DR Managed Hot Standby
For the DR Managed Hot Standby service, the secondary region always has a complete Sitecore environment setup with all Azure resources matching the sizes/instances in the primary data center. This recovery option has the shortest RTO because the failover is automatic.
The setup steps are:
Provision the Control Resource Group and the relevant underlying resources and services that monitor DR states.
Deploy a new Sitecore environment in the secondary data center.
Set up replication for the SQL server.
Backup, synchronize, and provision state management automation (covers the backup of webapps and synchronizes SQL server databases in the failover group and keeps the secondary Sitecore environment updated.
Set up the Traffic Manager to redirect traffic and switch between primary CD and secondary CD.
Set up various alerts to notify the Managed Cloud Operations team.
Initiating a failover
Managed Cloud continuously checks the health of the primary data center. If three out of the five data centers report an issue, then an alert is raised to the Sitecore Managed Cloud Operations team and the automated failover is triggered.
In the event of a disaster, Sitecore notifies the customer of the automated failover event. Sitecore triggers the recovery procedure through the Traffic Manager that automatically redirects traffic via a DNS change to the secondary Sitecore instance.
The return to the primary data center is performed automatically by doing failover steps again and directing the traffic to the original Sitecore instance after it is detected as online.