I create secondary index on several tables. Then I ran nodetool -pr on every nodes in the cluster successfully. But when I check table status using nodetool cfstats, finding that outputs information about index table (supposed be hidden). Some index table are 100% repaired, some are 0%. My question is:
If you run full repairs, you'll never see the 'Percent repaired' change, this is only to track incremental repairs, so less than 100% doesn't always mean it isn't repaired, it could be that full repairs were used instead of incremental.
As for the index, repair only applies to the underlying table, so a repair of the table would also rebuild index inconsistencies. If you need to repair just an index, then I don't believe rebuild_index affects the Percent repaired, so I'd reference the base table the index is built on.