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How to create a SCOM group from an Active Directory Computer Group

 

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There have been a bunch of examples of this published over the years.  Some of them worked well, but I was never happy with many of them as they were often vbscript based, hard to troubleshoot, and required lots of editing each time you wanted to reuse them.  Many were often error prone, and didn’t work if the AD group contained computers that didn’t exist in SCOM, as SCOM will reject the entire discovery data payload in that case.

If you too were looking for a reliable and easy way to do this, well, look no further!  I have created an MP Fragment in my fragment library for this:

https://gallery.technet.microsoft.com/SCOM-Management-Pack-VSAE-2c506737

 

This MP Fragment will make creating SCOM groups of Windows Computers from Active Directory groups super easy!  This is a nice way to “delegate” the ability for end users to control what servers will appear in their scopes, as they often have the ability to easily add and remove computers from their AD groups, but they do not have access to SCOM Group memberships.

I am going to demonstrate using Silect MP Author Pro to reuse this Fragment, and you can also easily use Visual Studio with VSAE.  If you’d like to read more on either of those, see:

https://kevinholman.com/2016/06/04/authoring-management-packs-the-fast-and-easy-way-using-visual-studio/

https://kevinholman.com/2017/03/22/management-pack-authoring-the-really-fast-and-easy-way-using-silect-mp-author-and-fragments/

 

In Silect MP Author Pro – create a new, empty management pack, and select “Import Fragment”

 

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Browse the fragment and choose:  Class.Group.ADGroupWindowsComputers.mpx

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We need to simply input the values here, such as:

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Click “Import

Silect MP Author Pro will automagically handle the references for you, so just say “Yes” on the popup:

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That’s IT!   Surprised smile

 

Save it, and deploy it!

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If you look in SCOM after a few minutes – you should see your group:

 

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The rule to populate it runs once a day by default, but it will run immediately upon import.  Look for event ID 7500 in the OpsMgr event log on the Management Server that hosts your All Management Servers Resource Pool object

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Once you see these events and no errors in them – you can view group membership in SCOM:

 

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So easy.  And you don’t have to know anything about XML, or even Management Packs to do it!

Using Visual Studio with VSAE works exactly the same way – you simply have to do a manual Find/Replace for each item.  See the VSAE method in the link above.

 

Want to dig deeper into how this is put together?  Read on:

The MP we generate is very basic.  There is a Class (the Group definition) a Relationship (the Group contains Windows Computers) and a discovery (queries AD and discovers the relationship to the existing Windows Computers in SCOM)

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The script is below:

We basically connect to AD, find the group by name, query to get members, look the membership up and see if they exist in SCOM, if they do, add them to the group.

We will log events along the way to help in troubleshooting if anything doesn’t work, and record the completion and total script runtime, like all my SCOM scripts.

#================================================================================= # Group Population script based on AD group membership # # Kevin Holman # v1.6 #================================================================================= param($SourceID, $ManagedEntityID, $ADGroup, $LDAPSearchPath) # Manual Testing section - put stuff here for manually testing script - typically parameters: #================================================================================= # $SourceId = '{00000000-0000-0000-0000-000000000000}' # $ManagedEntityId = '{00000000-0000-0000-0000-000000000000}' # $ADGroup = "SCOM Computers Group" # $LDAPSearchPath = "LDAP://DC=opsmgr,DC=net" #================================================================================= # Constants section - modify stuff here: #================================================================================= # Assign script name variable for use in event logging $ScriptName = "##CompanyID##.##AppName##.##GroupNameNoSpaces##.ADBased.Group.Discovery.ps1" $EventID = "7500" #================================================================================= # Starting Script section - All scripts get this #================================================================================= # Gather the start time of the script $StartTime = Get-Date # Load MOMScript API $momapi = New-Object -comObject MOM.ScriptAPI # Load SCOM Discovery module $DiscoveryData = $momapi.CreateDiscoveryData(0, $SourceId, $ManagedEntityId) #Set variables to be used in logging events $whoami = whoami #Log script event that we are starting task $momapi.LogScriptEvent($ScriptName,$EventID,0,"`n Script is starting. `n Running as ($whoami).") #================================================================================= # Connect to local SCOM Management Group Section #================================================================================= # Clear any previous errors $Error.Clear() # Import the OperationsManager module and connect to the management group $SCOMPowerShellKey = "HKLM:\SOFTWARE\Microsoft\System Center Operations Manager\12\Setup\Powershell\V2" $SCOMModulePath = Join-Path (Get-ItemProperty $SCOMPowerShellKey).InstallDirectory "OperationsManager" Import-module $SCOMModulePath New-DefaultManagementGroupConnection "localhost" IF ($Error) { $momapi.LogScriptEvent($ScriptName,$EventID,1,"`n FATAL ERROR: Failure loading OperationsManager module or unable to connect to the management server. `n Terminating script. `n Error is: ($Error).") EXIT } #================================================================================= # Begin MAIN script section #================================================================================= #Log event for captured parameters $momapi.LogScriptEvent($ScriptName,$EventID,0,"`n ADGroup: ($ADGroup) `n LDAP search path: ($LDAPSearchPath).") # Health Service class section # We need this list of SCOM agents, so we can only submit discovery data for a Healthservice in SCOM otherwise SCOM will reject the discovery data, and this will clean up deleted stale Windows Computer objects that will remain until the next discovery # Clear any previous errors $Error.Clear() # Get all instances of a existing Health Service class $HS = Get-SCOMClass -Name "Microsoft.SystemCenter.Healthservice" | Get-SCOMClassInstance $HSNames = $HS.DisplayName $HSCount = $HSNames.count IF($Error) { $momapi.LogScriptEvent($ScriptName,$EventID,1, "`n FATAL ERROR: Unable to gather Healthservice instances from SCOM. `n Error is: $Error") EXIT } ELSE { $momapi.LogScriptEvent($ScriptName,$EventID,0, "`n Get all Health Service Objects from SCOM has completed. `n Returned ($HSCount) Health Service Objects from SCOM.") } # END Health Service class section # Connect to AD using LDAP search to find the DN for the Group $Searcher = New-Object DirectoryServices.DirectorySearcher $Searcher.Filter = '(&(objectCategory=group)(cn=' + $ADGroup + '))' $Searcher.SearchRoot = $LDAPSearchPath $Group = $Searcher.FindAll() IF ($Error) { $momapi.LogScriptEvent($ScriptName,$EventID,1,"`n FATAL ERROR: Failure getting data from AD for ($ADGroup). `n Terminating script. `n Error is: ($Error).") EXIT } $GroupDN = @() # Now that we have the group object, trim to get the DN in order to search for members $GroupDN = $Group.path.TrimStart("LDAP://") #If we found the group in AD by the DisplayName log a success event otherwise log error IF ($GroupDN) { $momapi.LogScriptEvent($ScriptName,$EventID,0,"`n Successfully found group in AD. `n ADGroup: ($ADGroup) `n GroupDN: ($GroupDN).") } ELSE { $momapi.LogScriptEvent($ScriptName,$EventID,1,"`n FATAL ERROR: Did not find group in AD: ($ADGroup) using ($LDAPSearchPath). `n Terminating script.") EXIT } # Search for members of the group $Searcher = New-Object DirectoryServices.DirectorySearcher $Searcher.Filter = '(&(objectCategory=computer)(memberOf=' + $GroupDN + '))' $ADComputerObjects = $Searcher.FindAll() $ADComputerObjectsCount = $ADComputerObjects.Count If ($ADComputerObjectsCount -gt 0) { $momapi.LogScriptEvent($ScriptName,$EventID,0,"`n Successfully found ($ADComputerObjectsCount) members in the group. `n ADGroup: ($ADGroup) `n GroupDN: ($GroupDN).") } Else { $momapi.LogScriptEvent($ScriptName,$EventID,1, "`n FATAL ERROR: Did not find any members in the AD group. `n ADGroup: ($ADGroup) `n GroupDN: ($GroupDN). `n Terminating script.") EXIT } # Set namelist array to empty $NameList = @() # Loop through each computer object and build an array of FQDN hostnames FOREACH ($ADComputerObject in $ADComputerObjects) { #Get the DNS Hostname property from AD [string]$DNSComputerName = $ADComputerObject.Properties.dnshostname #Only add the name to the array if the DNSHostname property exists in AD IF ($DNSComputerName) { $NameList += $DNSComputerName } } $NameListCount = $NameList.Count IF ($NameListCount -ge 1) { $momapi.LogScriptEvent($ScriptName,$EventID,0,"`n Successfully found ($NameListCount) DNS Names from the original ($ADComputerObjectsCount) members in the group. `n ADGroup: ($ADGroup) `n GroupDN: ($GroupDN).") } ELSE { $momapi.LogScriptEvent($ScriptName,$EventID,1,"`n FATAL ERROR: There was an error getting DNS Host Names or none were found for members of the group. `n Group objects count: ($ADComputerObjectsCount). `n ADGroup: ($ADGroup) `n GroupDN: ($GroupDN). `n Terminating script.") EXIT } #Discovery Section #Set the group instance we will discover members of $GroupInstance = $DiscoveryData.CreateClassInstance("$MPElement[Name='##CompanyID##.##AppName##.##GroupNameNoSpaces##.ADBased.Group']$") # Loop through each SCOM computer and add a group membership containment relationship to the discovery data $i=0; FOREACH ($Name in $NameList) { #Check to make sure the name we got from AD exists as a Healthservice in this Management Group IF ($Name -in $HSNames) { $i = $i+1 $ServerInstance = $DiscoveryData.CreateClassInstance("$MPElement[Name='Windows!Microsoft.Windows.Computer']$") $ServerInstance.AddProperty("$MPElement[Name='Windows!Microsoft.Windows.Computer']/PrincipalName$", $Name) $RelationshipInstance = $DiscoveryData.CreateRelationshipInstance("$MPElement[Name='##CompanyID##.##AppName##.##GroupNameNoSpaces##.ADBased.Group.Contains.Windows.Computers']$") $RelationshipInstance.Source = $GroupInstance $RelationshipInstance.Target = $ServerInstance $DiscoveryData.AddInstance($RelationshipInstance) } } IF ($i -ge 1) { $momapi.LogScriptEvent($ScriptName,$EventID,0,"`n Successfully found ($i) Computers in SCOM from the original ($NameListCount) DNS names pulled from the group. `n ADGroup: ($ADGroup) `n GroupDN: ($GroupDN).") } ELSE { $momapi.LogScriptEvent($ScriptName,$EventID,1,"`n FATAL ERROR: No computers in SCOM were found matching the ($NameListCount) DNS names pulled from the group. `n Group objects: ($ADComputerObjectsCount). `n ADGroup: ($ADGroup) `n GroupDN: ($GroupDN). `n Terminating script.") EXIT } # Return Discovery Items Normally $DiscoveryData # Return Discovery Bag to the command line for testing (does not work from ISE) # $momapi.Return($DiscoveryData) #================================================================================= # End MAIN script section # End of script section #================================================================================= #Log an event for script ending and total execution time. $EndTime = Get-Date $ScriptTime = ($EndTime - $StartTime).TotalSeconds $momapi.LogScriptEvent($ScriptName,$EventID,0,"`n Script Ending. `n Script Runtime: ($ScriptTime) seconds.") #=================================================================================

 

Key recommendations:

1.  Don’t run your frequency <intervalseconds> too often.  If updating the group once a day is ok, leave it at the default.  If you need it more frequent, that’s fine, just remember it’s a script, and all scripts running on the management servers have an impact on the overall load, plus we are submitting discovery data about relationships each time, and searching through AD.

2.  The default timeout is set to 5 minutes.  If you cannot complete this in less, something is WRONG and it most likely will be how long it takes to find the group in AD.  If that is true for you, you need to optimize the section on querying AD and LDAP search path.

3.  If you have a lot of AD based SCOM groups, consider adding a staggered sync time to each discovery, so they don’t all run at the same time, or on the same interval.

9 Comments

  1. Peter Commander

    Kevin,
    Love this fragment, and use it often! Thanks. One question: we monitor multiple domains (untrusted) in a single SCOM Management Group; and this script runs under the default SCOM credentials. There are alternate action accounts defined in the MG to access the other domains; is there a way to run the script with different credentials / action account?

    • Kevin Holman

      You cannot run a workflow in SCOM using an untrusted RunAs account. When you configure RunAs, we create a monitoringhost.exe process AS a specific user credential, and then run all workflows under that process. An untrusted account cannot log on or be authenticated. To solve your issue, you’d have to come up with some way to have an agent or GW in the untrusted forest run the AD queries, then have a way to use that output as the group population datasource.

  2. Peter Commander

    Kevin,
    Thanks for the response… drat, I was afraid of that. Looks like the gateway is the way to go… another challenge ahead!
    Peter

  3. david

    Hi Kevin, I can created a MP for find AD computers and the MP runs without errors and state we found this amount however I got no group members into the SCOM group – do you know what might be causing this issue ?

    • Kevin Holman

      I’d look at the events that the script logs, then look for other events about SCOM rejecting the discovery data.

  4. david

    Thanks Kevin, looks like the powershell is timing out – so we are tightening the LDAP string as we was going to the top level domain

  5. Steve

    Hi Kevin, I’ve used this method for creating a group, and it initially creates and populates the group as expected. The problem I’m having is when the source – AD group/file/whatever – changes, the group membership doesn’t change. Any thoughts what might be happening there? Cheers, Steve

    • Kevin Holman

      If you look at the events logged by the script – does it show what should be discovered correctly? If so – do you see events on the same SCOM management server rejecting the discovery data?

      • Steve

        I didn’t include the logging in the script. I know, an oversight on my part. I’ve tested the script externally to the MP and it’s definitely find the correct objects to add to the group. There were no events on the management server indicating an issue with the discovery – I know the events you are referring to there.

        Now interestingly, in an attempt to make troubleshooting easier, I reimported the MP with the only change being the interval the script runs – down from once a day to every 10 minutes. A few minutes after this the new object was added to the group. The change to the AD group happened 3 days ago, so the script would definitely have run in that time.

        I’ll add logging to the script and see if I can replicate the issue.

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