilePath C:\Temp\"network_list_$using:hostname-Test.txt"
$objects = #{
ReferenceObject = (Get-Content C:\Temp\"network_list_$using:hostname-Baseline.txt")
DifferenceObject = (Get-Content C:\Temp\"network_list_$using:hostname-Test.txt")
}
(Compare-Object #objects).SideIndicator -contains "<=" # this is returning True <-----
}
}
} until ($test_condition -eq $true)
I don't know why you were using -ccontains considering "<=" has no casing implications. Also it's very unusual to capitalize operators.
Notice there's no explicit return or assignment. PowerShell will emit the Boolean result of the comparison and that will be returned from the remote session and end up assigned to the $test_condition variable.
An aside:
I'm not sure why we want to use -contains at all. Admittedly it'll work fine in this case, however, it may lead you astray elsewhere. -contains is a collection containment operator and not really meant for testing the presence of one string within another. The literal meaning of "contains" makes for an implicitly attractive hazard, as demonstrated in this recent question.
In short it's easy to confuse the meaning, purpose and behavior on -contains.
This "<=" -contains "<=" will return "true" as expected, however "<==" -contains "<=" will return "false" even though the left string literally does contain the right string.
The answer, to the aforementioned question says much the same. My addendum answer offers a some additional insight for the particular problem and how different operators can be circumstantially applied.
So, as a matter of practice for this case wrap the Compare-Object command in the array sub-expression operator like:
#( (Compare-Object #objects).SideIndicator ) -contains "<="
Given the particulars, this strikes me as the least intrusive way to implement such a loosely stated best practice.
I found this thread that offers two basic approaches to getting local group members.
This works for me in all versions of powershell, but depends on using the old NET command line utility.
function Get-LocalGroupMembers() {
param ([string]$groupName = $(throw "Need a name") )
$lines = net localgroup $groupName
$found = $false
for ($i = 0; $i -lt $lines.Length; $i++ ) {
if ( $found ) {
if ( -not $lines[$i].StartsWith("The command completed")) {
$lines[$i]
}
} elseif ( $lines[$i] -match "^----" ) {
$found = $true;
}
}
}
This works for me in PowerShell 2.0, but barfs in PS5.0 with Error while invoking GetType. Could not find member.
It only barfs on some groups, including Administrators, which has me thinking it's some sort of security feature, like requiring elevated privileges to REALLY have admin rights in a script.
Function Get-LocalGroupMembers
{
Param(
[string]
$server = "."
)
Try
{
$computer = [ADSI]"WinNT://$( $Server ),computer"
$computer.psbase.children |
where {
$_.psbase.schemaClassName -eq 'group'
} |
ForEach {
$GroupName = $_.Name.ToString()
$group =[ADSI]$_.psbase.Path
$group.psbase.Invoke("Members") |
foreach {
$memberName = $_.GetType().InvokeMember("Name", 'GetProperty', $null, $_, $null) -replace "WinNT:", ""
$props = #{
"LocalGroup" = $GroupName
"MemberName" = $memberName
}
$obj = New-Object -TypeName psobject -Property $props
Write-Output $obj
} # foreach members
} # foreach group
}
Catch
{
Throw
}
}
I think I read somewhere that PS5.1 has a native CMDlet finally. But I can't depend on a particular version of PS, I need to support everything from PS2.0 in Win7 up. That said, is there a single version agnostic solution that doesn't depend on a command line utility kludge? Or do I need to have code that uses the old hack or the new CMDlet depending on PS version I am running on?
So, I am having good luck with this solution.
$hostname = (Get-WmiObject -computerName:'.' -class:Win32_ComputerSystem).name
$wmiQuery = Get-WmiObject -computerName:'.' -query:"SELECT * FROM Win32_GroupUser WHERE GroupComponent=`"Win32_Group.Domain='$Hostname',Name='$group'`""
if ($wmiQuery -ne $null) {
:searchLoop foreach ($item in $wmiQuery) {
if (((($item.PartComponent -split "\,")[1] -split "=")[1]).trim('"') -eq $user) {
$localGroup = $true
break :searchLoop
}
}
}
I'm not sure yet if I like that overly complex IF vs some variables, but the functionality is there and working across all versions of PS without resorting to command line kludges, which was the goal.
Note that this just returns true if the user is a member of the group, which is all I need. The other code I posted would provide a list of members, which is the basis of doing a check, and I just hadn't modified it to show the real end goal, since the problem manifested without that.
Instead this :
$memberName = $_.GetType().InvokeMember("Name", 'GetProperty', $null, $_, $null) -replace "WinNT:", ""
You can try this :
$memberName = ([ADSI]$_).InvokeGet("Name")
Essentially I have an If statement that has two conditions using -and, which a string is then run through. However, what I really want is the string to be run through the first condition, then if that is true, it checks for the second, and if that is true it does one thing, and if it is false do something else.
I currently have:
if(($_ -match "/cls") -and ($env:UserName -eq $Name)){cls}
I know I can do what I want with:
if(($_ -match "/cls") -and ($env:UserName -eq $Name)){cls}
elseif(($_ -match "/cls") -and ($env:UserName -ne $Name)){OTHER COMMAND}
But I would like to know if there was a more simple way.
(The result is already being piped in from somewhere else, hence the $_)
Move the first match to the outer scope.
if($_ -match "/cls")
{
if ($env:UserName -eq $Name))
{
cls
}
else
{
other command
}
}
I would write two if statements to improve readabilty. This way, you also need the pipeline value only once::
if($_ -match "/cls")
{
if ($env:UserName -eq $Name)
{
cls
}
else
{
#OTHER COMMAND
}
}
I'm facing the problem of moving and copying some items on the file system with PowerShell.
I know by experiments the fact that, even with PowerShell v3, the cmdlet Copy-Item, Move-Item and Delete-Item cannot handle correctly reparse point like junction and symbolic link, and can lead to disasters if used with switch -Recurse.
I want to prevent this evenience. I have to handle two or more folder each run, so I was thinking to something like this.
$Strings = #{ ... }
$ori = Get-ChildItem $OriginPath -Recurse
$dri = Get-ChildItem $DestinationPath -Recurse
$items = ($ori + $dri) | where { $_.Attributes -match 'ReparsePoint' }
if ($items.Length -gt 0)
{
Write-Verbose ($Strings.LogExistingReparsePoint -f $items.Length)
$items | foreach { Write-Verbose " $($_.FullName)" }
throw ($Strings.ErrorExistingReparsePoint -f $items.Length)
}
This doen't work because $ori and $dri can be also single items and not arrays: the op-Addition will fail. Changing to
$items = #(#($ori) + #($dri)) | where { $_.Attributes -match 'ReparsePoint' }
poses another problem because $ori and $dri can also be $null and I can end with an array containing $null. When piping the join resutl to Where-Object, again, I can end with a $null, a single item, or an array.
The only apparently working solution is the more complex code following
$items = $()
if ($ori -ne $null) { $items += #($ori) }
if ($dri -ne $null) { $items += #($dri) }
$items = $items | where { $_.Attributes -match 'ReparsePoint' }
if ($items -ne $null)
{
Write-Verbose ($Strings.LogExistingReparsePoint -f #($items).Length)
$items | foreach { Write-Verbose " $($_.FullName)" }
throw ($Strings.ErrorExistingReparsePoint -f #($items).Length)
}
There is some better approch?
I'm interested for sure if there is a way to handle reparse point with PowerShell cmdlets in the correct way, but I'm much more interested to know how to join and filters two or more "PowerShell collections".
I conclude observing that, at present, this feature of PowerShell, the "polymorphic array", doen't appear such a benefit to me.
Thanks for reading.
Just add a filter to throw out nulls. You're on the right track.
$items = #(#($ori) + #($dri)) | ? { $_ -ne $null }
I've been on Powershell 3 for a while now but from what I can tell this should work in 2.0 as well:
$items = #($ori, $dri) | %{ $_ } | ? { $_.Attributes -match 'ReparsePoint' }
Basically %{ $_ } is a foreach loop that unrolls the inner arrays by iterating over them and passing each inner element ($_) down the pipeline. Nulls will automatically be excluded from the pipeline.
Is it possible to pull two variables into a Foreach loop?
The following is coded for the PowerShell ASP. The syntax is incorrect on my Foreach loop, but you should be able to decipher the logic I'm attempting to make.
$list = Get-QADUser $userid -includeAllProperties | Select-Object -expandproperty name
$userList = Get-QADUser $userid -includeAllProperties | Select-Object -expandproperty LogonName
if ($list.Count -ge 2)
{
Write-host "Please select the appropriate user.<br>"
Foreach ($a in $list & $b in $userList)
{
Write-host "<a href=default.ps1x?UserID=$b&domain=$domain>$b - $a</a><br>"}
}
}
Christian's answer is what you should do in your situation. There is no need to get the two lists. Remember one thing in PowerShell - operate with the objects till the last step. Don't try to get their properties, etc. until the point where you actually use them.
But, for the general case, when you do have two lists and want to have a Foreach over the two:
You can either do what the Foreach does yourself:
$a = 1, 2, 3
$b = "one", "two", "three"
$ae = $a.getenumerator()
$be = $b.getenumerator()
while ($ae.MoveNext() -and $be.MoveNext()) {
Write-Host $ae.current $be.current
}
Or use a normal for loop with $a.length, etc.
Try like the following. You don't need two variables at all:
$list = Get-QADUser $userid -includeAllProperties
if ($list.Count -ge 2)
{
Write-Host "Please select the appropriate user.<br>"
Foreach ($a in $list)
{
Write-Host "<a href=default.ps1x?UserID=$a.LogonName&domain=$domain>$a.logonname - $a.name</a><br>"
}
}