The "3-2-1" rule for data backup is a good rule of thumb.
The "3-2-1" rule for data backup is a good rule of thumb. This means always keeping three copies of your data — one primary copy and two backup copies. One of these backup copies should be a cold copy stored offsite utilizing Data at Rest Encryption (DaRE) for security. In case of a disaster that causes data loss, if you've been backing up your data regularly with DaRE, recovery should be a fairly seamless process with little to no system downtime.