Cassandra makes it easy to manage its cluster, one or more nodes joined together on a distributed decentralized fashion. Nodetool is a built-in command line interface to view stats, administer, data backup and recovery, tracing etc.
Nodetool is located at <cassandra-installation-dir>/bin/nodetool, like /opt/cassandra/nodetool.
If we are said to manage a running cluster of Cassandra, use these following commands to gain an overview of the cluster.
command 1: info
$ nodetool info
Provides node information including the token and on disk storage (load) information, times started (generation), uptime in seconds, and heap memory usage.
command 2: status
$ nodetool status
$ nodetool status <keyspace>
Provide information about the cluster, such as the state, load, and IDs. Status command with a Keyspace provides, data owned by that node for the specified keyspace.
command 3: ring
$ nodetool ring
$ nodetool ring <keyspace>
Ring command is similar to status command; it provides the data ownership on each token with in a ring.
command 4: describecluster
$ nodetool describecluster
Provide the name, snitch, partitioner and schema version of a cluster. Schema version should be the same for all nodes within a cluster
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