I have an existing Cassandra Cluster. I removed a node from the cluster. Then I decommissioned the removed node, stopped it, updated its config so that it only has itself as the seed and in the cassandra-topology.properties file, even deleted the data, commitlog, and saved_caches. But as soon as I start it backup it is able to join back to the cluster. How does this node know the information of the existing cluster and was able to join it ?