Add a Decommissioned Node Back to a ScyllaDB Cluster

This procedure describes how to add a node to a ScyllaDB cluster after it was decommissioned. In some cases, one would like to add a decommissioned node back to the cluster, for example, if the node was decommissioned by mistake. The following procedure describes the procedure of doing that, by clearing all data from it, and adding it as a new node in the cluster

Prerequisites

Before adding the new node again to the cluster, we need to verify that the node was removed using the :doc:nodetool status </operating-scylla/nodetool-commands/status> command.

For Example:

The decommissioned node's IP is 192.168.1.203. Notice that this node is not in the cluster.

.. code-block:: shell

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

Procedure

| 1. Stop the decommissioned node using

.. include:: /rst_include/scylla-commands-stop-index.rst

| 2. Delete the data and commitlog folders

.. include:: /rst_include/clean-data-code.rst

Since the node is added back to the cluster as a new node, you must delete the old node's data folder. Otherwise, the old node's state (like bootstrap status), will prevent the new node from starting its init procedure

| 3. Follow the :doc:Adding a New Node Into an Existing ScyllaDB Cluster </operating-scylla/procedures/cluster-management/add-node-to-cluster/> procedure to add the decommissioned node back into the cluster