Summary
On occasion where a node has been decommissioned or removed, sometimes the process may not complete. This article discusses how to remove the node from gossip using JMX tools
Symptoms
The node may have long since been removed from the cluster using nodetool decommission on the node itself of nodetool removenode <Host ID> on another node, but is still showing up in nodetool status for example:
Datacenter: DC1 =============== Status=Up/Down State=Normal/Leaving/Joining/Moving -- Address Load Tokens Owns Host ID Rack UL 10.0.0.1 275.12 GB 1 16.7% 22005584-544e-47bb-80a7-c5e283be137b RAC1 UN 10.0.0.2 335.22 GB 1 16.7% 6e3e4793-9161-4873-98f1-bc040ae907e7 RAC2
The output of the nodetool netstats command may also show that all streams are complete at 100%
Cause
Depending on what version DSE is in use this may be caused by a known issue with gossip. One of the most recent ones at the time of writing this article was CASSANDRA-10371
Solution
Using a graphical JMX tool or a command line too you can remove the node from gossip using the mbean org.apache.cassandra.net Gossiper.unsafeAssassinateEndpoint(<IP address>)
Here's an example using jconsole:
