Windows Server 8

KnowledgeBase: Errors connecting to Windows Server 2008 R2 or Windows Server 2012 Device Manager remotely

Last week, Microsoft has released a KnowledgeBase article titled Errors connecting to Windows Server 2008 R2 or Windows Server 2012 Device Manager remotely.

In this article, Microsoft tells us the reason why we can’t connect remotely to:

  • Windows Server 2012 Device Manager from a Windows 8-based computer
  • Windows Server 2012 Device Manager from a Windows 7-based computer
  • Windows Server 2008 R2 Device Manager from a Windows 8-based computer
  • Windows 8 Device Manager from a Windows 7-based computer

The reason behind this, is the fact that Remote access to the Plug and Play (PNP) RPC interface has been removed in Windows 8 and Windows Server 2012.

As a resolution, Microsoft suggests to login to the computer locally to utilize Device Manager.

While this sounds like some sort of workaround for Full Installations, on Server Core installations of Windows Server 2012, this won’t be possible, since devmgmt.msc is not a recognized command.

The work-around for Server Core installations is to install the Windows Server Management Infrastructure role. Use the following command line to perform this action:

Install-WindowsFeature Server-Gui-Mgmt-Infra –Restart

    

Related KnowledgeBase articles

2781106 Errors connecting to Windows Server 2008 R2 or Windows Server 2012 Device Manager remotely

What would you choose? Flexibility vs. Disk Space

Hard DiskWith Windows Server 2012, Microsoft has changed its Server Core strategy. In short, Microsoft now focuses on the flexibility to switch the Graphical User Interface (GUI) from a full installation to a minimal shell and even further down to server core, instead of reducing the disk space needed to run the Operating System. (the ‘disk foot print’)

Is this bad?

Many systems administrators will tout the advantages of a small disk foot print in the following ways:

  1. Faster to implement
    With less data on a (virtual) disk, the Operating System can be deployed faster initially. When deploying over the network, less data needs to be transmitted, resulting in a faster deployment and also less strain on the network.
      
  2. Less hardware needed
    If you need less disk space, you can use cheaper disks in your systems. When deploying virtual servers, less expensive SAN storage is needed.
      
  3. More secure
    Less data on a disk results in a significantly smaller attack surface. If there’s less code in use, then less errors in code can be leveraged.

However, these three arguments are moot points.

First of all, I’ve rarely seen an admin sitting idly by a server watching it install its Operating System. If he/she is not documenting what he/she just did or already preparing next steps in the deployment process, he/she is probably checking out social media or solving another incident.

Second, disk hardware is not expensive anymore. The difference between a Server Core installation and a Full installation in Windows Server 2008 R2 is 7GB. You cannot buy physical disks in this size range. Also, on SAN storage, disk deduplication significantly decreases the factual disk foot print on the SAN itself.

The third point is a bit harder to debate, although the ‘in use’ part is the actual part of the sentence that makes the difference. While Server Core installations in Windows Server 2012 have a bigger disk foot print, a smaller percentage of that code is actually in use when you compare it to Windows Server 2008 R2-based Server Core installations. As I’ve explained in my blogpost Permanent Link to Updating Server Core and switching GUIs, a Server Core installation differs from a full installation by the amount of GUI-related features hardlinked to in the Side by Side store in the C:\Windows\WinSxS folder, which in turn is linked to the C:\Windows\Servicing\Packages folder.

Graphical

The diagrams below illustrate the differences in disk foot print between Server Core and Full installations of Windows Server 2008 R2 and Windows Server 2012:

Comparison of Server Core Disk Foot Print and Attack Surface between Windows Server 2008 R2 and Windows Server 2012

The real impact

Apart from the flexibility Microsoft is giving us to switch between the full Graphical User Interface and more minimal user interfaces, there is some real impact with Microsofts new Server Core strategy. One of the most prominent areas of impact is virtual migrations, whether they are Storage vMotions, Storage Migrations (with System Center Virtual Machine Manager), Live Storage Migrations or Shared Nothing Live Migrations: Migrating the storage for a virtual machine running Server Core will take longer, since there is more disk data to transfer.

The alternative

An alternative way Microsoft could have shaped its new Server Core strategy would be with a ‘net-install’. We see these kinds of installs regularly with Linux flavors, where the base installer is run from a setup/live disk and every add-on component is downloaded from (distributed) repositories on the web. Given the recent certificate collision attacks on the Windows Update functionality, I think it’s a good thing Microsoft decided not to pursue this idea. It will be hard to guarantee the integrity of system files when you need to get these from the web.

What do you think?

Do you think Microsoft did the right thing to hand us the flexibility of switching GUIs in the way they did it, would you go for the alternative or would you fix Server Core in a whole other way?

Updating Server Core and switching GUIs

windows_update_icon-120x120Windows Server 2012 offers new capabilities related to Server Core. As I’ve mentioned before, it is now possible to switch the Graphical User Interface (GUI) mode after initial installation. This new capability allows us to configure a Windows Server system to our needs, using the interface we know and love, and then afterwards make it run in Server Core mode for optimum performance and security.

Applicable updates

One of the configuration steps you might want to perform in the Full Graphical Interface (known as ‘Full installation’) is running Windows Update using the familiar Windows Update interface:

WindowsUpdateWinServer2012

This will install all applicable updates to a Windows Server, including updates for the Metro Start Screen and Internet Explorer. However, when you don’t intend to use the server as a Terminal Server and intend to convert it to a ‘MinShell’ or ‘Server Core’ installation, you might think these updates are of no use.

You may opt not to run Windows Update when in Full Installation, and run sconfig.cmd after converting the server to a more optimum GUI mode and install the applicable Windows updates from the command line then. This approach has a downside, though. If you need to switch back to a full installation or ‘MinShell’ installation, the system would be vulnerable immediately after the required reboot.

For instance, if you need to change the binding order of network interface cards (NICs) and convert the box back, because it’s so darn easy in the graphical interface, then, you would miss updates for every component introduced, since the last Service Pack.

So, updating in the Full Installation initially isn’t such a bad idea when you’re getting started with Server Core in Windows Server 2012. I would even recommend it, if you’ve not been using Server Core in Windows Server 2008 or Windows Server 2008 R2.

Disk space penalties

Luckily, when you run Windows Update, the penalty in disk space is minimal.

As you might be aware, since switching GUIs in Windows Server 2012 does not require the installation media, the bits for all three GUI modes are already on the disk.

Under the hood, when you apply Windows updates to Windows Server 2012, you update the files in the Side by Side store in the C:\Windows\WinSxS folder, which in turn is linked to the C:\Windows\Servicing\Packages folder.

Switching GUIs and adding/removing Server Roles and Features simply enables and disables hard links to files in the Side by Side store. Updating in Windows Server 2012 involves updating the files in the Side by Side store and, therefore, updates the files in use through these hard links.

This is also the reason why switching GUI modes in Windows Server 2012 doesn’t free up the amounts of disk space we’re used to when comparing Server Core installations to Full installations in Windows Server 2008 and Windows Server 2008 R2. A vanilla Server Core Installation takes up 9 GBs of hard disk space, where a vanilla Full Installation fills up 12 GBs of hard disk space with data.

Freeing up disk space now, more than ever, involves removing the installation files for GUI modes, Server Roles and Server Features. More information on this process is available here. Since this limits the possibilities for the Windows Server installation to perform tasks and provide services in the network, this is not something to take lightly. Of course, when configuring highly customized Windows Server installations you might, if you need security and/or performance and disk space is of the essence.

Concluding

One area of Server Core you don’t have to be concerned with when switching the Graphical User Interface (GUI) in Windows Server 2012 is Windows Updates.

Microsoft has created a delicate balance where new Server Core admins can enjoy updated systems by simply performing maintenance tasks in Full installation mode, while also enabling more seasoned Server Core admins to tweak the box further in terms of used disk space.

An issue exists with Server Core in Windows Server “8” Beta

Proceed with cautionLast week, Microsoft released the long-awaited beta build of the next version of Windows Server. With build number 8250 and the beta moniker proudly displayed, we’ve entered a period of stable Windows Server “8” pre-release testing and down to earth information from our Redmondian friends.

After my last post on changing Windows Server GUIs in Windows Server 8, you might be eager to test this feature and convert Server Core, Features on Demand and Full installations after installation.

In the beta build, however, an issue exists, that you might need to be aware of.
The Windows Server “8” Beta Release Notes state:

If you convert a server that was installed with the Server Core installation option during initial setup to the Server with a GUI option, Windows Explorer will not be pinned to the desktop taskbar, and the Start screen will not contain a Desktop tile. This issue does not occur if you choose the Server with a GUI option during setup, convert to a Server Core installation, and then convert back.

To correct this, manually create the shortcuts and tiles by searching for a program on the Start screen. Type its name until its tile appears, and then right-click its tile and choose Pin to taskbar or Pin to Start. To return to the desktop, on the Start screen, type desktop and then click the Desktop tile.

Of course, this is just a minor issue, but, nonetheless, an issue you might want to know about. I’m sure this issue will get fixed soon.

Switching between GUI modes in Windows Server 8

This post covers a pre-release product and was written in February 2012. The actual product may not reflect the behavior, specifications or intentions found in this post. Use with caution.

ConfigureA couple of months ago, I wrote about the new Server Core and Features on Demand options in Windows Server 8. Today I’ll show you how to switch between the Server Core mode and the Full Installation.

The way you’d use the commands below is to test and deploy your Windows Servers. Remember “Server Core is the preferred deployment configuration.”, but not all software and agents (anti-malware, management, UPS, backup, monitoring, etc.) are ready for a Windows installation with minimal Graphical User Interface (GUI). Starting with Windows Server 8, you can switch from a Full Installation to a Server Core installation after installation. Also, you can switch back in case you forgot to adjust a setting that is only available in the Full GUI.

PowerShell, of course…

It should come as no surprise the commands to switch between Server Core, Features on Demand and Full Installation are available as PowerShell cmdlets. PowerShell has been a Common Engineering Criteria since 2009 and all products and technologies should be used with PowerShell. A positive side effect of having PowerShell commands is you can run these commands with a remote code block on any or all Windows Servers in your Server farm.

The cmdlets are part of the DISM PowerShell Module, so every time you’d like to switch between GUI modes, you need to import the module for the cmdlets to be available.

More a traditionalist?

You can also use the more traditional Deployment Image Servicing and Management tool, known within Windows as dism.exe.

One of the things you should be aware of, is that when you use dism.exe you will need to watch the case of your commands.

  

Switching

 
mobsyncBasically, Microsoft has made both the minimalistic GUI and the Full GUI features in Windows Server 8. This means, the commands for switching between the three GUI modes are similar to adding a Server Role or Server Feature on Windows Server 2008 and Windows Server 2008 R2.

From a Full Installation to Server Core

To switch from a Full Installation to the Features on Demand installation option, choose between the following commands:

     Import-Module Dism
     
      Disable-Feature –online –Featurename ServerCore-FullServer

or

    Dism /online /disable-feature /featurename:ServerCore-FullServer

Afterwards, reboot.

From Server Core to a Full Installation

To switch from a Server Core installation to a Full Installation, requires a bit more work, but is more or less identical:

     Import-Module Dism
    
     Enable-Feature –online -Featurename ServerCore-FullServer,
     Server-Gui-Shell,Server-Gui-Mgmt

or

     Dism /online /enable-feature /featurename:ServerCore-FullServer
    
/featurename:Server-Gui-Shell /featurename:Server-Gui-Mgmt

Afterwards, reboot.

Server Core and Features on Demand in Windows Server 8

This post covers a pre-release product and was written in September 2011. The actual product may not reflect the behavior, specifications or intentions found in this post. Use with caution.

Microsoft showed off Windows Server 8 at the second day of the //Build/ conference last week. In the session named SAC-416T, Andrew Mason (Principal Group Program Manager for Server Core) and Jeffrey Snover (Distinguished Engineer and Lead Architect of Windows Server) introduced the plans with user interface options in Windows 8.

A little bit of recent history…

Whereas Windows Server 2008 and Windows Server 2008 R2 offer the Server Core installation option, to minimize the burden of Graphical User Interfaces (GUIs), according to Microsoft, this was an ideal situation.

Windows Server 2008

As you might remember, Server Core was introduced as an installation option for Windows Server in Windows Server 2008. As a systems administrator you could choose this option at installation and you needed to stick with your choice. This choice meant you had trouble installing applications (like UPS management, backup and antivirus tools) and management was spotty without PowerShell. Also, one of the places where security mattered most could not be addressed within Server Core: Servers running dynamic (ASP.Net based) websites.

Windows Server 2008 R2

With the release Microsoft improved the Server Core installation option significantly. Now you could make most ASP.Net-based websites work on server Core, roughly 230 PowerShell cmdlets were introduced and most producers of management, UPS and antivirus products had awoken to the idea of Windows Server without Windows.

Windows Server 8

With Windows Server 8, Microsoft ups the game. Windows PowerShell now boosts a tenfold more cmdlets. An installation option was deemed insufficient, so the option to switch between the Server Core and Full installation gets introduced. Furthermore, Microsoft will introduce a new flavor between the Server Core installation and the Full installation. This is called the ‘Features on Demand’ option.

These three flavors can already be found when installing the Windows Server 8 Developer Preview (build 8102):

image

This screen during the Windows server setup now loses a lot of importance, since you can switch between the three flavors after the Operating System is installed.

Differences between the three interface options

The differences between these three flavors is described in the following table:

Server Core Installation

Features on Demand

Full Installation

Windows Core

o

o

o

Windows PowerShell

o

o

o

.Net Framework 4

o

o

o

Server Manager

o

o

Microsoft Management Consoles

o

o

A subset of Control Panel Applets

o

All Control Panel Applets

o

Windows Help

o

Windows Explorer

o

Internet Explorer

o

Guidance

Andrew and Jeffrey delivered the message ‘Server Core is the preferred deployment configuration’ strongly. This single sentence even received it’s own PowerPoint slide to illustrate the point. A Server Core installation requires the least amount of resources, time and patches of all Windows Server installation options.

But no longer, will you need to deploy your server as a Server Core installation. From Windows Server 8, you will be able to install Windows Server either as a Full Installation or Features on Demand Installation and when done trim down the Windows Server installation to a Server Core installation, where possible.

If all your agents and applications support Server Core and you don’t need any of the MMCs or Control Panel Applets, or you can reproduce your advanced settings through the registry, APIs, Remotely or through WS-Management, you can install Server Core from the start, offering you a superb deployment experience with the least amount of deployment traffic.

Concluding

Microsoft unfolded a strategic view on the interface options in Windows Server 8. You can now choose between a Server Core installation, a Features on Demand Installation and a Full Installation, each offering more Graphical User Interface elements.

No longer do you need to make this choice at the installation of the Windows Server Operating System. You can switch between the three interface options after installation, offering huge flexibility and security in the long run.

Further reading

Windows Server 8 apps must run without a GUI – learn more now

Microsoft Unveils Windows Server 8
Windows Server 8 will bring us this!
10 best new features of Windows Server 8
Windows Server 8: Now with added VMware and Unix
Windows Server 8 should be full of surprises
Microsoft provides more details about Windows Server 8