Despite the increased use of disk and wide-area network (WAN) replication, tape continues to play a vital role in data protection strategies. The location of your backup tapes is a key factor in any disaster recovery (DR) plan, and should be chosen based on your organisation's defined recovery time objective (RPO) and recovery point objective (RPO).
Governing bodies such as the Financial Services Authority and guidelines such as the BS25999 international business continuity standard provide recommendations for offsite backup tape, but they aren't prescriptive regarding distance and don't tell you whether your own remote office (or a third-party location) should be used. Their best practices include risk assessment associated with security of data in transit and offsite, as well as with regard to its location. The latter includes ensuring that your offsite location doesn't fall within potential quarantine zones, access routes or environmental disaster belts that would be affected in the same way as the production site those tapes are protecting.
Here are some best practices for storing backup tapes offsite:
- Store materials within a reasonable distance for timely recovery. A radius of up to four hours is commonplace, but is subject to your business-defined recovery objectives and the threats you're protecting against.
- Keep all tapes, disks and other materials in a controlled environment safe from heat, humidity, dust, etc.
- Duplicate all onsite backup media (no single copies) and send them offsite daily
- Keep an inventory of all offsite materials
- Periodically test long-term retention media and migrate it to new media as technology evolves to ensure data recoverability