Foreword
Cassandra is a decentralized distributed database. A data is distributed across multiple peer nodes that have multiple copies. We need multiple copies of regular check to see if there are inconsistencies. For example, because the disk is damaged, it may result in the loss of a copy, so that multiple copies of the same data will be inconsistent.
nodetool repair
nodetool Cassandra provide this provides a repair tool that can be used daily inspection data consistency. When the repair or modify the keysapce copy of the configuration, but also need to run this tool.
You can nodetool help 'repair'see the command help, as follows:
NAME
nodetool repair - Repair one or more tables
SYNOPSIS
nodetool [(-h <host> | --host <host>