Remove a Node from a Scylla Cluster (Down Scale)

Use these instructions when you want to remove nodes in-order to reduce the size of your cluster

Procedure

  1. Run the nodetool status command to check the status of the nodes in your cluster
Datacenter: DC1
Status=Up/Down
State=Normal/Leaving/Joining/Moving
--  Address        Load       Tokens  Owns (effective)                         Host ID         Rack
UN  192.168.1.201  112.82 KB  256     32.7%             8d5ed9f4-7764-4dbd-bad8-43fddce94b7c   B1
UN  192.168.1.202  91.11 KB   256     32.9%             125ed9f4-7777-1dbn-mac8-43fddce9123e   B1
DN  192.168.1.203  124.42 KB  256     32.6%             675ed9f4-6564-6dbd-can8-43fddce952gy   B1
  1. If the node status is Up Normal (UN), use the nodetool decommission command

Use the nodetool netstats command to monitor the progress of the token reallocation

  1. If the node status is Down Normal (DN), use the nodetool removenode command

When using nodetool removenode we need to use the Host ID of the node

For Example:

nodetool removenode 675ed9f4-6564-6dbd-can8-43fddce952gy

Use the nodetool netstats command to monitor the progress of the token reallocation

  1. Verify that the node removed by using the nodetool status command
Datacenter: DC1
Status=Up/Down
State=Normal/Leaving/Joining/Moving
--  Address        Load       Tokens  Owns (effective)                         Host ID         Rack
UN  192.168.1.201  112.82 KB  256     32.7%             8d5ed9f4-7764-4dbd-bad8-43fddce94b7c   B1
UN  192.168.1.202  91.11 KB   256     32.9%             125ed9f4-7777-1dbn-mac8-43fddce9123e   B1

Procedures