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Backup or Replication for Domain Controller

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Beginner
Posts: 2
Comments: 1

When i backup a Domain Controller and restore it, all is fine with AD, Exchange and SQL Databases.
When i replicate a Domain Controller from ESX1 to ESX2 the AD, Exchange and SQL Databases are not okay.

I need both! Replication from ESX1 to ESX2 and a Backup to our NAS. In the other Hand it would be okay when i make a Backup directly to ESX2, but there i have no SMB/CIFS/FTP. Recovering 1TB Domain Controller from NAS is PAIN.

Why does Replication not savely transfer AD, Exchange and SQL Database. And wh

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Acronis Program Manager
Posts: 22
Comments: 3742

Hi Falko,

Can you please clarify what exactly doesn't work when you replicate your DC? In terms of data consistency it should be the same state for both replica VM and the backup, since both replication and backup processes are using quiesced snapshot to capture the state of original VM. Getting the symptoms would let me guide you more accurately.

Thank you.

--

Best regards,

Vasily

Acronis Virtualization Program Manager

Beginner
Posts: 2
Comments: 1

After replication of DC1 and DC2 and booting the replicated machines in a test network, the Active Directory is corrupted, Active Directory Sync between DC1 and DC2 not working and Group Policies dont work with a test client. With Windows Backup you need to make a System State backup to recover Active Directory correctly. 

With normal backup and recovery this is working but not with replication. Do you make a System State backup with Backup Task but not in Replication?
Over a backup task im also able to say that there is an exchange, sql server, with replication i don't have this options to select.

Acronis Program Manager
Posts: 22
Comments: 3742

Hi Falko,

The difference between backup and replication is that replication is reading the data in sector-by-sector mode while backup process is file-system aware, so it reads through NTFS. However in terms of the system state which is being read (and then put into backup/replica VM) - it is the same quiesced snapshot state for both backup and replication.

The application-aware processing option in backup captures the metadata of the applications to enable granular recovery for SQL/Exchange. For AD the app-aware processing is checking for consistency of the responsible VSS writers to capture an analogue of system state backup (so that there will be no problems upon recovery). For replication of Domain Controller VSS is used as part of quiesced snapshot processing automatically by VMware tools, but there are no additional pre-checks.

I'd recommended contacting our support team for assistance, so that we can reproduce the problem (I can only guess that it's related to some NT sigantures of the disks which AD may be dependent on and which are different in case backup/restore, but remain the same in case of replication) and find appropriate solution.

As a workaround you can utilize Run VM from Backup functionality in your DR site - in this case you won't need large datastores to keep entire replica VMs, but you will be able to mount these VMs directly from backup and keep only the generated changes on relatively small datastores.

Thank you.

--

Best regards,

Vasily

Acronis Virtualization Program Manager