-
Title
Domain Controller or Exchange Server Export/Restore Issue: Domain Controller 'STOP: c00002e2' or Exchange Error '-546' -
Description
You are trying to recover either a failed physical/virtual Domain Controller or an Exchange server by exporting a recent recovery point to a Hyper-V virtual machine.
Although the export is completed successfully in both cases, the Domain controller gets a stop error during bootup: 'STOP: c00002e2 Directory Services could not start' while the Exchange Server Information Store Service fails to mount the Exchange Databases.
When troubleshooting the Domain Controller, you get the following errors on every recovery point you attempt to restore:
A device attached to the system is not functioning. - Error Status: 0xc0000001You follow the following steps:c:\> NTDSUTILNTDSUTIL : activate instance NTDSNTDSUTIL : filesYou encounter an error stating that the Jet engine could not be initializedYou attempt to soft recover ntds.ditesentutl /r edbYou get the following message:Error: the log file sector size does not match the current volume's sector size (-546)You attempt an integritycheck by runningesentutl /g c:\windows\ntds\ntds.ditThe results indicate that the jet database is corrupt.You attempt a repairesentutl /p c:\windows\ntds\ntds.ditAgain, the repair failsOn the Exchange Server, you try to mitigate the issue by replaying the logs.c:\> eseutil /c
When it fails, you try going a step further by attempting a hard recovery
c:\> eseutil /r
Again, the operation fails.
In both cases the received message error is similar to the one below:
'Operation terminated with error -546 (JET_errLogSectorSizeMismatch, the log file sector size does not match the current volume’s sector size) after 1.3 seconds.'
-
Cause
In both cases, the issue occurs because the physical sector size that is reported by the storage device changed. Although the Jet database engine that supports the Active Directory Database (NTDS.DIT) or the Exchange Information Store was designed with support for 512-byte and 4-KB physical sector sizes during the initial database creation, it expects that the reported physical sector size remains consistent between sessions. When the Jet database re-initializes, it makes sure that the physical sector size that the database was created for and the current reported physical sector size are the same. When the sector sizes are different, it reports an error. -
Resolution
The key for solving the issue is the error received during the soft recovery attempt:Error: the log file sector size does not match the current volume's sector size (-546)This means that the physical sector size of the original Domain Controller or Exchange Server and the one of the exported one do not match. Specifically, it means that the original sector size was 512Bytes and the current one is 4KB. This happens if the Domain Controller system drive or the Exchange Server drive(s) hosting Databases/Logs has been exported to VHDX as opposed to VHD.To solve the issue re-export the Domain Controller system drive or the Exchange Server drive(s) hosting Databases/Logs to VHD. Another option is converting the VHDX drive to VHD on the using the following PowerShell command launched from the Hyper-V server:PS C:\> Convert-VHD –Path 'VHDX snapshot PATH' –DestinationPath 'VHD Destination PATH'Please note that the full syntax of the convert-vhdx command is:Convert-VHD [-Path] [-DestinationPath] [-VHDType {Fixed | Dynamic | Differencing}] [-ParentPath ] [-BlockSizeBytes ] [-DeleteSource] [-AsJob] [-Passthru] [-ComputerName ] [-WhatIf] [-Confirm] []The exported VM should boot up properly now and the Domain Controller/Exchange Server should be fully functional.Please note that the same issue may potentially occur during dissimilar hardware restores.