Backup the basis on which disaster recovery is built

We understand the necessity for disaster recovery solutions in today's economy. As business has become more and more dependent on computer data, the need for dependant systems is obvious.

What is acceptable exposure to outage is reducing month by month. Some companies estimate the cost of downtime in $1000s while others stand to lose revenues and the knock on fallout: loss of faith, customer loyalty, etc., in terms of tens of millions per hour during periods of unplanned downtime. The higher the cost of an outage the more likely that, even a short-term outage, can mean the difference between success and failure.

Traditionally disaster recovery planning looks at preventative action to avoid potential problems and how to deal with any unintended system interruptions, however, given today's business vulnerabilities quite simply the requirement is to shorten the time to recovery.

Most disaster recovery planning focuses on network restore, systems replacement, end-user work place replacement (which incidentally only applies to about 20% of disasters - around 40% of all disasters relate to power outage and 30% human error). These aspects of planning are of vital importance, however, it is easy to overlook one key enabler of overall business recovery, the recovery of data.

Without the ability to restore data any disaster recovery planning is pointless. After all, it is the data that gives the business systems a purpose. Companies should set aside a considerable proportion of their disaster recovery budgets to make sure that data is backed up regularly and that backups are built for rapid reinstatement.

In spite of this it is not unusual to find that organisations still do not back up regularly. Some do backups but do not check or test to see how effective these backups are. There was a case where an organisation had been religiously backing up every day, when the disaster occurred they turned to their off-site backup tapes to restore the data to the systems and found the tapes blank. No one had tested the system to see if anything was actually being backed up on the tapes.

Other companies have tested for data integrity but not tested their ability to restore the data backed up. In fact it would not be a surprise to find that most organisations have not changed or upgraded the backup of this fundamental business asset for several years. The process of backing up mission critical data to tape and then taking those tapes off-site (most disasters occur locally) on a scheduled basis has the advantage of dispersing the data asset, however, the time to recovery can be longwinded.

There are alternatives to these traditional methods, one is vaulting which simplifies the process of rotation and retention schedules for off-site copies, by automating the process. In essence the remote tape is treated as a locally installed system by connecting the tape system to the host system. The transfer of backed up data is completed with no negative impact on performance and regardless of the distance involved.

Another option is remote mirroring. This allows the creation of duplicate volumes of data on a physically separate platform. This mirrored data constitutes a real-time data backup. The advantage is that the mirrored data is restored as if it were read directly from a set of disks rather than having to be copied and reloaded to disk from the tape backups. Business can then continue in a matter of minutes rather than hours or even days. The down side is that if the data mirrored is corrupt in any way then the mirrored version is also corrupt. To cover this eventuality traditional backup methods are essential.

So tape vaulting and remote disk mirroring are not a total solution. They are certainly technologies that should be incorporated into the disaster recovery plan. Ultimately, companies will find that a mixture of traditional, vaulting, remote mirroring and replication is applicable to their business depending on the criticality of their particular systems and applications.

Given the explosion of data and the reliance that businesses have on their system enabled applications and the data held on those systems and the associated costs involved with any data outage, disaster recovery planners should consider reviewing their data protection and disaster recovery strategies to adapt a data backup and restore ability that fits their company's needs and shortens the data time to recovery.