| Event Information | According to Microsoft :
Cause :
This event is logged While replicating the schema object, a conflict was detected with the following existing attribute.
Resolution :
Restore the directory service from backup media that was created before schema modification
The schema was modified, and the modification corrupted the schema database. To resolve this issue, restore the Active Directory database from backup media that was created at an earlier time than the time when the attribute schema object was modified. Perform this procedure on the computer that is logging the event to be resolved.
To perform this procedure,must have membership in Domain Admins or must have been delegated the appropriate authority.
To restore the Active Directory database from backup media:- Open a command prompt as an administrator. To open a command prompt as an administrator, click Start. In Start Search, type Command Prompt.At the top of the Start menu, right-click Command Prompt, and then click Run as administrator. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Continue.
- Type bcdedit /set safeboot dsrepair, and then press ENTER.
- Restart the domain controller.
- At the Windows logon screen, click Switch User.
- Click Other User.
- Type .\administrator as the user name, type the Directory Services Restore Mode password for the server, and then press ENTER.
- Open a command prompt. To open a command prompt, click Start.In Start Search, type cmd, and then press ENTER.
- At the command prompt, type wbadmin get versions -backuptarget:targetDrive:, and then press ENTER. Substitute the location of the backup that want to restore for targetDrive.
- Identify the version of the backup that want to restore.Must enter this version exactly in the next step.
- Type wbadmin start systemstaterecovery -version:dateTime -backuptarget:targetDrive:-quiet, and then press ENTER. Substitute the version of the backup that want to restore for dateTime and the volume that contains the backup for targetDrive.
- Open a command prompt, type bcdedit /deletevalue safeboot, and then press ENTER.
- After the recovery operation completes, restart the domain controller.
Note : There is no need to attempt an authoritative restore because the schema cannot be restored by using an authoritative restore.
Verify :
To verify that the schema is in a consistent state, complete the procedures:- Ensure that the domain controllers synchronize their directory data by starting Active Directory replication.
- Enable diagnostic logging for the schema.
- Update the schema cache.
- Verify that the schema was updated successfully by using Event Viewer.
To perform these procedures,must have membership in Domain Admins or must have been delegated the appropriate authority.
Start Active Directory replication
To start Active Directory replication:- Open a command prompt as an administrator. To open a command prompt as an administrator, click Start. In Start Search, type Command Prompt. At the top of the Start menu, right-click Command Prompt, and then click Run as administrator.If the User Account Control dialog box appears, confirm that the action it displays is what want, and then click Continue.
- Run the command repadmin /syncall /user:domain\user /pw:password. Substitute the appropriate domain name, user name, and password for domain, user, and password, respectively. The command output indicates whether synchronization started successfully.
Enable diagnostic logging for the schema
To verify a successful update of the schema, can enable diagnostic logging for the schema. When enable diagnostic logging, a schema update produces Event ID 1582 in the Directory Service log of Event Viewer. To enable diagnostic logging for the schema, must edit the registry.
To enable diagnostic logging for the schema:
Caution : Incorrectly editing the registry might severely damage system. Before making changes to the registry, should back up any valued data.- Open Registry Editor. To open Registry Editor, click Start. In Start Search, type regedit, and then press ENTER. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Continue.
- In the registry location HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NTDS\Diagnostics, in the left pane, right-click the 24 DS Schema value, and then click Modify.
- Type 1 or higher (up to 5) for Value data to enable diagnostic logging for the schema. The higher the value, the more information is reported to the Directory Service log.Click OK.
Update the schema cache
To update the schema cache:- Create a file to force a schema cache update using Ldifde.exe. Create a new text file named SchemaUp in a folder location that is convenient for you to access.
- Copy the following five lines of text and paste them as the contents of the SchemaUp.txt file.
dn:
changetype: modify
add: schemaUpdateNow
schemaUpdateNow: 1 - After you paste the text to the file, ensure that there are no line breaks (carriage returns) between each line of text. If there are line breaks, delete the empty lines. Ensure that you have a hyphen as the last line of text in the file.
- Save the file.
- Open a command prompt as an administrator. To open a command prompt as an administrator, click Start. In Start Search, type Command Prompt. At the top of the Start Menu, right-click Command Prompt, and then click Run as administrator. If the User Account Control dialog box appears, confirm that the action it displays is what you want, and then click Continue.
- At the command prompt, type ldif -i -f SchemaUp.txt, and then press ENTER. If necessary, type the file path to the text file that you saved.
Verify that the schema cache was updated successfully by using Event Viewer
To verify that the schema cache was updated successfully by using Event Viewer:- Open Event Viewer. To open Event Viewer, click Start. In Start Search, type eventvwr.msc, and then press ENTER.
- Expand Applications and Services Logs, and then click Directory Service.
- Look for Event ID 1582, which confirms that the schema cache was reloaded successfully. If you do not see the event, click Find, type 1582, and then click Find Now. Event 1582 confirms that the schema cache was updated.
- Confirm that there are no Critical, Error, or Warning events that are related to the schema that occurred after the schema cache update. To locate events that are related to the schema, click Find, type DS Schema, and then click Find Next.
- Continue to click the Find Next button and review each event until you have verified that there are no Critical, Error, or Warning events that occurred after the schema cache update.
When you confirm that the schema cache was updated, you may no longer need diagnostic logging for schema events. To disable diagnostic logging for schema events, use the Reg command to set the 24 DS Schema value to 0. To set the value of 24 DS Schema to 0, at a command prompt, type the following command, and then press ENTER:
Reg Add HKLM\SYSTEM\CurrentControlSet\Services\NTDS\Diagnostics /v "24 DS Schema" /t REG_DWORD /d 0
The number after /d indicates the value, in this case, the logging level. |