3-2-1 Backup: Copies, Locations, and Offsite Storage Explained Simply
The 3-2-1 backup rule tells you exactly how many copies of your data to keep, what types of storage to use, and where to store them. This guide breaks down each component in plain terms so any IT professional can implement it immediately. The 3: Three Copies of Your Data Three copies means your production data plus two backup copies. Why three? Because hardware fails. If your only backup copy sits on the same storage system as production and that system fails catastrophically, you have nothing. Two copies means losing one still leaves you recoverable. Three copies ensures that even if two fail simultaneously, you remain protected. The three copies do not need to be identical in format or retention. Your local backup copy might hold 30 days of restore points. Your offsite copy might hold 90 days with longer-interval snapshots. Both serve different recovery scenarios. The 2: Two Different Media Types Two different media types means your copies are not all on the same class of storage. If...