A hot site is a disaster recovery (DR) location that is set up and ready to go; that is, one can arrive and continue to work immediately. A cold site is just available space with little, if anything, set up in it. A hot site will have equipment set up with your current data available when you walk in. When you arrive at a cold site you need to set up the equipment, make all connections, load the software, etc. Additionally, there are also warm sites, where equipment is available and set up for you, but you must load or restore your latest data to the system.
Before you choose a disaster recovery site, you must consider your recovery time objective (RTO) and recovery point objective (RPO) data. If your RTO is short (fewer than three hours), a hot site is a good option for you because of its immediate availability. You can continue your daily operations with minimal delay because systems and configurations are already set up to your specific requirements. However, to get this privilege, you need to pay a premium, making hot sites the more expensive disaster recovery site option. If you have a long RTO (more than 18 hours), a cold site is the better option because during the lapse, you can configure your equipment, telecommunications and test the system. So although the set up time is longer for cold sites, it may not have any effect on you if you have a long RTO, plus they are the less expensive option.
For more on hot sites and cold sites in DR planning, check out these other resources from SearchDisasterRecovery.com:
This was first published in January 2010