What is a datacenter that operates in parallel with the main datacenter, with active devices and communication, called?

A datacenter that operates in parallel with the main datacenter, with active devices and communication, is known as a hot site. This type of site is fully functional and can take over operations with minimal downtime if the primary datacenter goes offline. The hot site is equipped with the necessary hardware and has current data backups, allowing it to provide real-time data access and support for business continuity.

The key characteristic of a hot site is that it is actively running, meaning that the systems are continuously updated and ready to be brought online immediately without the need for any significant reconfiguration or data restoration. This level of preparedness is essential for organizations that require a high availability of their services.