Welcome to the next part of the cstar post series. The previous post introduced cstar and showed how it can run simple shell commands using various execution strategies. In this post, we will teach you how to build more complex custom commands.
Spotify is a long time user of Apache Cassandra at very large scale. It is also a creative company which tries to open source most of the tools they build for internal needs. They released Cassandra Reaper a few years ago to give the community a reliable way of repairing clusters, which we now love and actively maintain. Their latest open sourced tool for Cassandra is cstar, a parallel-ssh equivalent (distributed shell) that is Cassandra topology aware. At TLP, we love it already and are sure you soon will too.
nodetool assassinate command is meant specifically to remove cosmetic issues after
nodetool decommission or
nodetool removenode commands have been properly run and at least 72 hours have passed. It is not a command that should be run under most circumstances nor included in your regular toolbox. Rather the lengthier
nodetool decommission process is preferred when removing nodes to ensure no data is lost. Note that you can also use the
nodetool removenode command if cluster consistency is not the primary concern.
In our previous post, “Should you use incremental repair?”, we recommended to use subrange full repairs instead of incremental repair as CASSANDRA-9143 could generate some severe instabilities on a running cluster. As the 4.0 release approaches, let’s see how incremental repair was modified for the next major version of Apache Cassandra in order to become reliable in production.