Migration from tiered to diskless design draft

[AnatolyPopov]

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[giuseppelillo]

One aspect missing is the possibility of split brain / zombie leaders during the migration.
A zombie leader might choose a different boundary than the one chosen by the real leader. This can be solved through leader epochs though (when committing the boundary to the Control Plane, the request with the higher leader epoch wins).

[giuseppelillo]

What's the difference between this design and the one already accepted upstream?

[AnatolyPopov]

I re-read the KIP carefully and so far my understanding is that it describes only follower fetch during bootstrap. And here I'm trying to describe client fetching of tiered offsets from follower.