What is Cold Standby Mode?
In the Cold Standby mode, there are only two data centers. The primary data center is up and running, whereas the standby data center is turned on only when the primary data center goes down. The standby data center has a very basic setup. On failure of the primary data center, the standby data center replaces the primary data center. As part of disaster recovery procedure:
Bring up the services.
Run the scripts for backup and restore.
Reconfigure the load balancer to redirect the traffic to the standby data center.
Cold standby mode is cost-effective in terms of data center operations. However, there is a downtime if the primary data center goes down. The RPO and RTO for cold standby mode is high as compared to rest of modes.
Note:
Generally, the standby data center in the cold standby mode is a standalone system. In case of disaster, the standby data center, in the cold standby mode, replaces the primary data center. After the problem is resolved, you must bring the primary data center back into action.