Obtaining an Object Identifier from Microsoft
To extend the Active Directory schema successfully you can obtain a root OID from a script shown below. The OIDs generated from the script are unique; they are mapped from a unique GUID. Please read the best practices carefully as poorly handled OIDs can result in data loss.
For instructions on obtaining a link-Id from Microsoft, please visit the Linked Attributes topic.
After You Have Obtained a Base OID
Once you have a base OID, be careful when deciding how the OIDs should be divided into categories, because these OIDs are contained in the prefix table and are part of the DC replication data. It is recommended that no more than two OID categories be created.
You can create subsequent OIDs for new schema classes and attributes by appending digits to the OID in the form of OID.X, where X may be any number that you choose. A common schema extension generally uses the following structure:
If your assigned base OID was 1.2.840.113556.1.8000.999999, you might create categories as follows.
|OID base value||Description|
The first class would have the OID 1.2.840.113556.1.8000.999999.1.1, the second class would have the OID 1.2.840.113556.1.8000.999999.1.2, and so on.
The first attribute's OID would be 1.2.840.113556.1.8000.999999.2.1, the second attribute's OID would be 1.2.840.113556.1.8000.999999.2.2, and so on.
' oidgen.vbs ' ' THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED ' OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR ' FITNESS FOR A PARTICULAR PURPOSE. ' ' Copyright (c) Microsoft Corporation. All rights reserved ' Improvements made by Ryein C. Goddard ' ' This script is not supported under any Microsoft standard support program or service. ' The script is provided AS IS without warranty of any kind. Microsoft further disclaims all ' implied warranties including, without limitation, any implied warranties of merchantability ' or of fitness for a particular purpose. The entire risk arising out of the use or performance ' of the scripts and documentation remains with you. In no event shall Microsoft, its authors, ' or anyone else involved in the creation, production, or delivery of the script be liable for ' any damages whatsoever (including, without limitation, damages for loss of business profits, ' business interruption, loss of business information, or other pecuniary loss) arising out of ' the use of or inability to use the script or documentation, even if Microsoft has been advised ' of the possibility of such damages. ' ---------------------------------------------------------------------- Function GenerateOID() 'Initializing Variables Dim guidString, oidPrefix Dim guidPart0, guidPart1, guidPart2, guidPart3, guidPart4, guidPart5, guidPart6 Dim oidPart0, oidPart1, oidPart2, oidPart3, oidPart4, oidPart5, oidPart6 On Error Resume Next 'Generate GUID Set TypeLib = CreateObject("Scriptlet.TypeLib") guidString = TypeLib.Guid 'If no network card is available on the machine then generating GUID can result with an error. If Err.Number <> 0 Then Wscript.Echo "ERROR: Guid could not be generated, please ensure machine has a network card." Err.Clear WScript.Quit End If 'Stop Error Resume Next On Error GoTo 0 'The Microsoft OID Prefix used for the automated OID Generator oidPrefix = "1.2.840.113556.1.8000.2554" 'Split GUID into 6 hexadecimal numbers guidPart0 = Trim(Mid(guidString, 2, 4)) guidPart1 = Trim(Mid(guidString, 6, 4)) guidPart2 = Trim(Mid(guidString, 11, 4)) guidPart3 = Trim(Mid(guidString, 16, 4)) guidPart4 = Trim(Mid(guidString, 21, 4)) guidPart5 = Trim(Mid(guidString, 26, 6)) guidPart6 = Trim(Mid(guidString, 32, 6)) 'Convert the hexadecimal to decimal oidPart0 = CLng("&H" & guidPart0) oidPart1 = CLng("&H" & guidPart1) oidPart2 = CLng("&H" & guidPart2) oidPart3 = CLng("&H" & guidPart3) oidPart4 = CLng("&H" & guidPart4) oidPart5 = CLng("&H" & guidPart5) oidPart6 = CLng("&H" & guidPart6) 'Concatenate all the generated OIDs together with the assigned Microsoft prefix and return GenerateOID = oidPrefix & "." & oidPart0 & "." & oidPart1 & "." & oidPart2 & "." & oidPart3 & _ "." & oidPart4 & "." & oidPart5 & "." & oidPart6 End Function Set oShell = WScript.CreateObject ("WScript.Shell") oShell.run "cmd /c Regsvr32 Schmmgmt.dll" Set objFSO=CreateObject("Scripting.FileSystemObject") outFile="C:\Users\Administrator\Desktop\oidInfo.txt" Set objFile = objFSO.CreateTextFile(outFile,True) 'Output the resulted OID with best practice info oidText = "Your root OID is: " & VBCRLF & GenerateOID & VBCRLF & VBCRLF & VBCRLF & _ "This prefix should be used to name your schema attributes and classes. For example: " & _ "if your prefix is ""Microsoft"", you should name schema elements like ""microsoft-Employee-ShoeSize"". " & _ "For more information on the prefix, view the Schema Naming Rules in the server " & _ "Application Specification (http://www.microsoft.com/windowsserver2003/partners/isvs/appspec.mspx)." & _ VBCRLF & VBCRLF & _ "You can create subsequent OIDs for new schema classes and attributes by appending a .X to the OID where X may " & _ "be any number that you choose. A common schema extension scheme generally uses the following structure:" & VBCRLF & _ "If your assigned OID was: 1.2.840.113556.1.8000.2554.999999" & VBCRLF & VBCRLF & _ "then classes could be under: 1.2.840.113556.1.8000.2554.999999.1 " & VBCRLF & _ "which makes the first class OID: 1.2.840.113556.1.8000.2554.999999.1.1" & VBCRLF & _ "the second class OID: 1.2.840.113556.1.8000.2554.999999.1.2 etc..." & VBCRLF & VBCRLF & _ "Using this example attributes could be under: 1.2.840.113556.1.8000.2554.999999.2 " & VBCRLF & _ "which makes the first attribute OID: 1.2.840.113556.1.8000.2554.999999.2.1 " & VBCRLF & _ "the second attribute OID: 1.2.840.113556.1.8000.2554.999999.2.2 etc..." & VBCRLF & VBCRLF & _ "Here are some other useful links regarding AD schema:" & VBCRLF & _ "Understanding AD Schema" & VBCRLF & _ "http://technet2.microsoft.com/WindowsServer/en/Library/b7b5b74f-e6df-42f6-a928-e52979a512011033.mspx " & _ VBCRLF & VBCRLF & _ "Developer documentation on AD Schema:" & VBCRLF & _ "http://msdn2.microsoft.com/en-us/library/ms675085.aspx " & VBCRLF & VBCRLF & _ "Extending the Schema" & VBCRLF & _ "http://msdn2.microsoft.com/en-us/library/ms676900.aspx " & VBCRLF & VBCRLF & _ "Step-by-Step Guide to Using Active Directory Schema and Display Specifiers " & VBCRLF & _ "http://www.microsoft.com/technet/prodtechnol/windows2000serv/technologies/activedirectory/howto/adschema.mspx " & _ VBCRLF & VBCRLF & _ "Troubleshooting AD Schema " & VBCR & _ "http://technet2.microsoft.com/WindowsServer/en/Library/6008f7bf-80de-4fc0-ae3e-51eda0d7ab651033.mspx " & _ VBCRLF & VBCRLF objFile.Write oidText objFile.Close