Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
What Is WMI? • WMI is the core management-enabling technology built into Windows 2000, Windows XP, and the Windows Server 2003 family of operating systems. • Based on industry standards overseen by the Distributed Management Task Force (DMTF) • Almost all—Windows resources can be accessed, configured, managed, and monitored
Windows 2003/XP/2000 systems management • retrieve performance data • Manage: • event logs • file systems • printers • processes • registry settings • scheduler, security • services • Shares • ….
Network management • You can create WMI-based scripts to manage network services such as: • DNS • DHCP • SNMP-enabled devices.
Real-time health monitoring • Using WMI event subscriptions, you can write scripts to: • monitor and respond to event log entries as they occur, • file system and registry modifications • other real-time operating system changes.
Windows .NET Enterprise Server management • You can write scripts to manage • Microsoft® Application Center • Operations Manager • Systems Management Server • Internet Information Server • Exchange Server • SQL Server
Example 1 Set refWMI = GetObject("winMgmts:") Set colDrives = refWMI.ExecQuery( _ "SELECT * FROM Win32_LogicalDisk") For Each refDrive In colDrives WScript.Echo _ "Device '" & refDrive.DeviceID & "' has " _ & refDrive.FreeSpace & " bytes free" Next
Example 2 Set refWMI = GetObject("winMgmts:") Set colDrives = refWMI.ExecQuery( _ "SELECT * FROM Win32_LogicalDisk WHERE DriveType='3'") For Each refDrive In colDrives WScript.Echo _ "Device '" & refDrive.DeviceID & "' has " _ & (Round(refDrive.FreeSpace/1048576)) & "Mb free" Next
Remote computer strComputer = “compname" Set wbemServices = _ GetObject("winmgmts:\\" & strComputer) Set wbemObjectSet = wbemServices.InstancesOf( _ "Win32_LogicalMemoryConfiguration") For Each wbemObject In wbemObjectSet WScript.Echo "Total Physical Memory (kb): " & _ wbemObject.TotalPhysicalMemory Next
WMI Architecture The key to WMI’s power is that it enforces separation between Providers who offer a WMI interface and Applications who use that interface. There is only one point of contact between them, namely the CIM Object Manager.
Providers • Typically created by device driver writers, or developers who want to provide WMI access to their programs. • Almost invariably written in C++ • Specify WMI classes and their implementations
Applications • Created by developers or sysadmins who want to access WMI data • Typically written in C++ or VB or VBScript or JScript • Specify instructions for accessing WMI class instances (objects), reading their Properties and executing their Methods
The CIM Object Manager • Keeps a record of what WMI classes are available on a system and which providers are responsible for servicing them. • Retrieves WMI objects or classes on behalf of an application, talking to Providers as necessary.
Three ways to retrieve an object: • Ask for it specifically by name • Ask what objects of a certain type are “in stock” • Browse the Repository
Retrieve an object by name Method One – using SWbemServices.Get(): Set refWMI = GetObject(“winMgmts:”) Set refDir = refWMI.Get(“Win32_Directory.Name=‘c:\’”) Method Two – a more compact version: Set refDir = GetObject(“winMgmts:”).Get( _ “Win32_Directory.Name=‘c:\’”) Method Three – directly in a Moniker: Set refDir = GetObject(“winMgmts:Win32_Directory.Name=‘c:\’”)
Anatomy of a Moniker winMgmt:\\mango\root\cimv2:Win32_LogicalDisk.DeviceID=‘c:’
WMI Namespaces • The WMI world is split into namespaces. Namespaces are: • Hierarchically organised • Isolated from each other • When connecting to WMI on a machine, the connection is made to a specific namespace.
Retrieve objects by type Method One – a data query: Set refWMI = GetObject(“winMgmts:”) Set colDirectories = refWMI.ExecQuery( _ “SELECT * FROM Win32_Directory”) Method Two – retrieve a class and get its instances: Set refWMI = GetObject(“winMgmts:”) Set refDirectoryClass = refWMI.Get(“win32_Directory”) Set colDirectories = refDirectoryClass.Instances_() Method Three – a more concise version: Set colDirectories = _ GetObject(“winMgmts:Win32_Directory”).Instances_()
Browse the repository List all classes: Set refWMI = GetObject(“winMgmts:”) Set colClasses = refWMI.ExecQuery( _ “SELECT * FROM meta_class”) For Each refClass In colClasses WScript.Echo refClass.Path_.Class Next Set colClasses = Nothing Set refWMI = Nothing
Listing installed Products Option Explicit Dim refWMI Dim colInstProducts Dim refProduct 'connect to WMI and retrieve collection of Win32_Products Set refWMI = GetObject("winmgmts:") If Err <> 0 Then WScript.Echo "Could not connect to WMI" WScript.Quit End If Set colInstProducts = refWMI.InstancesOf("Win32_Product") 'Loop through Products adding report entries For Each refProduct in colInstProducts WScript.echo refProduct.Name & " (Version: " & refProduct.Version & ")" & chr(13) Next Set ColInstProducts = Nothing Set refWMI = Nothing
WMI Architecture • The WMI architecture consists of three primary layers • Managed resources • WMI infrastructure • Consumers
Managed Resources • Windows resources that can be managed using WMI include: • computer system • disks • peripheral devices • event logs • files • folders • file systems • networking components, • operating system subsystems, performance counters, printers, processes, registry settings, security, services, shares, SAM users and groups, Active Directory, Windows Installer, Windows Driver Model (WDM) device drivers ….
WMI Infrastructure • WMI consists of three primary components: • the Common Information Model Object Manager (CIMOM) • the Common Information Model (CIM) repository • providers. • Together, the three WMI components provide the infrastructure through which configuration and management data is defined, exposed, accessed, and retrieved
WMI Providers • WMI providers act as an intermediary between WMI and a managed resource • Providers hide the implementation details on WMI's standards-based, uniform access model • Providers are generally implemented as dynamic link libraries (DLLs) residing in the %SystemRoot%\system32\wbem directory
Active Directory provider • File: dsprov.dll • Namespace: root\directory\ldap • Maps Active Directory objects to WMI
Event Log provider • ntevt.dll • root\cimv2 • Manage Windows event logs, for example, read, backup,clear, copy, delete, monitor, rename, compress, uncompress, and change event logsettings.
Performance Counter provider • wbemperf.dll • root\cimv2 • Provides access to raw performance data.
More providers • Registry provider • SNMP provider • WDM provider • Win32 provider • Windows Installer provider • ……
CIMOM • handles the interaction between consumers and providers • the CIMOM provides the following core services to the WMI infrastructure: • Provider registration • Request routing • Remote access • Security • Query processing • Event processing
CIM Repository • storing the blueprints for managed resources • CIM classes are organized hierarchically • Classes are grouped into namespaces • CIM classes consist of properties and methods
WMI Scripting Library • The WMI scripting library provides the set of automation objects through which scripting languages, such as VBScript, Jscript, and ActiveState's ActivePerl access the WMI infrastructure • The automation objects in the WMI scripting library provide a consistent and uniform scripting model for the WMI infrastructure
WMI Consumers • Consumers are the top layer. A consumer is a script, enterprise management application, Web-based application, or other administrative tool, that accesses and controls management information available through the WMI infrastructure
Some tools • Wbemtest • Scriptomatic • WMI sdk tools
Namespaces • Namespaces are the partitioning mechanism employed by the CIM and control the scope and visibility of managed-resource class definitions. • Each namespace in the CIM contains a logical group of related classes representing a specific technology or area of management. • All classes within a namespace must have a unique class name • Classes in one namespace cannot be derived from classes in another namespace, which is why you'll find identical system, core, and common classes defined in multiple namespaces
Namespace Usage • No namespace: strComputer = "." Set wbemServices = GetObject("winmgmts:\\" & strComputer) • Default namespace registry key: • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WBEM\Scripting\Default Namespace • Change namespace: strComputer = "." Set wbemServices = GetObject("winmgmts:\\" & strComputer & "\root\cimv2")
Retrieving the default namespace strComputer = "." Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\root\cimv2") Set colWMISettings = objWMIService.InstancesOf("Win32_WMISetting") For Each objWMISetting in colWMISettings Wscript.Echo "Default namespace for scripting: " & _ objWMISetting.ASPScriptDefaultNamespace Next
Setting the default namespace strComputer = "." Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\root\cimv2") Set colWMISettings = objWMIService.InstancesOf("Win32_WMISetting") For Each objWMISetting in colWMISettings objWMISetting.ASPScriptDefaultNamespace = "root\cimv2" objWMISetting.Put_ Next
Listing Namespaces strComputer = "." Set objServices = GetObject("winmgmts:\\" & strComputer & "\root") Set colNameSpaces = objServices.InstancesOf("__NAMESPACE") For Each objNameSpace In colNameSpaces WScript.Echo objNameSpace.Name Next
Retrieving all CIM namespaces strComputer = "." Call EnumNameSpaces("root") Sub EnumNameSpaces(strNameSpace) WScript.Echo strNameSpace Set objWMIService = GetObject("winmgmts:\\" & strComputer & "\" & strNameSpace) Set colNameSpaces = objWMIService.InstancesOf("__NAMESPACE") For Each objNameSpace In colNameSpaces Call EnumNameSpaces(strNameSpace & "\" & objNameSpace.Name) Next End Sub