Technology spotlight Dell AppAssure Recovery Assure The key to Microsoft application protection Your Microsoft applications Microsoft Exchange, SQL Server and SharePoint can be the most business-critical elements within your IT infrastructure. Loss of access to any of them for even a short time can begin to cripple your business, so you have to be sure your backups are fully recoverable when you need them most. Unfortunately, there aren t enough hours in a day to test every backup in advance, and that can leave your company wide open to the threat of data loss if one of your backups has corrupted data. That s why Dell AppAssure developed Recovery Assure technology. It tests every backup automatically, even if you re backing up business-critical applications many times a day. Production machines aren t impacted by the testing process, which takes place on a separate AppAssure Core. Once a backup has been automatically tested and validated, you can be sure it is fully recoverable without going through the time and tedium of manual testing. Let s take a look at how Recovery Assure works. How it works, in brief Dell AppAssure Recovery Assure operates in conjunction with AppAssure s continual incremental-forever backups (AppAssure runs incremental-forever backups after the first full backup for much greater speed and efficiency). Recovery Assure tests every backup automatically Each and every backup is thoroughly checked for recoverability in three ways, even if you re backing up at fiveminute intervals: Mountability Attachability SHA-256 checksum Production machines are unaffected by this process. AppAssure is automatically aware of Microsoft Exchange, SQL and SharePoint instances and the file systems in the machines you re backing up. Each night, the Recovery Assure function goes into action to validate every backup completed that day. If the backup is validated, a green mark appears on the management screen next to that specific backup. This is your assurance of total application recoverability in the event of a disaster. In the rare instance when corruption has occurred, the backup is identified as invalid, marked in red on the management screen, and the administrator is notified immediately to take action. Otherwise, no operator involvement is required. Now for the details Backups are automatically checked to give peace of mind that vital business data is recoverable. These checks include Mountability (Exchange backups), Attachability (SQL and SharePoint backups) and a SHA-256 checksum, executed automatically when the AppAssure Smart Agent detects the presence of Microsoft Exchange, SharePoint or SQL. Mountability checks are only for Exchange and Attachability checks are only for SQL.
For Microsoft Exchange, Dell AppAssure performs checksums on the Exchange database (EDB). Every Exchange database page has a field that contains a checksum of that page that is calculated every time the page is modified. AppAssure automatically calculates the checksum of the backed up EDB pages and then compares the values to the ones stored in the EDB pages to ensure the integrity of the backed up page. By performing a checksum verification on the EDB AppAssure enables administrators to adhere easily to Microsoft s best practice of performing checksum verification (volume integrity graphic below) before log truncation. Best practices alert: Performing a checksum verification on the EDB AppAssure enables administrators to easily adhere to Microsoft s best practices of performing checksum verification before log truncation. But that alone is not enough to achieve best practices for SQL and SharePoint environments. For these you also need: A Mountablity check for Exchange Server An Attachability check for SQL and SharePoint Server We have identified no other backup and recovery product on the market that allows log truncation only if the checksum is successful. This is important because without a successful Exchange backup or the presence of transaction logs, Exchange recovery becomes impossible. To ensure that checksums are done quickly, AppAssure only performs a checksum on EDB pages that have changed since the last checksum analysis. Checksum is not enough While checksum ensures the integrity of Exchange data, it alone cannot guarantee that a backup is recoverable. It only ensures that the Exchange server will boot up. That s why AppAssure takes the extra step of carrying out a Mountability check (as diagramed below) for data corruption to see if there s missing data like incomplete volume groups or EDB, log or file paths that aren t located in the location specified by metadata. 2
Any problem found with a Mountability check or checksum will show up on the dashboard (note the red marks in this screen shot) as an early warning that a backup will not be recoverable and that a new one should be taken. Mountability check provides assurance that an Exchange mount will work during recovery A mountability check simulates a real mount of the Exchange database to the AppAssure Core server. It leverages technology from AppAssure and from Microsoft (ESUTIL) to mount the volumes containing the EDB, system and log paths. This mount is done in the same manner that Exchange mounts its databases to provide certainty that the mount will work during a recovery. 3
Different recovery check for SQL and Sharepoint Due to the nature of their databases, Microsoft SQL and SharePoint require an Attachability check rather than the Mountability check employed by Exchange. The databases are attached to an off-production SQL instance installed on the AppAssure Core Server. AppAssure Attachability check flow chart As you prepare AppAssure to test your SQL and SharePoint environments, use the above screen to select the highest version of SQL used in the environment to be installed on the AppAssure Core Server. For instance, if you are using SQL 2003, 2008 and 2008R2, choose SQL 2008R2. AppAssure will attach the most recent SQL recovery point to the SQL server running on the Core Server on a nightly basis. This check automatically determines whether highly transactional and business-critical databases are thoroughly backed up and tested prior to recovery, running as if the database was restored. If a database fails to attach to SQL, AppAssure will fail the job and send you an alert. 4
The Smart Agent advantage Whether it is Microsoft Exchange, SQL or SharePoint, protecting these applications is simple and straight forward. That s due to the intelligence and power of the ultra-lightweight Dell AppAssure Smart Agent deployed to each system. It automatically detects Exchange, SQL or SharePoint and begins to back up these applications and all volumes associated with them. Simply designate: An AppAssure Repository (where the backups are to be stored) Encryption settings Frequency of backups (default is 60 minutes, but you can set any time period down to every five minutes, which yields 288 recovery points a day) Once you ve made those choices, AppAssure runs on a set-and-forget basis. Smart Agent deployment example Below is an example of how to deploy an AppAssure Smart Agent that will allow AppAssure to provide application-aware protection and automated Recovery Assure testing of a Microsoft application server. 1. Connect to the Dell AppAssure Core Server and deploy the Smart Agent 2. During deployment, the Smart Agent will automatically protect the machine, giving the administrator the option to choose repository and encryption settings. 3. Once the machine is protected, snapshots will start immediately. Later, usually in the evening, the Core Server will perform the appropriate checks. For more information For more information on AppAssure Recovery Assure, or to see it in action for yourself, please contact a sales rep and schedule a one-on-one demonstration of Dell AppAssure backup and recovery software. Or, if you re ready to try it yourself, why not download a full working copy for your own 14-day trial evaluation? 5