Hot Backup, warm backup, cold backup (hot/warm/cold backup)

1. System Backup

Based on the degree of preparation of the backup system, it can be divided into three categories: Cold backup, warm backup and hot backup.

1.1 The cold backup system is not installed or configured to the same or similar running environment as the current system. Application System data is not loaded into the backup system in time. In the event of a disaster, you need to install and configure the required runtime environment, use the data backup media (tape or CD) to restore application data, and manually or automatically record Isolated Data in batches, switches end users to the backup system through communication lines to resume business operations. Advantage: The investment in devices is relatively small, saving communication costs and less demanding communication environments. Disadvantage: the recovery takes a long time, generally from days to weeks, and the data integrity and consistency are poor.

1.2 warm backup: the backup system has been installed and configured to the same or similar system and network operating environment as the current system, and the application system business is installed to regularly back up data. In the event of a disaster, you can directly back up data on a regular basis, manually or automatically record Isolated Data in batches, or switch end users to the backup system through communication lines to resume business operations. Advantage: The investment in devices is relatively small, and the communication environment is not demanding. Disadvantage: it takes a long time to recover data. Generally, it takes more than 10 hours to several days, resulting in poor data integrity and consistency.

1.3 hot backup is online. The current application system transfers data to the backup system in real time through high-speed communication lines to ensure data synchronization between the backup system and the current application system; you can also regularly recover data from the application system on the backup system. In the event of a disaster, the backup system can quickly Replace the production system and resume business operations without completing or simply completing a small amount of Isolated Data. Advantage: the recovery time is short, usually dozens of minutes to several hours. Data integrity and consistency are the best, and data loss is the least likely. Disadvantages: large equipment investment, high communication costs, high requirements for the communication environment, and complex operation and management at ordinary times.

In computer server backup and recovery, the cold Backup Server (cold server) is used only when the master server is lost. The cold backup server is basically enabled only when software is installed and configured, and then closed until it is needed.

The warm Backup Server (warm server) is usually started periodically, updated based on the content of the master server, and then shut down. The warm backup server is often used for copying and mirroring.

The Hot Backup Server (hot server) is in the starting state at all times and is synchronized with the host. When the host fails, you can enable the hot backup server at any time.

As part of the Software Assurance Protocol Program, Microsoft currently provides free software protocols for cold backup servers for disaster recovery, but does not provide free software protocols for warm backup servers and hot backup servers.

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