{"id":2479,"date":"2013-12-05T00:01:00","date_gmt":"2013-12-05T00:01:00","guid":{"rendered":"https:\/\/blogs.technet.microsoft.com\/heyscriptingguy\/2013\/12\/05\/getting-started-with-powershell-the-basics-of-wmi\/"},"modified":"2013-12-05T00:01:00","modified_gmt":"2013-12-05T00:01:00","slug":"getting-started-with-powershell-the-basics-of-wmi","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/scripting\/getting-started-with-powershell-the-basics-of-wmi\/","title":{"rendered":"Getting Started with PowerShell: The Basics of WMI"},"content":{"rendered":"

Summary<\/strong>: Microsoft Scripting Guy, Ed Wilson, talks about querying WMI in this excerpt of his book, Windows PowerShell 3.0 First Steps.<\/p>\n

Microsoft Scripting Guy, Ed Wilson, is here. Today I have the last excerpt from my new Microsoft Press book, Windows PowerShell 3.0 First Steps<\/a>.<\/p>\n

\"Image<\/a><\/p>\n

In most situations, when you use WMI, you are performing some sort of query. Even when you are going to set a particular property, you still need to execute a query to return a dataset that enables you to perform the configuration. (A dataset includes the data that come back to you as the result of a query, that is, it is a set of data.) There are several steps involved in performing a basic WMI query:<\/p>\n

    \n
  1. Connect to WMI by using the Get-WMIObject<\/strong> <\/strong>cmdlet.<\/li>\n
  2. Specify a valid WMI class name to query.<\/li>\n
  3. Specify a value for the namespace—omit the Namespace<\/strong> parameter to use the default root\\cimv2 namespace.<\/li>\n
  4. Specify a value for the ComputerName<\/strong> <\/em>parameter—omit the ComputerName<\/strong> <\/em>parameter to use the default value of LocalHost<\/strong>.<\/em><\/li>\n<\/ol>\n

    Windows PowerShell makes it easy to query WMI. In fact, at its most basic level, the only thing required is gwmi<\/strong> <\/em>(alias for the Get-WmiObject <\/strong>cmdlet) and the WMI class name. An example of this simple syntax is shown here, along with the associated output:<\/p>\n

    PS C:\\> gwmi win32_bios
    SMBIOSBIOSVersion : BAP6710H.86A.0064.2011.0504.1711
    Manufacturer      : Intel Corp.
    Name              : BIOS Date: 05\/04\/11 17:11:33 Ver: 04.06.04
    SerialNumber      :
    Version           : INTEL  – 1072009<\/p>\n

    However, there are more properties available in the Win32_Bios WMI class than the five displayed in the previous output. The reason for the limited output that is displayed from the command is a custom view of the Win32_Bios class defined in the types.ps1xml file that resides in the Windows PowerShell home directory on your system. The following command uses the Select-String <\/strong>cmdlet to search the Types.ps1xml file to see if there is any reference to the WMI class Win32_Bios.<\/p>\n

    Select-String -Path $pshome\\*.ps1xml -SimpleMatch “Win32_Bios”<\/p>\n

    In the following image, several Select-String <\/strong>commands display results when a special format exists for a particular WMI class. The last query (for the Win32_CurrentTime WMI class) does not return any results, indicating that no special formatting exists for this class.<\/p>\n

    \"Image<\/a><\/p>\n

    The Select-String <\/strong>queries shown in the previous image indicate that there is a special formatting for the Win32_Bios, Win32_DesktopMonitor, and Win32_Service WMI classes. The Types.ps1xml file provides information to Windows PowerShell that tells it how to display a particular WMI class. When an instance of the Win32_Bios WMI class appears, Windows PowerShell uses the DefaultDisplayPropertySet<\/strong> <\/em>configuration to display only five properties. The portion of the Types.ps1xml file that details these five properties is shown here:<\/p>\n

                        <PropertySet>
                            <Name>DefaultDisplayPropertySet<\/Name>
                            <ReferencedProperties>
                                <Name>SMBIOSBIOSVersion<\/Name>
                                <Name>Manufacturer<\/Name>
                                <Name>Name<\/Name>
                                <Name>SerialNumber<\/Name>
                                <Name>Version<\/Name>
                            <\/ReferencedProperties>
                        <\/PropertySet><\/p>\n

    The complete type definition for the Win32_Bios WMI classis shown in following image:<\/p>\n

    \"Image<\/a><\/p>\n

    Special formatting instructions for the Win32_Bios WMI class indicate that there is an alternate property set available—a property set that is in addition to the DefaultDisplayPropertySet<\/strong>. <\/em>This additional property set, named PSStatus<\/strong>, <\/em>contains the four properties in the PropertySet<\/strong> <\/em>shown here:<\/p>\n

                <PropertySet>
                    <Name>PSStatus<\/Name>
                    <ReferencedProperties>
                        <Name>Status<\/Name>
                        <Name>Name<\/Name>
                        <Name>Caption<\/Name>
                        <Name>SMBIOSPresent<\/Name>
                    <\/ReferencedProperties>
                <\/PropertySet><\/p>\n

    Finding the PSStatus<\/strong> <\/em>property set is more than a simple academic exercise, because it can be used directly with Windows PowerShell cmdlets such as Select-Object <\/strong>(select<\/strong> is an alias), Format-List <\/strong>(fl<\/strong> is an alias), <\/strong>or Format-Table <\/strong>(ft<\/strong> is an alias). The following commands illustrate this technique:<\/p>\n

    gwmi win32_bios | select psstatus
    gwmi win32_bios | fl psstatus
    gwmi win32_bios | ft psstatus <\/p>\n

    Unfortunately, you cannot use the alternate property set, PSStatus<\/strong>, to select the properties via the Property<\/strong> <\/em>parameter. Therefore, the following command fails.<\/p>\n

    gwmi win32_bios -Property psstatus<\/p>\n

    That is all there is to using Windows PowerShell to query WMI.  Join me tomorrow when I will have a guest post from Yuri Diogenes, Security Series: Using PowerShell to Enable BYOD—Part 1<\/strong>.<\/p>\n

    I invite you to follow me on Twitter<\/a> and Facebook<\/a>. If you have any questions, send email to me at scripter@microsoft.com<\/a>, or post your questions on the Official Scripting Guys Forum<\/a>. See you tomorrow. Until then, peace.<\/p>\n

    Ed Wilson, Microsoft Scripting Guy<\/strong> <\/p>\n","protected":false},"excerpt":{"rendered":"

    Summary: Microsoft Scripting Guy, Ed Wilson, talks about querying WMI in this excerpt of his book, Windows PowerShell 3.0 First Steps. Microsoft Scripting Guy, Ed Wilson, is here. Today I have the last excerpt from my new Microsoft Press book, Windows PowerShell 3.0 First Steps. In most situations, when you use WMI, you are performing […]<\/p>\n","protected":false},"author":596,"featured_media":87096,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[51,3,4,45],"class_list":["post-2479","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-scripting","tag-getting-started","tag-scripting-guy","tag-scripting-techniques","tag-windows-powershell"],"acf":[],"blog_post_summary":"

    Summary: Microsoft Scripting Guy, Ed Wilson, talks about querying WMI in this excerpt of his book, Windows PowerShell 3.0 First Steps. Microsoft Scripting Guy, Ed Wilson, is here. Today I have the last excerpt from my new Microsoft Press book, Windows PowerShell 3.0 First Steps. In most situations, when you use WMI, you are performing […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts\/2479","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/users\/596"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/comments?post=2479"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts\/2479\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/media\/87096"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/media?parent=2479"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/categories?post=2479"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/tags?post=2479"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}