Adaptive data protection for a multi-node data cluster

A system comprising:

• a storage manager that executes on a first computing device comprising one or more first hardware processors;
• a media agent that executes on a second computing device comprising one or more second hardware processors;
• wherein one or more of the storage manager and the media agent are communicatively coupled to a cluster that comprises a plurality of nodes,
• wherein each node among the plurality of nodes comprises one or more hardware processors and data storage, and
• wherein each node hosts an instance of a database management system (DBMS) and a data agent associated with the DBMS, and
• wherein each node stores a database maintained by the instance of the DBMS;
• wherein the storage manager is configured to:
• receive a trigger for a backup job of data stored among the plurality of nodes of the cluster,
• identify a first data agent that was previously in communication with the storage manager in a preceding backup job, wherein the preceding backup job backed up data stored among the plurality of nodes of the cluster, wherein the first data agent is hosted by a first node among the plurality of nodes of the cluster, and
• request, from the first data agent, information about a current configuration of the cluster;
• wherein the first data agent is configured to, responsive to the storage manager, report to the storage manager:
• that a second node is currently operating as a principal node among the plurality of nodes of the cluster, and that other nodes are currently operating as replica nodes among the plurality of nodes of the cluster, and wherein the principal node is responsible for replicating data of the database at the principal node to the replica nodes;
• wherein the storage manager is further configured to:
• based on a preference associated with the cluster, initiate the backup job, which is configured to back up transaction logs of the principal node of the cluster,
• wherein the principal node, which is distinct from the first node, hosts a second data agent, and
• instruct the second data agent and the media agent to perform the backup job,
• wherein one or more backup copies of the transaction logs at the principal node are generated in the backup job and are stored by the media agent at a secondary storage that is distinct from the principal node.