In preparation for the Active Directory forest to be upgraded (to Windows Server 2012 R2), it may be prudent to re-evaluate Active Directory disaster recovery plans.
Active Directory if configured correctly will just sit there and work; servicing all requests that are presented and because of this robustness, its importance is often overlooked and its criticality not understood.
Management buy in.
The most critical component in the disaster recovery plan, is the education of management and key stakeholders in the criticality of Active Directory to the business. No Active Directory can mean, no authentication; no authorisation; no name resolution or no printing; effectively the IT function may cease to operate until the Active Directory is restored or made available.
Plan and approach.
Define what Active Directory recovery scenarios that are being catered for, is it total loss of the Active Directory or the loss of objects within the Active Directory?
Agree with the business and calculate realistic Recovery Point Objectives (RPO’s) and Recovery Time Objective (RTO’s) for Active Directory.
RPO – this is the point where you have to recover to (or the amount of information you can afford to lose).
RTO – this is the time you have to recover the environment back to the RPO.
Choose your method of backup
When if actually comes to backing up Active Directory, technical insight is needed to understand the scenarios that are being protect against. Ensure that each scenario is catered for so that Active Directory can be recovered.
In a worst case scenario it would mean restoring a single domain controller from backup and then rebuilding all the existing domain controllers to be domain controllers to this restored domain.
This could be a logistical nightmare to perform and orchestrate.
This would usually mean restoring a domain controller from backup and then marking the object(s) that are to be recovered as authoritative.
Active Directory Recycle Bin.
The Active Directory Recycle Bin provides a certain degree of insurance in protecting Active Directory, but it will only enable the recovery of deleted items and not for example the recovery of modified users or groups. All domain controllers must be running at a minimum Windows Server 2008 R2 and the forest mode is Windows Server 2008 R2.
All of the well-known backup providers support the backing up of Active Directory, a key component of backing up the AD is that it is not only the Operating System that needs to be backed up, but the entire system state, which includes all the underlying components of the Operating System and Active Directory.
Quest Recovery Manager for Active Directory – Forest Edition.
The only tool I have found on the market that provides Active Directory Disaster Recovery from a single pane of glass, it enables recovery from a single attribute to a full forest recovery.
Test your processes
Whatever process or method you take to back up your Active Directory, ensure that you are confident and able to recovery your Active Directory not only in the time required, but also physically able to do so.
As I review and update my old consulting notes I have decided to publishing them. These are by no means definitive and are intended as an ‘aide memoire’ to enable discussion.
Please feel free to comment.