Our mission
on this page is start a named Windows service. If necessary, we can modify the script to stop, or even
Restart the service. In order to get a grounding in the PowerShell syntax associated with this 'Service' family of commands, I suggest that
you begin with my Get-Service page.
Our mission is to start one (or more) of your operating system's services. We can also adapt the script to stop services, but that is less
exciting. It is also worth mentioning that another member of this family is called
Restart-Service.
The result of my preliminary experiment reveals that it's not possible to start a service
whose start-up type is currently set to, 'Disabled'. Good news; a walk-through with the Services GUI reveals that if you switch a service from Disabled to Manual, then you can start it.
Incidentally, I believe in the maxim: 'Any thing that you can do by clicking in a GUI, you can equal (or exceed) in a PowerShell script'.
In Windows Server 2003 days I choose the Alerter service for testing, partly because it's relatively harmless service, and partly because its name is near the top of the list!
However, since Alerter has been removed from Windows 7 and Server 2008, I
have
chosen PLA (Performance Logs and Alerts) to test PowerShell's service
cmdlets.
Instructions: Pre-requisite: Visit Microsoft's site and download the correct version of PowerShell for your operating system.
Launch PowerShell, the ISE GUI would be best.
Copy the four lines of code below (into memory)
Right-click on the PowerShell symbol
Edit --> Paste
Press enter to execute the code.
Preliminary Script
Let us check the service's status, and also let us 'warm up' with Get-Service before we employ other members of the service family.
# PowerShell cmdlet to check a service's status $srvName = "PLA" $servicePrior = Get-Service $srvName $srvName + " is now " + $servicePrior.status
Learning Points
Note 1: I have decided to introduce the variable $srvName to hold the value of the service.
Hopefully this will emphasise the name of the service, and prompt
you to change it as necessary for your project.
Note 2: Observe how I mix the ''literal phrases'' with the
$variables and properties to produce a meaningful output.
The Main
Event - Starting Service PLA (Performance Logs and Alerts)
Windows 7 and Server 2008 do not have an Alerter service, this is
why I now use PLA (Performance Logs and Alerts) to test PowerShell's
Start-Service.
Check Status - And Start Service
# PowerShell cmdlet to start a named service $srvName = "PLA" $servicePrior = Get-Service $srvName "$srvName is now " + $servicePrior.status
Set-Service $srvName -startuptype manual Start-Service $srvName $serviceAfter =
Get-Service $srvName "$srvName is now " + $serviceAfter.status
Learning Points
Note 3: Observe how the speech marks are slightly different in this script
compared with the previous: "$srvName is now " + $servicePrior.status
compared with $srvName + " is now " + $servicePrior.status
My
points are: a) Experiment yourself. b) To some extent, these learning scripts leave traces of my thinking process.
Note 4: I prepared the above script to help you appreciate the factors needed to control a Windows Service. It also reflects my thinking process of how I learn about a
command. On the other hand, for a production script you could take a much more ruthless approach and simplify the script thus:
Simple Script to Start the Service
# PowerShell set, then start a service Clear-Host
Set-Service PLA -startuptype manual Start-Service PLA
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In real life, you may want a script which ensures that services such as: Telnet, Messenger and Routing and Remote Access are Stopped. Just for testing, you may need a script which reverses
Start-Service, just to be sure that it really is working as designed. Either way, here is a script which stops the service defined by $srvName.
# PowerShell cmdlet to stop the Perf log and alert service $srvName = "PLA" $servicePrior = Get-Service $srvName "$srvName is now " + $servicePrior.status Stop-Service $srvName $serviceAfter = Get-Service $srvName
Set-Service $srvName
-startuptype disabled "$srvName is now " + $serviceAfter.status
Learning Points
Note 6: Observe how this script is the mirror image of the
Start-Service script. It even disables the service once it has stopped. If you remember, when
Example 1 wanted to start a service, it must first make sure the -startuptype is set to manual.
In Order to Explain a Trap - I Digress:
What's in a Name? What do these groups of services have in common?
Group A Alerter,
Messenger, WebClient
Group B Print Spooler, Telnet, Telephony and Windows Time
More importantly, why won't PowerShell's service family interact with Group B?
The Answer: Some
services have a 'Display Name' which differs from their 'Service Name', for example Telnet and Tlnsvr. How did I find this out? When I tried to start 'Telnet', or 'Print Spooler', nothing happened.
Yet if I had a manual walk-through in the Service GUI, no problem. Then I ran Get-Service * and observed the two columns, Name and also Display Name. What threw me into confusion was Group A, where
both names are the same.
Just to emphasise, if you wish to control 'Print Spooler', you need to script its Name - 'Spooler'. If you double-check with the command: Get-Service s* you see Name: Spooler, Display
Name: 'Print Spooler'.
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powerful search options.
A classic service to practice the
Restart-Service command is, "Spooler".
One reason for choosing this particular service is that the printer gives more trouble than any other piece of hardware, and sometimes
Restarting the Spooler cures the problem. The inferior, but ruthless method of curing such printer
jams is to reboot the computer. However, if the computer is also a server, this method is undesirable.
The real life situation of a jammed printer spooler is not straightforward. The point is
that it APPEARS to be running, but in fact it's not working. The smartest solution is to
Restart the service. As with previous examples, when you are learning, open the services.msc GUI and
experiment with the settings. What you will discover is that you can also
Restart a service that has stopped.
Production Script
To
achieve a restart, all you really need is this one-liner:
Restart-Service "Spooler"
Learning Script
# PowerShell cmdlet to Restart the Spooler service $srvName = "Spooler" $servicePrior = Get-Service $srvName "$srvName is now " + $servicePrior.status
Set-Service $srvName -startuptype manual Restart-Service $srvName $serviceAfter
= Get-Service $srvName "$srvName is now " + $serviceAfter.status
Learning Points
Note 7: My biggest fear is that in a production script I will misspell the name of the service. Thus, check for success by observing this system message:
WARNING: Waiting
for service 'Print Spooler (Spooler)' to finish starting...
Note 8: There will be variations depending on
which operating system you are using.
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One aspect of remoting in PowerShell v 2.0 is simply to append
-computerName xyz to the command that you ran on the local machine.
For further research try:
Surprise! Get-Service is amongst the cmdlets that support
remoting, but stop, start and Restart-Service are not on the list.
More bad news, stop, start and Restart-Service really don't work on
network machines. Thus you have to employ different techniques
such as Get-WmiObject and InvokeMethod. Alternatively, you could
enter-PSSession and then run Restart-Service as if you were on the local
machine. However, to get that working you have to first
install and setup WinRM
More Research on PowerShell's Get-Service
Everytime I run a check of cmdlet's capabilities with Get-Help I discover
a new parameter, or useful example. In this case I am reminded of the
-DisplayName and -DependentServices parameters. Try the command for
yourself.
Clear-Host Get-Help Get-Service -full
The Service Family (Each member has a different verb)
Talking of research, I also like to know more about 'sister' commands;
for example, Restart-Service is much neater than using Stop-Service, then
Start-Service.
Get-Service: Useful for listing
the services Set-Service:
Crucial parameter -startuptype
Start-Service: The verb 'start' says it all Stop-Service: Handy for
scripts which prevent unwanted services running e.g. Telnet Restart-Service: A nice
touch by the creator's of PowerShell; this cmdlet removes the need to
explicitly stop then start the service.
If your mission is to master the Start-Service
command, commence with Get-Service. Once you have mastered the rhythm
of the Get-Service verb-Noun pair, move on to the Start, Stop, and
Restart-Service family of PowerShell commands. For scripting purposes, make sure that you use the true Service Name, and avoid
the Service's Display Name. A final piece of advice, open the Service GUI so that you can double-check that what your script is doing is what you intended.
If you like this page then please share it with your friends
See more PowerShell examples of process and service
Please email me if you have a better example script. Also please report any factual mistakes, grammatical errors or broken links, I will be happy to correct the fault.
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