Change initial token to vnode in Cassandra 2.1.7

Question

Currently I am running Cassandra cluster with 4 nodes with initial token range. It has not been repaired since long time due to gc failed.

Now, I want to change initial token to vnode (num token). What should I do? 1. Shall I run 'nodetool repair' and then change initial toke to vnode? 2. Shall I change initial token to vnode first and then run 'nodetool repair' ? 3. Do I need to run 'nodetool repair' on all the node or on any one node?

Answer 1

You cannot directly convert a single-token nodes to a vnode. However, you can configure another datacenter configured with vnodes already enabled and let Cassandra automatic mechanisms distribute the existing data into the new nodes. This method has the least impact on performance.

Existing cluster to vNodes

Nodetool repair will have to be ran on each node and doing with advanced option -pr will be helpful

nodetool repair -pr