I have the following tiny PowerShell script that's meant to kill some certain processes on a remote machine:
$destPS = "mywebserver1"
$brokerPIDs = Get-Process -ComputerName $destPS | ?{$_.processname -eq "uniRQBroker" -or $_.processname -eq "uniRTE"}
foreach ($process in $brokerPIDs){
$thisId = $process.ID
Write-Host "Killing PID $thisId"
Invoke-Command $destPS {Stop-Process $thisId}
}
However, I'm getting the following error:
Cannot bind argument to parameter 'Id' because it is null.
As far as I can see, the pipeline shouldn't be interrupted by anything, so I'm not quite sure where I'm going wrong.
The script block doesn't get the $thisId and that is set to null. So stop-process gives the error. You can pass the arguments to the script block like #Rynant mentions.
Since all you are doing is to get the processes and kill processes that match your requirement, move the commands into a script block and execute that scriptblock as whole using Invoke-Command on the remote box:
$script = {Get-Process -name uniRQBroker,uniRTE | stop-process -passthru | %{write-host killed pid $_.id}}
invoke-command -script $script -computer $destPS
You need to pass the variable thisId to the scriptblock as an argument (Invoke-Command executes the scriptblock in a separate temporary session when running against a remote computer, hence local variables are no longer in scope). Try it as:
Invoke-Command $destPS {Stop-Process $args} -ArgumentList $thisID
Related
I'm looking for method to create a wrapper around Invoke-Command that restores the current directory that I'm using on the remote machine before invoking my command. Here's what I tried to do:
function nice_invoke {
param(
[string]$Computer,
[scriptblock]$ScriptBlock
)
Set-PSDebug -Trace 0
$cwd = (Get-Location).Path
write-host "cmd: $cwd"
$wrapper = {
$target = $using:cwd
if (-not (Test-Path "$target")) {
write-host "ERROR: Directory doesn't exist on remote"
exit 1
}
else {
Set-Location $target
}
$sb = $using:ScriptBlock
$sb.Invoke() | out-host
}
# Execute Command on remote computer in Same Directory as Local Machine
Invoke-Command -Computer pv3039 -ScriptBlock $wrapper
}
Command Line:
PS> nice_invoke -Computer pv3039 -ScriptBlock {get-location |out-host; get-ChildItem | out-host }
Error Message:
Method invocation failed because [System.String]
does not contain a method named 'Invoke'.
+ CategoryInfo : InvalidOperation: (:) [], RuntimeException
+ FullyQualifiedErrorId : MethodNotFound
+ PSComputerName : pv3039
You can't pass a ScriptBlock like this with the $using: scope, it will get rendered to a string-literal first. Use the [ScriptBlock]::Create(string) method instead within your $wrapper block to create a ScriptBlock from a String:
$sb = [ScriptBlock]::Create($using:ScriptBlock)
$sb.Invoke() | Out-Host
Alternatively, you could also use Invoke-Command -ArgumentList $ScriptBlock, but you still have the same issue with the ScriptBlock getting rendered as a string. Nonetheless, here is an example for this case as well:
# Call `Invoke-Command -ArgumentList $ScriptBlock`
# $args[0] is the first argument passed into the `Invoke-Command` block
$sb = [ScriptBlock]::Create($args[0])
$sb.Invoke() | Out-Host
Note: While I kept the format here in the way you were attempting to run the ScriptBlock in your original code, the idiomatic way to run ScriptBlocks locally (from the perspective the nested ScriptBlock it is a local execution on the remote machine) is to use the Call Operator like & $sb rather than using $sb.Invoke().
With either approach, the nested ScriptBlock will execute for you from the nested block now. This limitation is similar to how some other types are incompatible with shipping across remote connections or will not survive serialization with Export/Import-CliXml; it is simply a limitation of the ScriptBlock type.
Worthy to note, this limitation persists whether using Invoke-Command or another cmdlet that initiates execution via a child PowerShell session such as Start-Job. So the solution will be the same either way.
function nice_invoke {
param(
[string]$Computer,
[scriptblock]$ScriptBlock
)
Set-PSDebug -Trace 0
$cwd = (Get-Location).Path
write-host "cmd: $cwd"
$wrapper = {
$target = $using:cwd
if (-not (Test-Path "$target")) {
write-host "ERROR: Directory doesn't exist on remote"
exit 1
}
else {
Set-Location $using:cwd
}
$sb = [scriptblock]::Create($using:ScriptBlock)
$sb.Invoke()
}
# Execute Command on remote computer in Same Directory as Local Machine
Invoke-Command -Computer pv3039 -ScriptBlock $wrapper
}
nice_invoke -Computer pv3039 -ScriptBlock {
hostname
get-location
#dir
}
New to PowerShell and learning through writing random scripts using the help info. I've tried the following 3 ways to properly get variables into the ScriptBlock(along with way too many small variations to list) with listed error message wrapped in **:
do
{
try {
[ValidateRange(1,7)][int]$days = Read-Host "Let's pull up some Warning event logs. How many days back would you like to go back? (1-7)"
} catch {}
} until ($?)
do
{
try {
[ValidateSet('desktop','documents',IgnoreCase)]$location = Read-Host "Would you like me to save the log on your Desktop or in your Documents?"
} catch {}
} until ($?)
$filename = Read-Host "What would you like to name the file?"
$DaysAgo = [datetime]::Now.AddDays(-$days)
Invoke-Command -AsJob -Jobname JobEventLog -ScriptBlock {Get-EventLog -logname system | Where-Object EntryType -eq Warning | where TimeGenerated -ge $DaysAgo | Out-File $HOME\$location\$filename.txt}
Invoke-Command : Parameter set cannot be resolved using the specified named parameters.
do
{
try {
[ValidateRange(1,7)][int]$days = Read-Host "Let's pull up some Warning event logs. How many days back would you like to go back? (1-7)"
} catch {}
} until ($?)
do
{
try {
[ValidateSet('desktop','documents',IgnoreCase)]$location = Read-Host "Would you like me to save the log on your Desktop or in your Documents?"
} catch {}
} until ($?)
$filename = Read-Host "What would you like to name the file?"
$DaysAgo = [datetime]::Now.AddDays(-$days)
Invoke-Command -AsJob -Jobname JobEventLog -ScriptBlock {Get-EventLog -logname system | Where-Object EntryType -eq Warning | where TimeGenerated -ge $Using:$DaysAgo | Out-File $Using:HOME\$Using:location\$Using:filename.txt}
Invoke-Command : Parameter set cannot be resolved using the specified named parameters.
do
{
try {
[ValidateRange(1,7)][int]$days = Read-Host "Let's pull up some Warning event logs. How many days back would you like to go back? (1-7)"
} catch {}
} until ($?)
do
{
try {
[ValidateSet('desktop','documents',IgnoreCase)]$location = Read-Host "Would you like me to save the log on your Desktop or in your Documents?"
} catch {}
} until ($?)
$filename = Read-Host "What would you like to name the file?"
Write-Host "Processing..."
$DaysAgo = [datetime]::Now.AddDays(-$days)
$parameters = #{
ScriptBlock = { Param ($Arg1,$Arg2,$Arg3) Invoke-Command -AsJob -Jobname JobEventLog -ScriptBlock {Get-EventLog -logname system | Where-Object source -eq DCOM | where TimeGenerated -ge $Arg1 | Out-File "$HOME\$Arg2\$Arg3.txt"}}
JobName = "DCOM"
ArgumentList = ($DaysAgo,$location,$filename)
}
Invoke-Command #parameters
Invoke-Command : Cannot validate argument on parameter 'ScriptBlock'. The argument is null. Provide a valid value for the argument, and then try running the command again.
I'm just looking to have user input how far back they want to view Event Logs, where to save it, and what to name it. I've been able to work my way through everything so far until I hit the Invoke-Command line and haven't been able to get through it. I prefer the one line style of 1 and 2 over the parameters style, however after spending way too much time using the help_Invoke-Command-full and googling I'm throwing in the towel over what I'm sure is a simple error on my syntax.
You can use $args inside the scriptblock, see an example:
$DaysAgo = [datetime]::Now.AddDays(-$days)
Invoke-Command -AsJob -Jobname JobEventLog -ScriptBlock {
Get-EventLog -logname system | Where-Object EntryType -eq Warning |
where TimeGenerated -ge $args[0] |
Out-File $HOME\$location\$filename.txt
} -ArgumentList $DaysAgo
Add the arguments at the end of the Invoke-Command like in the example and use $args[0] for the first argument, $args[1] for the second and so on...
This works for me. The computer is localhost as a test, at an elevated prompt, which you would need for the system log anyway. Level 3 is warning. If it was for the same computer you wouldn't need invoke-command at all.
$location = 'foo'
$filename = 'myfile'
$date = get-date
$daysago = $date.adddays(-1)
invoke-command localhost { param($daysago, $location, $filename)
get-winevent #{logname = 'system'; level = 3; starttime = $daysago} |
out-file $home\$location\$filename.txt } -args $daysago,$location,$filename
In order to use Invoke-Command's -AsJob switch, you must execute code remotely, such as by targeting a different computer with the -ComputerName or -Session arguments.
In the absence of such arguments, your command would run locally, but it fails due to the syntactic restriction described above.
If you want to run a job locally, use Start-Job directly:
$job = Start-Job -Name JobEventLog -ScriptBlock {
Get-EventLog -logname system |
Where-Object EntryType -eq Warning |
Where-Object TimeGenerated -ge $using:DaysAgo |
Out-File $HOME\$using:location\$using:filename.txt
}
Note: Since your background script block references variables from the caller's scope, they must be referenced via the $using: scope (as you've also done in your last Invoke-Command-based attempt). This requirement also applies to script blocks executed remotely, such as via Invoke-Command -ComputerName - see this answer for background information. The alternative is to pass arguments to the script block, via the -ArgumentList (-Args) parameter, though the $using: approach is usually simpler.
Start-Job returns a job-information object (System.Management.Automation.Job), which you can use to monitor the progress of and obtain output from the background job, using the various *-Job cmdlets, notably Wait-Job and Receive-Job - see the about_Jobs conceptual help topic.
Generally, using Invoke-Command for local code execution, while technically supported, is rarely necessary.
For direct, synchronous invocation (not as a job) of a command or script block, use &, the call operator (not needed for single commands, as long as the command name isn't quoted or specified via a variable), or, for execution directly in the caller's scope, ., the dot-sourcing operator (. { ... }).
You have a couple of options. Since you're only running this on your local machine, you can use Start-Job instead of Invoke-Command.
That being said, the problem that you're running into is 2-fold. First, if you're running the Invoke-Command cmdlet, you'll need to specify the ComputerName parameter. Even though it's an optional parameter, you'll need to use it to tell Powershell which parameter set you're using, otherwise it's going to get confused.
Secondly, you'll need to pass the arguments into the scriptblock. This is because Start-Job and Invoke-Command are part of PSRemoting and will actually look for environment variables on the specified computer instead of variables that you've declared in your script.
Here's what worked for me:
Invoke-Command -ComputerName $(hostname) -AsJob -JobName "TestJob" -ScriptBlock { Get-EventLog -logname system | Where-Object EntryType -eq Warning | Where-Object -property TimeGenerated -ge $args[0] | Out-File "$HOME\$($args[1])\$($args[2]).txt" } -ArgumentList $DaysAgo, $location, $filename
The Invoke-Command option is powerful if you're wanting to get this information from other devices on your network.
And here's the Start-Job version:
Start-Job -Name "TestJob2" -ScriptBlock { Get-EventLog -logname system | Where-Object EntryType -eq Warning | Where-Object -property TimeGenerated -ge $args[0] | Out-File "$HOME\$($args[1])\$($args[2]).txt" } -ArgumentList $DaysAgo, $location, $filename
I have a script located on a remote system.
On the server "web12" under C:\tmp\hgttg.ps1:
Write-Host "Don't Panic"
exit 42
I invoke this script from my local box (both systems running v4.0) using Invoke-Command:
$svr = "web12"
$cmd = "C:\tmp\hgttg.ps1"
$result = Invoke-Command -ComputerName $svr -ScriptBlock {& $using:cmd}
This causes the following output when executed:
> $result = Invoke-Command -ComputerName $svr -ScriptBlock {& $using:cmd}
Don't Panic
> $result
>
($result is not set, output goes straight to the console, no good!) After much web searching and troubleshooting, I have come to some improvement:
> $result = Invoke-Command -ComputerName $svr -ScriptBlock {& $using:cmd; $LASTEXITCODE}
Don't Panic
> $result
42
>
Now I'm able to capture the return code, but the output still goes straight to the console. This is as far as I can get. On the long list of things I have already attempted, none of the following have worked:
Instead of '&' used 'Invoke-Expression' with -OutVariable out; New-Object -TypeName PSCustomObject -Property #{code=$LASTEXITCODE; output=$out}
This produces the output:
> $result
code : 42
output :
PSComputerName : web12
RunspaceId : aaa00a00-d1fa-4dd6-123b-aa00a00000000
>
Attempted both iterations above with '4>&1' and '*>&1' on the end of the inner and outer commands, no change.
Attempted each of:
"& $using:cmd | Tee-Object -Variable out; $out"
"& $using:cmd >$out; $out"
"$out = & $using:cmd; $out"
(Discarding the return code just to get output) Again, no change.
Also attempted: '& $using:cmd >> C:\tmp\output.log; $LASTEXITCODE'. The generated file was empty, and the text was still output to the local terminal.
I'm sure there's something obvious that I'm missing, but so far all I've hit are dead ends. Any suggestions?
On PSv4- (versions 4.x or below), you simply cannot capture Write-Host output - it invariably goes straight to the console.
In PSv5+, Write-Host (too) writes to the newly introduced information stream that the newly introduced Write-Information cmdlet is designed to write to; its number is 6.
Thus, if your target host runs PSv5+, you can use the following; note how *> captures all output streams by redirecting (&) them to the success stream (1), but you can use 6> to capture the information stream selectively):
$result = Invoke-Command -ComputerName $svr -ScriptBlock {& $using:cmd *>&1; $LASTEXITCODE}
$output = $result[0..($result.Count-2)]
$exitCode = $result[-1]
Been trying to solve this for a bit and can't seem to figure it out.
I have the following script:
$Servers = Get-Content -Path "C:\Utilities_PowerShell\ServerList.txt"
$IISServiceName1 = 'W3SVC'
$IISServiceName2 = 'IISAdmin'
$IISServiceName3 = 'WAS'
$IISarrService = Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3
$IISarrServiceCheck = Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3 -ErrorAction SilentlyContinue -ErrorVariable NoService
function IISServiceStatus # Checks for status of IIS services
{
param (
$IISServiceName1,
$IISServiceName2,
$IISServiceName3,
$IISarrService,
$IISarrServiceCheck
)
if (Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3)
{
Write-Host "Status of IIS service(s) on $env:ComputerName :"
Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3 | Select Name,DisplayName,Status | Format-Table -AutoSize
}
else
{
Write-Host " No IIS service(s) were found..." -foreground "red"
}
}
$Sessions = New-PSSession -ComputerName $Servers
$EndJobs = $Sessions | ForEach-Object {
Invoke-Command -Session $_ -ScriptBlock ${function:IISServiceStatus} -AsJob -ArgumentList $IISServiceName1, $IISServiceName2, $IISServiceName3, $IISarrService, $IISarrServiceCheck | Wait-Job | Receive-Job
Write-Host " "
}
Whenever I run it, all I get is the output of:
Status of IIS service(s) on *PC* :
If I run the function outside of a loop/invoke-command, the results are absolutely perfect. What is wrong with my remote loop?
I've tried putting the variables inside the function, I've tried running invoke-command without the argument list, etc.
Update: 3/17/16
Turns out...if I run my actual script as is, the result of $EndJobs is weird in that it outputs ALL services in one table and then the three IIS services in another table. This would explain why when I run my invoke-command (stopIIS) scriptblock...I had to reboot the whole server because it took all of the services down.
These functions run PERFECTLY when not run via remote/invoke-command.
What the heck...invoke-command is seriously screwing with my stuff!
Anyone have any ideas/tips on how I can run my local script (which works 100%) on a set of servers from a text file without weird issues like this? Is invoke-command the only way?
do you have the same problem if you wrap it all into the script block like this?
$Servers = Get-Content 'C:\Utilities_PowerShell\ServerList.txt'
$Sessions = New-PSSession -ComputerName $Servers
$EndJobs = $Sessions | ForEach-Object {
Invoke-Command -Session $_ -ScriptBlock {
$IISServiceName1 = 'W3SVC'
$IISServiceName2 = 'IISAdmin'
$IISServiceName3 = 'WAS'
$IISarrService = Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3
$IISarrServiceCheck = Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3 -ErrorAction SilentlyContinue -ErrorVariable NoService
function IISServiceStatus { # Checks for status of IIS services
param (
$IISServiceName1,
$IISServiceName2,
$IISServiceName3,
$IISarrService,
$IISarrServiceCheck
)
if (Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3) {
Write-Host "Status of IIS service(s) on $env:ComputerName :"
Get-Service -Name $IISServiceName1,$IISServiceName2,$IISServiceName3 | Select Name,DisplayName,Status | Format-Table -AutoSize
} else {
Write-Host ' No IIS service(s) were found...' -ForegroundColor Red
}
}
IISServiceStatus $IISServiceName1 $IISServiceName2 $IISServiceName3 $IISarrService $IISarrServiceCheck
} -AsJob | Wait-Job | Receive-Job
Write-Host ' '
}
$EndJobs
I'm having a similar issue. I'm using credssp to test 2nd hop auth for an automation for shutting down a production environment cleanly. My script has 3 sections; session setup, the invoke, session teardown. If I run each piece separately, I get output. If I run the whole script, I get blank lines matching the amount of output I get when I run them separately... there's nothing fancy in my invoke (backtick line continuation - I prefer Python's formatting paradigm better than Powershell/C#):
Invoke-Command `
-Session $workingSession `
-ScriptBlock {
get-service *spool* -ComputerName server01
}
My question is very similar to this one, except I'm trying to capture the return code of a ScriptBlock using Invoke-Command (so I can't use the -FilePath option). Here's my code:
Invoke-Command -computername $server {\\fileserver\script.cmd $args} -ArgumentList $args
exit $LASTEXITCODE
The problem is that Invoke-Command doesn't capture the return code of script.cmd, so I have no way of knowing if it failed or not. I need to be able to know if script.cmd failed.
I tried using a New-PSSession as well (which lets me see script.cmd's return code on the remote server) but I can't find any way to pass it back to my calling Powershell script to actually DO anything about the failure.
$remotesession = new-pssession -computername localhost
invoke-command -ScriptBlock { cmd /c exit 2} -Session $remotesession
$remotelastexitcode = invoke-command -ScriptBlock { $lastexitcode} -Session $remotesession
$remotelastexitcode # will return 2 in this example
Create a new session using new-pssession
Invoke your scripblock in this session
Fetch the lastexitcode from this session
$script = {
# Call exe and combine all output streams so nothing is missed
$output = ping badhostname *>&1
# Save lastexitcode right after call to exe completes
$exitCode = $LASTEXITCODE
# Return the output and the exitcode using a hashtable
New-Object -TypeName PSCustomObject -Property #{Host=$env:computername; Output=$output; ExitCode=$exitCode}
}
# Capture the results from the remote computers
$results = Invoke-Command -ComputerName host1, host2 -ScriptBlock $script
$results | select Host, Output, ExitCode | Format-List
Host : HOST1
Output : Ping request could not find host badhostname. Please check the name and try again
ExitCode : 1
Host : HOST2
Output : Ping request could not find host badhostname. Please check the name and try again.
ExitCode : 1
I have been using another method lately to solve this problem. The various outputs that come from the script running on the remote computer are an array.
$result = Invoke-Command -ComputerName SERVER01 -ScriptBlock {
ping BADHOSTNAME
$lastexitcode
}
exit $result | Select-Object -Last 1
The $result variable will contain an array of the ping output message and the $lastexitcode. If the exit code from the remote script is output last then it can be fetched from the complete result without parsing.
To get the rest of the output before the exit code it's just:
$result | Select-Object -First $(result.Count-1)
#jon Z's answer is good, but this is simpler:
$remotelastexitcode = invoke-command -computername localhost -ScriptBlock {
cmd /c exit 2; $lastexitcode}
Of course if your command produces output you'll have to suppress it or parse it to get the exit code, in which case #jon Z's answer may be better.
It is better to use return instead of exit.
For example:
$result = Invoke-Command -ComputerName SERVER01 -ScriptBlock {
return "SERVER01"
}
$result