Using Get-Job to test-connection, but quite different [duplicate] - powershell

This question already has answers here:
If using Test-Connection on multiple computers with -Quiet how do I know which result is for which computer?
(2 answers)
Closed 2 years ago.
It's my first post here, I'm tring to write scripts on PS on my own, now my target is to write script that checks if computer is online at network, for example: test-Connection 192.168.0.1, 2, 3 etc. Doing this one by one on loop for takes some time if some computers are offline, I've found some tutorials on this site to use -AsJob param, but I'm not really Sure how could it work. I mean I'd like to output every checked PC to excel, so i need if operator. eg:
if (Job1 completed successfull (computer pings)){
do smth}...
I need to get output from Job boolean (true/false), but one by one. I'm taking my first steps in PS, I've made program that checks it one by one in for loop, but as i said it take some time till my excel file fill...
I can see, that AsJob makes working more effective and I think it's important to understand it
Thanks and sorry for bad text formatting, by the time I'll go on with this!

In your example, in the Start-Job scriptblock you are trying to access $_ which is not available in the codeblock scope. If you replace $_ with $args[0] it should work since you are passing in the $ip value as an argument
Your Example
$ipki = Get-Content 'C:\Users\pchor\Desktop\ipki.txt'
foreach ($ip in $ipki) {
Start-Job -Name "$ip" -ScriptBlock {
Test-Connection $_ -Count 1 # <---- replace $_ with $args[0]
} -ArgumentList $_ # <----- change $_ to $ip
}
You'll probably also want to wait for all the jobs to finish. I recommend something like this
$computers = #(
'www.google.com'
'www.yahoo.com'
)
$jobs = $computers |
ForEach-Object {
Start-Job -ScriptBlock {
[pscustomobject]#{
Computer = $using:_
Alive = Test-Connection $using:_ -Count 1 -Quiet
}
}
}
# Loop until all jobs have stopped running
While ($jobs |
Where-Object { $_.state -eq 'Running' }) {
"# of jobs still running $( ($jobs | Where-Object {$_.state -eq 'Running'}).Count )";
Start-Sleep -Seconds 2
}
$results = $jobs | Receive-Job | Select-Object Computer, Alive
$results | Format-Table
Output
Computer Alive
-------- -----
www.google.com True
www.yahoo.com True
To modify the properties to what you want there are different ways of doing this. Easiest in this case is probably to use a calculated property
$newResults = $results |
Select-Object Computer,
#{Label = 'State'; Expression = { if ($_.Alive) { 'Online' } else { 'Offline' } } }
Objects will now look like this (I added another fake address to illustrate offline state)
Computer State
-------- -----
www.google.com Online
www.yahoo.com Online
xxx.NotAValidAddress.xxx Offline
You can then export the objects to csv using Export-csv
$newResults | Export-Csv -Path c:\temp\output.csv

Related

PowerShell Test-Connection -efficient Method

One Bronze medal = Newbi 😊, have scoured this site for years, so a million belated thanks, once again!
Just finished up a few different PowerShell ver 5.1 scripts that perform a test-connection on the same 2000 devices regularly.
Out to a csv file
And they are all slow, some minor speed improvements when tweaking it down to the bare bones.
I’ve scaled the script to the minimal, IPADDRESS and NAME only
I’ve run a few comparison tests against a batch file (ping 123.456.789.001 >> PingTest.txt ) and these tests APPEAR to run quicker than my PS script (will run a full apple to apples test tomorrow), but confident something is amiss in the PS code.
Am looking at arrays, and how piping works, but am afraid I’m putting the cart in front of the horse, or there is something going on with how PS handles the csv format and/or ping list in its memory
My most efficient current script below,
Is the following link pointing me in the right direction,? Specifically the asJob switch
PowerShell Mass Test-Connection
$info = "" | Select IPaddress,Name
$OutputFile = new-item -itemType File -path C:\Temp\Results.csv -force -value "IPaddress,Name`r`n" | out-null
Import-csv C:\Temp\GetList.csv | ForEach-Object {
if ($_.IPaddress) {
if (-Not (Test-Connection -ComputerName $_.IPaddress -Quiet -Count 2 -ErrorAction SilentlyContinue)) {
$info.IPaddress = $_.IPaddress
$info.Name = $_.Name
add-content -value "$($info.IPaddress),$($info.Name)" -path C:\Temp\Results.CSV
}
}
}
The export-csv is faster, thank you. I'm not sure if I have it in the right place, but it works, will run some tests on it tomorrow. I may have to include the passes tests though , still getting my head around the get-job cmdlet.
$info = "" | Select IPaddress,Name,Status
Import-csv c:\Temp\GetList.csv | ForEach-Object {
if($_.Ipaddress) {
if (-Not(Test-Connection -ComputerName $_.IPaddress -Quiet -Count 2 -ErrorAction SilentlyContinue)) {
$info.IPaddress = $_.IPaddress
$info.Name = $_.Name
$info.Status = "Failed"
$info | export-csv C:\Temp\Results1.csv -Force -Notypeinformation -Append
}
}
}
$list = Import-Csv C:\Temp\GetList.csv
ForEach ($item In $list) {
Start-Job -ScriptBlock {
param($item)
if (Test-Connection -Computername $item.IPaddress -Quiet -Count 1) {
Add-Content -value "$($item.IPaddress),$($item.Name),$($item.Stauts)" -Path C:\Temp\xlistlist.csv
$list | Export-csv c:\Temp\xCSvreults.csv -Force -NoTypeInformation -Append
}
} -argumentlist $list
}
Thanks Santiago, I did some exploring here, just ran out of time for the day. THANK YOU you for the code examples they cleared a few things up for me :-) –
Have Computer
Dec 2 at 3:59
Would you mind adding some inline comments so I can follow along? Just trynna understand multi-threading (using runspaces) a bit better. –
Abraham Zinala
Dec 2 at 4:58
1
#AbrahamZinala is there a specific part you're struggling to understand? i'm not an expert on this and wouldn't like to give false information. Might be better to pick up all the parts you don't understand and ask a new question –
Santiago Squarzon
Dec 2 at 12:19
Nah man, sorry, I figured it out lol –
Abraham Zinala
Dec 2 at 13:43
1
#AbrahamZinala the only hard part to understand is the [powershell] instance part imo, and you can think of it as a Start-Job but much faster and less memory consuming, you add your scriptblock with .AddScript({...}) and then the parameters with .AddParameters([hashtablehere]). It's important to save the PSInstance in a variable so that we can get the output out of it and it's handler (Status = $psinstance.BeginInvoke()) to know when the instance has completed. The rest is just pure blueprint, once you have one you can copy paste it :P –
Santiago Squarzon
Dec 2 at 13:50
#HaveComputer I have no idea what your comment means. –
Santiago Squarzon
Dec 5 at 1:10
the 2 solutions presented work much faster, my code however is lacking. –
Have Computer
Dec 5 at 1:16
#HaveComputer I know that, this can perform 50x faster or even more depending on hardware and bandwidth. –
Santiago Squarzon
This is a good place where you can use runspaces, I would love to test if Test-Connection -AsJob performs better than this but for some reason it is not available on PS Core on Linux.
Code below took around 10 seconds to scan 254 IPs using my private network IP range. There is a lot of tweaking that can be done, i.e. you can poke around the $Threshold variable, it's currently running 100 runspaces at a time, Count and TimeoutSeconds for Test-Connection have been set to 2 you can tweak that too.
$results variable can be exported using Export-Csv.
# Change this value for tweaking
$Threshold = 100
$RunspacePool = [runspacefactory]::CreateRunspacePool(1, $Threshold)
$RunspacePool.Open()
# This is for testing, use your CSV here instead
# => $list = Import-Csv C:\Temp\GetList.csv
$list = 1..254 | ForEach-Object {
[pscustomobject]#{
IPAddress = "192.168.1.$_"
Hostname = "ExampleHost$_"
}
}
$scriptBlock = {
param($ip, $hostname)
$params = #{
Quiet = $true
Count = 2
TimeoutSeconds = 2
ComputerName = $ip
}
$status = Test-Connection #params
[pscustomobject]#{
Hostname = $hostname
IPAddress = $ip
Status = ('Failed','Success')[[int]$status]
}
}
$runspaces = foreach($line in $list)
{
$params = #{
ip = $line.IPAddress
hostname = $line.Hostname
}
$psinstance = [powershell]::Create().AddScript($scriptBlock).AddParameters($params)
$psinstance.RunspacePool = $RunspacePool
[pscustomobject]#{
Instance = $psinstance
Status = $psinstance.BeginInvoke()
}
}
while($runspaces.Status.IsCompleted -contains $false)
{
Start-Sleep -Milliseconds 500
}
$results = $runspaces.ForEach({ $_.Instance.EndInvoke($_.Status) })
$RunspacePool.Dispose()
$results Sample:
Hostname IPAddress Status
-------- --------- ------
ExampleHost1 192.168.1.1 Success
ExampleHost2 192.168.1.2 Failed
ExampleHost3 192.168.1.3 Success
ExampleHost4 192.168.1.4 Failed
ExampleHost5 192.168.1.5 Success
ExampleHost6 192.168.1.6 Failed
ExampleHost7 192.168.1.7 Failed
ExampleHost8 192.168.1.8 Failed
ExampleHost9 192.168.1.9 Failed
ExampleHost10 192.168.1.10 Failed
...
...
Start-Job -ScriptBlock { Test-Connection -computername (Get-Content -Path “C:\Temp\GetList.csv”) }
Its lacking the fundamentals, works, DE fast.

How to Invoke below script block using Invoke-parallel

This Invoke-Parallel is taken from here
Below is my script block
$scriptblock ={
get-service -ComputerName $parameter.computername | where {$_.name -eq $parameter.serviceName }
}
below is a custom object
$pscustomobject = #()
$pscustomobject += [pscustomobject]#{
Computername ='server1'
Servicename ="service1"
}
$pscustomobject += [pscustomobject]#{
Computername ='server2'
Servicename ="service2"
}
I tried using Invoke-Parallel using below method ,but this doesnt work
Invoke-Parallel -ScriptBlock $scriptblock -Parameter $pscustomobject
"server1","server2" | Invoke-Parallel -ScriptBlock $scriptblock -Parameter $pscustomobject
Few services exist in few servers and on few others,they dont,so created a custom object which tightly maps services to servers.
Any ideas would be greatly helpfull
The -Parameter switch makes the properties available to each item in the script block. I think if you make a small modification like this, then it should work:
$scriptblock ={
$thisServer = $_
$thisServerParams = $parameter.Where({$_.Computername -eq $thisServer})
get-service -ComputerName $thisServerParams.computername | where {$_.name -eq $thisServerParams.serviceName }
}
We can use this code above to find the right properties we should use for each server. With the code before, we were effectively using Invoke-Parallel to run the same command on all servers each time. And the logic wouldn't work for matching services in the Where block because it would compute to
$pscustomobject.ServiceName
service1
service2
PS C:\Users\Stephen> $pscustomobject.ServiceName.GetType()
IsPublic IsSerial Name BaseType
-------- -------- ---- --------
True True Object[] System.Array
An individual service coming back from Get-Service would never equal to System.Array
Thanks to Foxdeploy,found one more way to achieve what i need,below method is more flexible for me,since..when i pass two services,one service may take a lot of time to start or stop and may hold data from another service as well
$pscustomobject | Invoke-Parallel -ScriptBlock {
$computername = $_.computername
$servicename = $_.servicename
get-service -ComputerName $($computername) | where {$_.name -eq $($serviceName) }
}
I might be wrong but I believe this would be faster, using builtin Powershell cmdlet and also looks cleaner imo:
$servers=#(
'server1'
'server2'
)
$scriptblock={
switch($env:COMPUTERNAME)
{
'server1'{Get-Service service1}
'server2'{Get-Service service2}
}
}
$result=Invoke-Command -ComputerName $servers -ScriptBlock $scriptblock
Edit:
For the sake of demonstration, here I'm waiting 10 seconds and then resolving a easy mathematical equation on 7 servers depending on their name 3 pairs of them start with the same name. If this was a linear invocation it should've taken 10+10+10+10 seconds yet it only took 15 seconds for all of them. This demonstrates that you can execute different commands on different remote computers at the same time.

Taking input from one PSSession and sending it to another

Like many others, my background is in Linux with no powershell experience. So this object oriented programming is messing me up.
I need to search through VMware Horizon for VMs with users assigned to them, then check if they are disabled in AD. If they are disabled in AD I want to recycle the VM.
At the moment I am pulling the SIDs for the users from VMware Horizon, but when I try to use these in an invoke-command against AD I receive the following error
"Object reference not set to an instance of an object"
The Script so far
function getlist() {
$temp=Invoke-Command -ComputerName $vdiserver -ScriptBlock { add-pssnapin vmware.view.broker; get-desktopvm | select user_sid }
$list=$temp | Select-Object user_sid
#$list
}
$vdi1="server1"
$vdi2="server2"
$test=Test-Connection -ComputerName $vdi1 -Quiet
$test2=Test-Connection -ComputerName $vdi2 -Quiet
if ($test -eq "True"){
$vdiserver=$vdi1
getlist
}
elseif ($test2 -eq "True"){
$vdiserver=$vdi2
getlist
}
else {echo "No servers to connect to"}
ForEach ($user in $list) #{
#echo $user
#sleep 1
#}
{Invoke-Command -ComputerName domaincontroller -ScriptBlock {param($p1) get-aduser -identity $p1 } -argumentlist $user}
So this object oriented programming is messing me up.
So you're trying to revert to shell script, and writing twice as much code to do achieve half as much work.
The most important bit you're missing is to imagine an object as a collection of things - like, imagine you're working with /etc/passwd and each line has a user ID and a group ID and a home directory and a login shell.. and you're passing the entire line around at once, that's your analogous object.
An object has many properties, just like that (but overall more capable).
When you Select user_sid you're choosing that field to stay in the 'line', but the line is still something like :::user_sid:::: with the other fields now empty. (Approximately). But they're still there and in the way. To work with it directly, you have to get it out of the 'line' entirely - throw the container away and just have the user_sid outside of it.
get-desktopvm | select user_sid
->
get-desktopvm | select -expandproperty user_sid
which makes "sid1", "sid2", "sid3", but no containers for each sid.
This
function getlist() {
$temp=Invoke-Command -ComputerName $vdiserver -ScriptBlock { add-pssnapin vmware.view.broker; get-desktopvm | select user_sid }
$list=$temp | Select-Object user_sid
}
is essentially saying
function getlist() {
#do any amount of work here, and throw it all away.
}
Because the function returns nothing, and it doesn't change any data on disk or anything, so when the function finishes, the variables are cleared out of memory, and you can't use them afterwards.
This:
if ($test -eq "True"){
is a bit of a nonsense. It might work, but it's not working how you expect because it's happenstance that "a string with content" compared to a boolean True is True, regardless of the string containing the English word "True" or not. But it's also redundant - $test is itself true or false, you don't need to compare True with anything. if ($test). Or even if (Test-Connection -ComputerName $vdi -Quiet)
But stillll, so much work. Just connect to them all, and let it fail for the ones it can't contact. Maybe add -ErrorAction SilentlyContinue if you don't want to see the error.
$VMs = Invoke-Command -ComputerName Server1,Server2 -ScriptBlock {
Add-PsSnapin vmware.view.broker
Get-DesktopVm
}
Now you have all the VMs, get the user enabled/disabled state
foreach ($VM in $VMs) {
$Sid = $VM.user_sid
$AdEnabled = Invoke-Command -ComputerName domaincontroller -ScriptBlock {
(Get-AdUser -Identity $using:Sid).Enabled
}
$VM| Add-Member -NotePropertyName 'AdEnabled' -NotePropertyValue $AdEnabled
}
Now you should ideally have $VM as an array of objects, each one having all the VM Desktop properties - and also the True/False state of the AD Enabled property for that user account.
$VM | Out-Gridview
or
$VM | Export-Csv Report.csv
or
$VM | Where-Object { -not $_.AdEnabled }

Multiple column output using a hashtable

I am trying to create a Hash Table that contains 3 columns.
SERVER_NAME PROCESS_NAME SERVER_STATUS PROCESS_AVAILABLE
SERVER1 app1.exe RUNNING YES
SERVER1 app2.exe RUNNING NO
SERVER2 app1.exe OFFLINE NO
SERVER2 app2.exe OFFLINE NO
SERVER3 app1.exe RUNNING YES
SERVER3 app2.exe RUNNING YES
So far, I've tried this
$SERVERLIST = Get-Content "$PSScriptRoot\servers\serverManager.bin"
$PROCESSMONITOR = Get-Content "$PSScriptRoot\process\application.bin"
$testList = #{Name=$SERVERLIST;Process=$PROCESSMONITOR}
The list of servers are in the "serverManager.bin" file. This is a CSV file that contains a list of the servers.
The list of processes that I am interested in monitoring are in the "application.bin" file. This is a CSV file that contains a list of the applications (as seen by PowerShell). [see code below]
Get-Process -ComputerName $server -name $process -ErrorAction SilentlyContinue
I want to build a report which tells an admin which server is running and which process is running from the list that we are interested in monitoring.
I can check if the process is running
I can check if a server is online
My question is what do I need to do to get output like what's posted above
While hashtables play a part in this answer you are not looking for hashtables at all really. Looking at about_hash_tables
A hash table, also known as a dictionary or associative array, is a
compact data structure that stores one or more key/value pairs.
While you can nest whatever you want into the value you really are not looking for a hashtable. What I think you want is a custom PowerShell object that contains the results of each of your queries.
Get-Process does take arrays for both -Computer and -Name but they would omit results where either the computer does not exist or the process does not. Since you want that information you need to run a single cmdlet for each computer/process pair.
I use a hashtable only to create each individual "row" which is converted to a PowerShell object and collected as an array. I don't want to confuse but I know this working with at least 2.0 which is why I do it this way.
$SERVERLIST | ForEach-Object{
$computer = $_
$PROCESSMONITOR | ForEach-Object{
$process = $_
$props = #{
Server_Name = $computer
Process_Name = $process
}
# Check if the computer is alive. Better this was if $processes is large
If(Test-Connection $computer -Quiet -Count 1){
$props.Server_Status = "Running"
$result = Get-Process -Name $process -ComputerName $computer -ErrorAction SilentlyContinue
If($result){
$props.Process_Available = "Yes"
} else {
$props.Process_Available = "No"
}
} else {
$props.Server_Status = "Offline"
$props.Process_Available = "No"
}
New-Object -TypeName psobject -Property $props
}
} | Select Server_Name,Process_Name,Server_Status,Process_Available
So now that we have a proper object you can now use other cmdlets like Where-Object, Sort-Object and etc.

Display test-connection successes and failures in Out-Gridview

I am trying to get a list of servers and the last time they rebooted to show in a table. However, if it doesn't respond to a ping, I just need it to show in the list. I can't seem to figure out how to get it to add to the table after else.
Import-CSV $Downtime | % {
if(Test-Connection $_.server -Quiet -count 1){
Get-WmiObject Win32_OperatingSystem -ComputerName $_.server |
select #{LABEL="Name"; EXPRESSION = {$_.PSComputerName}}, #{LABEL="Last Bootup"; EXPRESSION = {$_.convertToDateTime($_.LastBootupTime)}}
}
else{#{LABEL="Name"; EXPRESSION = {$_.server}}
}
} | Out-GridView
I can always save the else results in a text file but this would be more convenient.
You need to make the same object, with the same properties!, in both cases so that PowerShell will understand the association between the two. The follwing example builds a custom hashtable using the if/else and outputs the object for each loop pass.
Import-CSV $Downtime | ForEach-Object {
$props = #{}
$server = $_.server
if(Test-Connection $server -Quiet -count 1){
$wmi= Get-WmiObject Win32_OperatingSystem -ComputerName $server
$props.Name = $wmi.PSComputerName
$props."Last Bootup" = $wmi.convertToDateTime($wmi.LastBootupTime)
}else{
$props.Name = $server
$props."Last Bootup" = "Could not contact"
}
New-Object -TypeName psobject -Property $props
} | Out-GridView
I used $server as the $_ changes context a couple of time so we wanted to be able to refer to the current row in the CSV we are processing.
I don't know what your PowerShell version is so I will assume 2.0 and create objects that support that.
In both cases an object is created with a Name and Last Bootup property which is populated based on the success of the ping.
As an aside I had a similar question a while ago about created similar object based output.