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Category: Server2012R2

Powershell Desired State Configuration simple example

While still in 'Devop Mood', let's quickly figure out Desired State Configuration.

This image gives a nice overview of the DSC architecture:

Requirements

If you have a Windows 2012 R2 Server with the latest updates and KB2883200 installed, you're good to go. Check it like so:
wmic qfe | find "KB2883200"

What Powershell Modules are there installed anyway? Go ahead, open a Powershell console and type $env:PSModulePath -split ";"
This displays the locations on your PC where there are Powershell modules installed.

PS C:\Users\vagrant> $env:PSModulePath -split ";"
C:\Users\vagrant\Documents\WindowsPowerShell\Modules
C:\Program Files\WindowsPowerShell\Modules
C:\Windows\system32\WindowsPowerShell\v1.0\Modules\

Now if you cd into C:\Windows\system32\WindowsPowerShell\v1.0\Modules\ you get to see all the modules. If all is well, one of them is PSDesiredStateConfiguration. This is where the DSC commandlets are hidden.

Resources

A resource is an 'object' which you can configure with DSC. There are 3 sources for resources.

Out of the box resources
Out of the box with Powershell v4, there are modules for File, Registry, Services etcetera. To see the complete list, do:

PS C:\> Get-DscResource | select name

This outputs:

Name
----
File
Archive
Environment
Group
Log
Package
Registry
Script
Service
User
WindowsFeature
WindowsProcess

Community resources
The Powershell community has also written some modules for DSC resources, like DNS, Active Directory and Hyper-V. You can find them here and they are prefixed with a c.

Experimental resources
The Powershell team itself also provides some experimental resources which you can find here. These resources are prefixed with an x.

You can download these resources and add them to the $env.PSModulePath folder. Which is in my case: C:\Windows\system32\WindowsPowerShell\v1.0\Modules\.

Create your first configuration

These steps describe the DSC process:

  • Add the required DSC resources
  • Create a configuration script
  • Execute the script to generate a MOF file
  • Apply the MOF to the target nodes

Now let's start with adding a folder named "c:\Replica" on every node. That means we could use the File resource, which comes out of the box. Now, how to use this file resource? Luckily, the Powershell folks have made things very easy for us. We can just type get-dscresource File -syntax and lo and behold:

PS C:\> Get-DscResource File -Syntax
File [string] #ResourceName
{
    DestinationPath = [string]
    [ Attributes = [string[]] { Archive | Hidden | ReadOnly | System }  ]
    [ Checksum = [string] { CreatedDate | ModifiedDate | SHA-1 | SHA-256 | SHA-512 }  ]
    [ Contents = [string] ]
    [ Credential = [PSCredential] ]
    [ DependsOn = [string[]] ]
    [ Ensure = [string] { Absent | Present }  ]
    [ Force = [bool] ]
    [ MatchSource = [bool] ]
    [ Recurse = [bool] ]
    [ SourcePath = [string] ]
    [ Type = [string] { Directory | File }  ]
}

So this basically explains how to use the File resource.

Fire up Powershell ISE and start type:

Configuration MyFirstConfig {

Node DSC1 {
    
    File SyncDir {
        DestinationPath = "c:\replica"
        Type = "Directory" 
        Ensure = "Present"   
    }
  }
}

MyFirstConfig -OutputPath c:\DSC

If you execute this script a MOF file will be created in c:\DSC.

Apply the MOF

Now go ahead and type: Start-DscConfiguration -Path c:\DSC

This will output:

PS C:\Windows\System32\WindowsPowerShell\v1.0\Modules> Start-DscConfiguration -Path c:\DSC

Id     Name            PSJobTypeName   State         HasMoreData     Location             Command
--     ----            -------------   -----         -----------     --------             -------
8      Job8            Configuratio... Running       True            DSC1                 Start-DscConfiguration...

And if all is well there is indeed a folder named 'replica' on your C:\ drive.

Conclusion

This was a very simple example of Powershell DSC. I think it is quite nice and I am planning to explore its possibilities in the near future (like tomorrow or so).

 
 
 


Quickly build a Windows lab with VirtualBox, Packer, Vagrant and Chocolatey

logos

I'm preparing a Powershell training for work and I needed an easy lab with virtual machines which I can easily distribute among the students. It should obviously all be Windows based.

So I started out working with Windows 10 and Vagrant to create a virtual lab, as I did on my Mac and Ubuntu box before, and I am very happy and (surprised) to announce that it works very smoothly on Windows. And I used Packer to create a Windows base box for Vagrant.

So I had great fun setting up my training lab and it would be a shame to keep it all for myself. So here goes. The Buttonfactory goes Devops!

Install Windows 10 Technical Preview and Chocolatey

Unfortunately, the preview of Windows 10 is not available anymore. If you look hard enough, I think it is possible to grab an iso somewhere.
By the way, the rest of these directions work also under Windows 7, 8 and 8.1.

screen1

Install Chocolatey
After installing Windows 10 I would advise to install Chocolatey. Chocolatey is like Ninite on the command line (or like apt-get for Windows if you will) and it is going te be very important in the future.

Open a command prompt as Administrator and paste this command in your terminal:

@powershell -NoProfile -ExecutionPolicy Bypass -Command "iex ((new-object net.webclient).DownloadString('https://chocolatey.org/install.ps1'))" && SET PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin

(Or just head over to https://chocolatey.org/ and follow the installation instructions).

 

Install Cmder
Then the first thing todo is install Cmder, a perfect replacement for the Windows terminal (which sucks a bit).
Fire up the command prompt as an admin and type:

//
cinst cmder -y
//

The Cmder binaries are installed in c:\tools. It is added to the path so you can just fire it up (start, run) and type Cmder.
Cmder also incorporates Msysgit which brings you, apart from Git, a light set of GNU tools as well like ls, grep, awk and vim, which I adore.

You can add another tab with a new console and tick 'Run as administrator' for convenience.
2015-07-19 14_17_18-ConEmu

 

 

 

 

And you can designate a tab for Powershell as well:
2015-07-19 14_19_59-Cmder

 

 

 

 

 

 

Install VirtualBox, Vagrant and Packer

This is also possible from Chocolatey.

//
cinst virtualbox vagrant -y
//

Add vagrant to the path. My path looks like this: C:\tools\cmder;C:\PROGRA~2\Oracle\VirtualBox;c:\HashiCorp\Vagrant\bin

The next steps to install Packer are:

  • Open Cmder
  • Type: mkdir \Vagrant
  • Type: cd \Vagrant
  • Type: git clone https://github.com/joefitzgerald/packer-windows.git
  • Cd into packer-windows and see what has been downloaded
  • Now download packer and extract all contents to the packer-windows folder. (I think that is convenient)

Build a Windows Server 2012 R2 base box

This paragraph is based on this blog post from Rui Lopes.

We are going to edit the windows_2012_r2.json a bit to adjust it to our needs:

  • On line 38: set headless to false to see what is going on
  • On line 42: change the ssh_wait_timeout from 4h to 8h (to have enough time to install all updates)
  • On line 76: Remove the ./scripts/compact.bat (it takes ages to run) and the ./scripts/chef.bat (we are not gonna need it) lines.
  • You might want to change the answer file to change the Culture, but that can be done in the Vagrantfile later.

Now we are ready to build the box. Make sure you are in the c:\vagrant\packer-windows folder and type:

//
packer build -only virtualbox-iso windows_2012_r2.json
//

And now we wait. This takes forever. I'd suggest you go for a walk or perhaps to bed early. But the price is big!

Add the Windows Server 2012 R2 base box to Vagrant

When you return from your other extra curricular activity, you will see a box file is created in the c:\vagrant\packer\packer-windows folder.
You should add this box to Vagrant:

//
vagrant box add --name windows_2012_r2 windows_2012_r2_virtualbox.box
//

This will also take a short time.

It will add the box to C:\Users\\.vagrant.d\boxes\windows_2012_r2\0\virtualbox:

2015-07-19 15_27_06-Cmder

You can basically get rid of the box file in c:\vagrant\packer\packer-windows now, or copy it to an USB drive or so because for now it is not longer needed.

Fire up the Virtual Server already!

  • Go to c:\Vagrant and create a dir for the server (mine is called DSC1)
  • cd into DSC1
  • Type vagrant init
  • Edit the Vagrantfile that this creates and make it to look like so:
    Vagrant.require_version ">= 1.6.2"
    
    $root_provision_script = <<'ROOT_PROVISION_SCRIPT'
    & $env:windir\system32\tzutil /s "W. Europe Standard Time"
    ROOT_PROVISION_SCRIPT
    
    Vagrant.configure("2") do |config|
        config.vm.define "DSC1"
        config.vm.box = "windows_2012_r2"
        config.vm.hostname = "DSC1"
    
    
        config.vm.provider :virtualbox do |v, override|
            v.gui = true
            v.customize ["modifyvm", :id, "--memory", 2048]
            v.customize ["modifyvm", :id, "--cpus", 2]
        end
    
        config.vm.network "private_network", ip: "10.10.10.4"
        config.vm.provision "shell", inline: $root_provision_script
    
    end
  • Save it
  • Type: vagrant up

When it is finished, you type vagrant rdp and you can log on to your box.
(Username vagrant, password vagrant).

2015-07-19 15_42_33-Quickly build a Windows lab with VirtualBox, Packer, Vagrant and Chocolatey _ Th

Now to halt the box: you type: vagrant halt.
To destroy the box: you type vagrant destroy.
And you can start again with a clean slate in seconds with vagrant up.

Create more folders for other servers, adjust the Vagrantfile (server name, IP address) and spin them up.

Extra: add Chocolatey to the Vagrant box

You can provision your Vagrant boxes with Chocolatey, and install Cmder and Notepad2 (or whatever packages you might need from the Choco repos). To do so, change the Vagrantfile like so:

Vagrant.require_version ">= 1.6.2"

$root_provision_script = <<'ROOT_PROVISION_SCRIPT'
#adjust the time zone:
& $env:windir\system32\tzutil /s "W. Europe Standard Time"

#install Chocolatey
iex ((new-object net.webclient).DownloadString('https://chocolatey.org/install.ps1'))

#and install Cmder and Notepad2
choco install cmder notepad2 -y
ROOT_PROVISION_SCRIPT

Vagrant.configure("2") do |config|
    config.vm.define "DSC1"
    config.vm.box = "windows_2012_r2"
	  config.vm.hostname = "DSC1"

	        config.vm.provider :virtualbox do |v, override|
		        v.gui = true
		        v.customize ["modifyvm", :id, "--memory", 2048]
		        v.customize ["modifyvm", :id, "--cpus", 2]
			    end
      config.vm.network "private_network", ip: "10.10.10.4"
      config.vm.provision "shell", inline: $root_provision_script
end