Which DR Strategy is More Efficient: AIR or Sealed Store?
Providing a sound disaster recovery (DR) strategy is important for any company to avoid the risk of downtime and lost $$$. Smart businesses usually have some sort of mirroring, replication or clustering technology in place to keep mission critical applications and tier 1 servers up and running and always available. But what about DR for the customer’s backup infrastructure? Backup and recovery is looked at as a non-revenue generating “insurance” policy for a company, and has no real business value. That is, until you lose everything and rely on that backed up data to bring your company back to life. With that sobering thought in mind, should a DR strategy be considered for backups?
If your entire data-center goes down, you’ve lost all your production servers, backup catalog and images if you did not plan ahead for off-site copies of your data. Many companies do plan, but are still caught up in the old fashioned method. That solution for DR recovery is centered on shipping tapes to off-site location(s), and then waiting for a disaster to occur, but the risk of shipping tapes is just too great. Unfortunately, there are a high number of restore failure rates when tape is involved; some claims say greater than 40%, but that’s an estimate at best, many say it could be higher. The problem is that not only can tapes get damaged, but they also are easily misplaced, lost or even destroyed. In addition, there are inherent time delays with shipping backs back and forth. Together, it is painful, costly and complex. What if your backup and recovery solution had an integrated DR feature built in, and that the only cost would be to have a secondary site with a backup server to fail over to? What if you could stop putting tapes on trucks?
Symantec NetBackup has a differentiating DR feature built in called “AIR”. Auto Image Replication. It is a feature that can be configured within your backup policies that tells NetBackup to not only backup your data as usual, but replicate the associated catalog and images to another NetBackup server (separate NetBackup domain/environment) in a remote/secondary site. There is no need to import catalogs and images from tape. Those days are long gone. Once replication is complete, the secondary site owns that copy of the backed up images, and customers can immediately perform restores in the secondary site when an outage at the primary site occurs. This significantly reduces your OpEx and CapEx from the traditional method, and gives you the benefit of immediate recoverability.
Other vendors use some less efficient methods that squeeze customers for extra storage costs. What do I mean by extra storage? Once their catalog data is replicated over, it becomes part of a limited accessible “sealed store”. That’s because the vendor keeps the replicated catalog in a read-only mode. That means you can only recover your systems from that store, and it no longer accepts writes. What now? After you recover, the next thing is to start backing everything up again. But because of the sealed store, you never get it to run day-to-day database operations for the backup server. It will always be a “pre-disaster” representation of the backup database. You now have to create a separate working database and catalog for you backup server on a separate volume of storage. This becomes your “post-disaster” copy of the backup catalog/database. Now take what I just laid out and apply it to the process of replicating the catalog/DB back to the original site once it’s up and running. You need both the pre-disaster and post-disaster copies just to get the site all synced up and current again. And yes…they will BOTH be sealed stores. Another second post recovery catalog/database will need to be created. This one will end up being the day-to-day copy going forward. Does anyone see the efficiency or lack of it in this process? More complexity, more administrative overhead and headache, and 3x the storage…where’s the OpEx and CapEx benefits?
Many NetBackup customers have stated how pleased they are with the simple implementation and configuration of AIR, the reliability of it, and the cost savings it has provided. AIR works with both form factors of NetBackup (appliances and software), and is one of the most popular differentiating features that helps Symantec beat the competition. Wouldn’t you want the best solution that’s the easiest to setup and friendliest to your CTO’s wallet? If you would like more information about AIR and other benefits NetBackup offers, please visit us at: