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You should only consider switching backup products if your current backup product can't meet your requirements (see Pros and cons of alternative backup methods). There are a number of requirements that might prompt you to consider alternatives, such as:
- Remote office data protection
- Backing up large databases
- An application with an RPO of zero
The most common area where backup requirements are difficult to meet is the remote office. Traditional backup schemes can't meet remote office RTO/RPO requirements. There's either too much data or not enough bandwidth to support a reasonable RTO or backup window. Any CDP product can provide backup and recovery of a remote office; most offer two methods. If long RTOs are acceptable, remote sites can back up directly to your central office. In the case of a disaster, just copy the data from the central data center to a disk or tape and send it to the remote site. If this meets RTO requirements, it's the least-expensive option. For tighter RTO requirements, install a backup device at the remote office. The remote office systems can back up to it, and it can then replicate the data to the central site. This provides local recovery and disaster recovery without touching a tape.
CDP products are also superior to traditional backup methods when backing up very large databases. There isn't enough time or horsepower available to transfer several terabytes of data to tape every day. A CDP product could continually back up a database throughout the day, with no noticeable backup window or application impact. Depending on the product, a stringent RTO and short RPO could also be met. Also, some products provide a disk-based copy that can be used in a disaster situation while the real volume is being recovered.
Finally, some database applications require a zero RPO. Most databases can meet such a requirement if they're configured correctly, and if the transaction log is backed up throughout the day. If your database supports that kind of functionality, it's probably best to stick with it. If not, try one of these newer methods.
This was first published in June 2005