A system receives, by a centralized storage of the distributed backup system, a plurality of data archives including a plurality of data indexes from a plurality of backup agents, wherein each respective backup agent generates a respective data archive and a respective data index. The system merges, by the centralized storage, the plurality of data indexes into a cumulative index for access by a user, wherein the merging includes: extracting each respective data index from the plurality of data archives, and adding each respective data index to the cumulative index without mounting the plurality of data archives or accessing data chunks within the plurality of data archives.