Fix Broken Index Shard Snapshot File Preventing Snapshot Creation #41476

original-brownbear · 2019-04-24T09:15:49Z

The problem here is that if we run into a corrupted index-N file, instead of generating a new index-(N+1) file, we instead set the newest index generation to -1 and thus tried to create index-0
- If index-0 is corrupt, this prevents us from ever creating a new snapshot using the broken shard, because we are unable to create index-0 since it already exists
- Fixed by still using the index generation for naming the next index file, even if it was a broken index file
Added test that makes sure restoring as well as snapshotting on top of the broken shard index file work as expected
closes Repository with Broken Shards' index-N File Can't Create New Snapshots #41304

backport of #41310

…astic#41310) * The problem here is that if we run into a corrupted index-N file, instead of generating a new index-(N+1) file, we instead set the newest index generation to -1 and thus tried to create `index-0` * If `index-0` is corrupt, this prevents us from ever creating a new snapshot using the broken shard, because we are unable to create `index-0` since it already exists * Fixed by still using the index generation for naming the next index file, even if it was a broken index file * Added test that makes sure restoring as well as snapshotting on top of the broken shard index file work as expected * closes elastic#41304

elasticmachine · 2019-04-24T09:15:50Z

Pinging @elastic/es-distributed

original-brownbear · 2019-04-24T09:44:42Z