The Trouble with Tape
Tape backup can provide for the long-term archival needs of the virtual servers; however tape cannot provide the level of recoverability
required for critical business applications. Rebuilding one application from tape can be a difficult and lengthy process. Recovering four or more
applications at the same time from tape to rebuild one physical server will result in an excessive period of downtime, likely more than the
business can afford.
Organizations may not understand how vulnerable their data and business remain to disaster - even after they've made a huge up-front and
ongoing investment in tape-based disaster recovery. An article in SearchSecurity reports that in a survey of 500 IT departments, as many as
20% of routine nightly backups fail to capture all data. Among participants of another survey cited in this article, 40% of IT managers were
unable to recover data from a tape when they needed it.1 This is a significant concern for corporations that are regulated as they can face
the risk of being out of compliance if they cannot produce required data when they need it
Tape backup also places limits on your recovery point objective (RPO), the point in time to which you can recover your systems should disaster
strike. Periodic tape backup guarantees hours of lost data in the event of a disaster. Suppose, for example, that a critical system fails anytime
today; the best you can do is recover to yesterday's data, which will be at least twelve hours old. The later in the day disaster strikes, the older
the data from which you'll recover. In addition, recovering from a disaster, any data not backed up is lost for good - unless you recreate it
The cost of permanently lost data is high and includes the cost of the revenue that the data represents, the business value you can extract
from it, and the cost to recreate it. Consider:
● How much money would your agency lose if you lost all your transaction data for the last twelve hours, or even the last ten minutes?
● What is the value of the knowledge contained in your agency's last twelve hours worth of e-mails and e-mail attachments? What would it
cost to have your engineers recreate the last twelve hours worth of original or edited CAD/CAM drawings?
In The Cost of Lost Data, a Pepperdine University report updated in 2003 - before the advent of Sarbanes-Oxley - Dr. David Smith estimates
the average cost of irrecoverably lost data at more than $10,000 per megabyte lost.2 But if the data lost is business transaction data or data
that's especially expensive to reproduce and key to your company's disaster recovery plan, your costs could be much, much higher.
The Cost of Downtime
When a large-scale disaster strikes, with tape backup you're out of business until you can restore your systems and your data from your tapes.
This kind of restoration takes a minimum of several hours, and can easily take days or even weeks.
Gartner Group estimates that the average cost of network downtime for larger corporations is $42,000 per hour; Contingency Planning
Research pegs the average hourly downtime costs for many businesses at roughly $18,000. The key to a successful disaster recovery plan is to
focus not just on the data (RPO) but also on the applications that end users run to gain access to that data. Recovery Time Objective (RTO) is
generally defined as the amount of time it takes to regain access to business-critical data. Solutions like tape backup, which have an RTO of
hours or days, don't provide the level of recoverability that most companies require.
Full system rebuilds and tape restores are unacceptable recovery methods for meeting the RPO/RTO of mission critical applications and leave
organizations vulnerable to lengthy recovery times and potential data loss. Architecting for maximum availability throughout various types of
outages presents a challenge that can be solved through a combination of real-time replication, application availability and virtualization
technology. Leveraging virtualization along with high availability storage solutions and data protection software like Double-Take can help
businesses economize
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