Does Real-Time Backup and Recovery Exist Today? Part 2 Page 2
Hot Database Backups and Data Replication Services Heat Up
Companies are also looking toward ‘hot’ database backups (which work while the database is still running), because they can’t afford to shut down their databases. Sante reports that many ONStor customers regularly SNAPshot file systems that contain active databases as well as other data types.
He says the SNAPshots can then be backed up to disk as a background activity, effectively backing up a live database. “The speed of SNAPshots combined with the non-intrusive nature of block-level data replication delivers a form of ‘hot’ database backup,” says Sante.
Toor asserts that open file backup is already a reality. “I think that most major DB players have open file backup agents and know that ‘hot’ backup is a must,” he says. “SNAPshot is a technique that does this already and we are working on volume SNAPshot.”
More and more companies are also showing a greater interest in data replication services. For companies that require offsite disk-based backup, outsourcing a portion of that process may make a lot of sense, according to Sante. “Just as companies find efficiencies in third-party site hosting, the data replication process may benefit from the economies of third-party site maintenance.”
Sante also states that a complication could be the need for seamless interaction between the onsite and offsite locations. “This interaction would be easiest when two sites share common infrastructure, possibly leading to a co-location model rather than a service provider model.”
A Coexistence in Store for Tape and Disk Backup?
Although disk backup will continue to make inroads into tape’s territory, many industry experts believe that organizations will use it as an adjunct rather than a replacement. And as vendors introduce cheaper disk arrays, many companies will use ‘staging to disk’ where disk storage is used for a few months and then the data is moved to tape for long-term storage.
So, it may be that disk and tape will always be complimentary. Much of the appeal of disk-based backup, according to some industry experts, lies largely in its simplicity. Data can be instantly restored from a secondary disk, rather than invoking a complicated restore-from-tape procedure. “An elaborate staging architecture in which data is transitioned among various levels of storage defeats an element of that simplicity, and may in fact be unnecessary,” says Sante.
Many experts agree that tape will continue to be used because it enables data that is not replicated to disk to be stored offsite. In the end, the bottom line is ensuring that the security of data is completely protected, so expect IT managers to stick with tape until the alternatives are exceptionally well proven.