The tools for monitoring Cassandra cluster include nodetool, Jconsole and Opscenter. All these tools for monitoring cluster works by communicating through JMX(Java Management Extension). In Cassandra Through JMX, explores many metrics and commands which any of them. These tools can use to monitor and manage a Cassandra cluster. In this article we will discuss nodetool. Nodetool: It is one of the important tool for monitoring and managing Cassandra cluster. There are many options are available through nodetool for monitoring a cluster. For complete list of nodetool options used the following CQL query.
nodetool help;
Let’s have a look some of few very important nodetool commands for monitoring Cassandra cluster. For example:
1. nodetool status 2. nodetool info 3. nodetool ring 4. nodetool cfstats 5. nodetool cfhistograms
These are explained as following below. 1. nodetool status: It is defined as the status of a node. It describe the state, IP address of a node, load carrying, owns, host id and rack information. To check the nodetool status used the following CQL query.
nodetool status;
Let’s have a look on screenshot given below.
nodetool info;
Let’s have a look on screenshot given below.
nodetool options ring ( -r | --resolve-ip ) --
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$ nodetool [ options ] tablestats [ -H | --human-readable ] [ -i table [, table ] . . . ] [ - - ] [ keyspace | table | keyspace.table ] [keyspace | table | keyspace.table ]
Let’s have a look on screenshot given below.
nodetool options tablehistograms [--] keyspace_name table_name or nodetool options cfhistograms
Let’s have a look on screenshot given below.