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- The commit leader becomes the owner of the segment being committed. It will make this segment downloadable using a new HTTP end point. After the leader commits the segment metadata, it uploads the segment to the configured deep storage as a backup. The deep storage uri will be added to the segment location list in controllerZookeeper.
- Similarly other replicas will keep updating this 'segment location' via the Controller.
- When the controller asks a server to download the segment for whatever reason, the server will check the segment location list. It will first try to download it from a deep storage uri to minimize the impact on servers. If there is no such uri, it will go down the list of servers to download the segment.
- All existing error handling routines remain unchanged. The next section lists diagrams showing the critical scenarios of (1) happy path, (2) controller failure and (3) slow server downloading from deep storage or Peer server.
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