I have script that stop and start windows services. Currently, it is working fine thru foreach loop; however, it is time consuming. I'm looking for a way to trigger all at the same time instead of go thru $computer object foreach loop and execute 1 by 1. Please advise. Great appreciate
Foreach ($v in $computers)
{
if ($v.value -eq "true")
{
$computers = $v.Name.Split("_")
Write-Host "Processing " $computers[1]
StartOrStopService $computers[1] $StartOrStopService.ToLower()
}
}
Best Regards,
I would suggest using jobs to get the execution go through in parallel
Foreach ($v in $computers)
{
Invoke-Command -ComputerName . -ScriptBlock {
Param($v, $StartOrStopService)
if ($v.value -eq "true")
{
$computers = $v.Name.Split("_")
Write-Host "Processing " $v.Name
StartOrStopService $v.Name $StartOrStopService.ToLower()
}
} -AsJob -ArgumentList $v, $startorStopService
}
You can use Get-Job | Receive-Job if you wanted to see the output of the commands.
Related
I have developed a script which does a lot of processing for a front end tool, now I am attempting to have the script run with multiple threads. It interacts a lot with SQL databases, this should not be a problem for multithreading as the database transactions are very short lived, and the queries well optimised.
what is the issue ?
#.\tester.ps1 -servers (1,'Server1',3,1),(2,'Server2',3,1) -output_folder 'C:\temp'
param ([array[]]$servers),$output_folder
for ($i = 0; $i -lt $servers.Count; $i++)
{
$myserverid = $servers[$i][0]
$myservername = $servers[$i][1]
$mylocationid = $servers[$i][2]
$myappid = $servers[$i][3]
write-output " $myserverid and $myservername and $mylocationid and $myappid"
invoke-sqlcmd -ServerInstance "$myservername" -query "select top 10 name from sysobjects" -Database "master"
}
The script file above will gets passed an array of servers and currently it will loop through the array one by one. A way for me to make the process faster is to run the script in parallel /run the script with multiple threads.
Research
I have looked at a technet script on https://gallery.technet.microsoft.com/scriptcenter/Run-a-PowerShell-script-991c8a42
Its not quite the same as my array is not just a list of servers, there will be other parameters sent with it.
What am I after
A way or pointer to make the script be able to run in parallel or an example using the provided script above.
Thanks in advance.
Extending my comment. In PowerShell v5, use Jobs and Workflows for Parallel use cases.
# Example using parallel jobs
$start = Get-Date
# get all hotfixes
$task1 = { Get-Hotfix }
# get all scripts in your profile
$task2 = { Get-Service | Where-Object Status -eq Running }
# parse log file
$task3 = { Get-Content -Path $env:windir\windowsupdate.log | Where-Object { $_ -like '*successfully installed*' } }
# run 2 tasks in the background, and 1 in the foreground task
$job1 = Start-Job -ScriptBlock $task1
$job2 = Start-Job -ScriptBlock $task2
$result3 = Invoke-Command -ScriptBlock $task3
# wait for the remaining tasks to complete (if not done yet)
$null = Wait-Job -Job $job1, $job2
# now they are done, get the results
$result1 = Receive-Job -Job $job1
$result2 = Receive-Job -Job $job2
# discard the jobs
Remove-Job -Job $job1, $job2
$end = Get-Date
# Example, using WorkFlow
workflow Test-WFConnection
{
param
(
[string[]]$Computers
)
foreach -parallel ($computer in $computers)
{
Test-Connection -ComputerName $computer -Count 1 -ErrorAction SilentlyContinue
}
}
i have two loops in my program.First loop for setting up the retry peocess and inner loop for testing a connection status.
for($retry=0;$retry<=3;$retry++)
{
while (!(Test-Connection "mycomputer"))
{
if (time exceed)
{
$status=$false
Write-Host "machine is offline"
break
}
}
if($status)
{
Write-Host "machine is online"
break
}
}
is there any way to eliminate the inner loop without changing the output
Not entirely sure what you mean by "time exceeded" - time to do what?
If you want to wait between Test-Connection attempts, you can introduce an artificial delay with Start-Sleep:
$Computer = "mycomputer"
$TimeoutSeconds = 5
for($retry=0; $retry -lt 3; $retry++)
{
if(Test-Connection -ComputerName $Computer -Count 1 -Quiet){
# Didn't work
Write-Host "Machine is offline"
# Let's wait a few seconds before retry
Start-Sleep -Seconds $TimeoutSeconds
} else {
Write-Host "Machine is online!"
break
}
}
The easiest way however, would be to use the Count and Delay parameters of Test-Connection:
$Status = Test-Connection -ComputerName $Computer -Count 3 -Delay $TimeoutSeconds
You don't have to use a loop as test-connection already have a count parameter
The other answers already go in depth about why you don't really need a loop but I wanted to add a solution to your refactoring question.
You can eliminate the inner loop and if statement by pre-initializing a $Result variable and changing it in your original loop if necessary.
Personally, I find this more readable (subjective) at the expense of an extra assignment up front.
$Result = "machine is online";
for($retry=0;$retry<=3;$retry++) {
while (!(Test-Connection "mycomputer"))
{
if (time exceed)
{
$Result = "machine is offline"
break
}
}
Write-Host $Result
Edit To test for multiple computers in parallel, I use following worflow
workflow Test-WFConnection {
param(
[string[]]$computers
)
foreach -parallel ($computer in $computers) {
Test-Connection -ComputerName $computer -Count 1 -ErrorAction SilentlyContinue
}
}
called as Test-WFConnection #("pc1", "pc2", ... , "pcn")
Not much of a difference when every computer is online but a world of difference when multiple computers are offline.
Overview
Looking to call a Powershell script that takes in an argument, runs each job in the background, and shows me the verbose output.
Problem I am running into
The script appears to run, but I want to verify this for sure by streaming the results of the background jobs as they are running.
Code
###StartServerUpdates.ps1 Script###
#get list of servers to update from text file and store in array
$servers=get-content c:\serverstoupdate.txt
#run all jobs, using multi-threading, in background
ForEach($server in $servers){
Start-Job -FilePath c:\cefcu_it\psscripts\PSPatch.ps1 -ArgumentList $server
}
#Wait for all jobs
Get-Job | Wait-Job
#Get all job results
Get-Job | Receive-Job
What I am currently seeing:
Id Name State HasMoreData Location Command
-- ---- ----- ----------- -------- -------
23 Job23 Running True localhost #patch server ...
25 Job25 Running True localhost #patch server ...
What I want to see:
Searching for approved updates ...
Update Found: Security Update for Windows Server 2003 (KB2807986)
Update Found: Windows Malicious Software Removal Tool - March 2013 (KB890830)
Download complete. Installing updates ...
The system must be rebooted to complete installation.
cscript exited on "myServer" with error code 3.
Reboot required...
Waiting for server to reboot (35)
Searching for approved updates ...
There are no updates to install.
cscript exited on "myServer" with error code 2.
Servername "myServer" is fully patched after 2 loops
I want to be able to see the output or store that somewhere so I can refer back to be sure the script ran and see which servers rebooted, etc.
Conclusion:
In the past, I ran the script and it went through updating the servers one at a time and gave me the output I wanted, but when I started doing more servers - this task took too long, which is why I am trying to use background jobs with "Start-Job".
Can anyone help me figure this out, please?
You may take a look at the module SplitPipeline.
It it specifically designed for such tasks. The working demo code is:
# import the module (not necessary in PS V3)
Import-Module SplitPipeline
# some servers (from 1 to 10 for the test)
$servers = 1..10
# process servers by parallel pipelines and output results immediately
$servers | Split-Pipeline {process{"processing server $_"; sleep 1}} -Load 1, 1
For your task replace "processing server $_"; sleep 1 (simulates a slow job) with a call to your script and use the variable $_ as input, the current server.
If each job is not processor intensive then increase the parameter Count (the default is processor count) in order to improve performance.
Not a new question but I feel it is missing an answer including Powershell using workflows and its parallel possibilities, from powershell version 3. Which is less code and maybe more understandable than starting and waiting for jobs, which of course works good as well.
I have two files: TheScript.ps1 which coordinates the servers and BackgroundJob.ps1 which does some kind of check. They need to be in the same directory.
The Write-Output in the background job file writes to the same stream you see when starting TheScript.ps1.
TheScript.ps1:
workflow parallelCheckServer {
param ($Servers)
foreach -parallel($Server in $Servers)
{
Invoke-Expression -Command ".\BackgroundJob.ps1 -Server $Server"
}
}
parallelCheckServer -Servers #("host1.com", "host2.com", "host3.com")
Write-Output "Done with all servers."
BackgroundJob.ps1 (for example):
param (
[Parameter(Mandatory=$true)] [string] $server
)
Write-Host "[$server]`t Processing server $server"
Start-Sleep -Seconds 5
So when starting the TheScript.ps1 it will write "Processing server" 3 times but it will not wait for 15 seconds but instead 5 because they are run in parallel.
[host3.com] Processing server host3.com
[host2.com] Processing server host2.com
[host1.com] Processing server host1.com
Done with all servers.
In your ForEach loop you'll want to grab the output generated by the Jobs already running.
Example Not Tested
$sb = {
"Starting Job on $($args[0])"
#Do something
"$($args[0]) => Do something completed successfully"
"$($args[0]) => Now for something completely different"
"Ending Job on $($args[0])"
}
Foreach($computer in $computers){
Start-Job -ScriptBlock $sb -Args $computer | Out-Null
Get-Job | Receive-Job
}
Now if you do this all your results will be mixed. You might want to put a stamp on your verbose output to tell which output came from.
Or
Foreach($computer in $computers){
Start-Job -ScriptBlock $sb -Args $computer | Out-Null
Get-Job | ? {$_.State -eq 'Complete' -and $_.HasMoreData} | % {Receive-Job $_}
}
while((Get-Job -State Running).count){
Get-Job | ? {$_.State -eq 'Complete' -and $_.HasMoreData} | % {Receive-Job $_}
start-sleep -seconds 1
}
It will show all the output as soon as a job is finished. Without being mixed up.
If you're wanting to multiple jobs in-progress, you'll probably want to massage the output to help keep what output goes with which job straight on the console.
$BGList = 'Black','Green','DarkBlue','DarkCyan','Red','DarkGreen'
$JobHash = #{};$ColorHash = #{};$i=0
ForEach($server in $servers)
{
Start-Job -FilePath c:\cefcu_it\psscripts\PSPatch.ps1 -ArgumentList $server |
foreach {
$ColorHash[$_.ID] = $BGList[$i++]
$JobHash[$_.ID] = $Server
}
}
While ((Get-Job).State -match 'Running')
{
foreach ($Job in Get-Job | where {$_.HasMoreData})
{
[System.Console]::BackgroundColor = $ColorHash[$Job.ID]
Write-Host $JobHash[$Job.ID] -ForegroundColor Black -BackgroundColor White
Receive-Job $Job
}
Start-Sleep -Seconds 5
}
[System.Console]::BackgroundColor = 'Black'
You can get the results by doing something like this after all the jobs have been received:
$array=#()
Get-Job -Name * | where{$array+=$_.ChildJobs.output}
.ChildJobs.output will have anything that was returned in each job.
function OutputJoblogs {
[CmdletBinding(DefaultParameterSetName='Name')]
Param
(
[Parameter(Mandatory=$true, Position=0)]
[System.Management.Automation.Job] $job,
[Parameter(Mandatory=$true, Position=1)]
[string] $logFolder,
[Parameter(Mandatory=$true, Position=2)]
[string] $logTimeStamp
)
#Output All logs
while ($job.sate -eq "Running" -or $job.HasMoreData){
start-sleep -Seconds 1
foreach($remotejob in $job.ChildJobs){
if($remotejob.HasMoreData){
$output=(Receive-Job $remotejob)
if($output -gt 0){
$remotejob.location +": "+ (($output) | Tee-Object -Append -file ("$logFolder\$logTimeStamp."+$remotejob.Location+".txt"))
}
}
}
}
#Output Errors
foreach($remotejob in $job.ChildJobs){
if($remotejob.Error.Count -gt0){$remotejob.location +": "}
foreach($myerr in $remotejob.Error){
$myerr 2>&1 | Tee-Object -Append -file ("$logFolder\$logTimeStamp."+$remotejob.Location+".ERROR.txt")
}
if($remotejob.JobStateInfo.Reason.ErrorRecord.Count -gt 0){$remotejob.location +": "}
foreach($myerr in $remotejob.JobStateInfo.Reason.ErrorRecord){
$myerr 2>&1 | Tee-Object -Append -file ("$logFolder\$logTimeStamp."+$remotejob.Location+".ERROR.txt")
}
}
}
#example of usage
$logfileDate="$((Get-Date).ToString('yyyy-MM-dd-HH.mm.ss'))"
$job = Invoke-Command -ComputerName "servername1","servername2" -ScriptBlock {
for ($i=1; $i -le 5; $i++) {
$i+"`n";
if($i -gt 2){
write-error "Bad thing happened"};
if($i -eq 4){
throw "Super Bad thing happened"
};
start-sleep -Seconds 1
}
} -asjob
OutputJoblogs -Job $job -logFolder "$PSScriptRoot\logs" -logTimeStamp $logfileDate
Run a job for each server in a list. I only want 5 jobs running at a time. When a job completes, it should start a new job on the next server on the list. Here's what I have so far, but I can't get it to start a new job after the first 5 jobs have ran:
$MaxJobs = 5
$list = Get-Content ".\list.csv"
$Queue = New-Object System.Collections.Queue
$CurrentJobQueue = Get-Job -State Running
$JobQueueCount = $CurrentJobQueue.count
ForEach($Item in $list)
{
Write-Host "Adding $Item to queue"
$Queue.Enqueue($Item)
}
Function Global:Remote-Install
{
$Server = $queue.Dequeue()
$j = Start-Job -Name $Server -ScriptBlock{
If($JobQueueCount -gt 0)
{
Test-Connection $Server -Count 15
}##EndIf
}##EndScriptBlock
}
For($i = 0 ;$i -lt $MaxJobs; $i++)
{
Remote-Install
}
PowerShell will do this for you if you use Invoke-Command e.g.:
Invoke-Command -ComputerName $serverArray -ScriptBlock { .. script here ..} -ThrottleLimit 5 -AsJob
BTW I don't think your use of a .NET Queue is going to work because Start-Job fires up another PowerShell process to execute the job.
You may take a look at the cmdlet Split-Pipeline of the module SplitPipeline.
The code will look like:
Import-Module SplitPipeline
$MaxJobs = 5
$list = Get-Content ".\list.csv"
$list | Split-Pipeline -Count $MaxJobs -Load 1,1 {process{
# process an item from $list represented by $_
...
}}
-Count $MaxJobs limits the number of parallel jobs. -Load 1,1 tells to pipe
exactly 1 item to each job.
The advantage of this approach is that the code itself is invoked synchronously
and it outputs results from jobs as if all was invoked sequentially (even
output order can be preserved with the switch Order).
But this approach does not use remoting. The code works in the current PowerShell session in several runspaces.
I run a script which performs many WMI-querys - but the cmdlet hangs if the server doesn't answer..
Is there any way I can make this (or any other cmndlet for that matter) timeout and exit if X seconds has passed?
Edit
Thanks to a tip from mjolinor the solution is to run this as -asjob and set a timeout in a while loop. But this is run from within a job already (started with Start-Job). So how do I know I am controlling the correct job?
This is my code from inside my already started job:
Get-WmiObject Win32_Service -ComputerName $server -AsJob
$Complete = Get-date
While (Get-Job -State Running){
If ($(New-TimeSpan $Complete $(Get-Date)).totalseconds -ge 5) {
echo "five seconds has passed, removing"
Get-Job | Remove-Job -Force
}
echo "still running"
Start-Sleep -Seconds 3
}
PS: My jobs started with Start-Jobs are already taken care of..
You could try the get-wmiCustom function, posted here. Wouldn't it be nice if get-wmiObject had a timeout parameter? Let's upvote this thing.
I've modified Daniel Muscetta's Get-WmiCustom to also support passing credentials.
I know this post is a little old, hopefully this helps someone else.
# Define modified custom get-wmiobject for timeout with credential from http://blogs.msdn.com/b/dmuscett/archive/2009/05/27/get_2d00_wmicustom.aspx
Function Get-WmiCustom([string]$Class,[string]$ComputerName,[string]$Namespace = "root\cimv2",[int]$Timeout=15, [pscredential]$Credential)
{
$ConnectionOptions = new-object System.Management.ConnectionOptions
$EnumerationOptions = new-object System.Management.EnumerationOptions
if($Credential){
$ConnectionOptions.Username = $Credential.UserName;
$ConnectionOptions.SecurePassword = $Credential.Password;
}
$timeoutseconds = new-timespan -seconds $timeout
$EnumerationOptions.set_timeout($timeoutseconds)
$assembledpath = "\\$Computername\$Namespace"
#write-host $assembledpath -foregroundcolor yellow
$Scope = new-object System.Management.ManagementScope $assembledpath, $ConnectionOptions
$Scope.Connect()
$querystring = "SELECT * FROM " + $class
#write-host $querystring
$query = new-object System.Management.ObjectQuery $querystring
$searcher = new-object System.Management.ManagementObjectSearcher
$searcher.set_options($EnumerationOptions)
$searcher.Query = $querystring
$searcher.Scope = $Scope
trap { $_ } $result = $searcher.get()
return $result
}
Glad my Get-WmiCustom function here http://blogs.msdn.com/b/dmuscett/archive/2009/05/27/get_2d00_wmicustom.aspx is useful.
when creating the job using get-wmiobject assign that job to a variable, then that variable can be piped into get-job for status or receive-job for results
$ThisJob = start-job -scriptblock {param ($Target) Get-WmiObject -Class Win32_Service -ComputerName $Target -AsJob} -ArgumentList $server
$Timer = [System.Diagnostics.Stopwatch]::StartNew()
While ($ThisJob | Get-Job | where {$_.State -imatch "Running"}){
If ($Timer.Elapsed.Seconds -ge 5) {
echo "five seconds has passed, removing"
$ThisJob | Get-Job | Remove-Job -Force
} # end if
echo "still running"
Start-Sleep -Seconds 3
} # end while
$Results = $ThisJob | where {$_.State -inotmatch "failed"} | receive-job
$Timer.Stop | out-null
The only two solutions I've seen for this problem are:
Run the queries as background jobs and put a timer on them, then stop/remove the jobs that run too long.
Fix your servers.
In addition to what has been said, not a bullet proof solution but consider pinging your servers first (Test-Connection), it can speed up execution time in case you have no responding machines.