When trying to restore a 2.2 snapshot on 5.1.1 cluster the below exception returned. out of 10 shards, 2 shards failed recovery. Able to restore the same snapshot in 2.2 and 5.5 cluster.
Any idea why? there is no memory problem or permission issues. Similar Snapshot restored fine on 5.1.1 cluster some days back.
IndexShardRestoreFailedException[Failed to recover index]; nested: FileAlreadyExistsException[C:\elasticsearch\elasticsearch-5.1.1\data\nodes\0\indices\Zttv7nGBRn-KHM0uakuQ3A\2\index_km_Lucene50_0.doc];
Appreciate your help