Riak KV functions as a multi-node system, so cluster-level version upgrades and restarts can be performed on a node-by-node or rolling basis.
The following steps should be undertaken on each Riak KV node that you wish to replace:
1. Create a free node:
a. Create an additional node with similar specifications to the other nodes in the cluster.
b. Or leave a node that is currently in the cluster:
riak-admin cluster leave »nodename«
After creating a node or leaving a node, wait for all transfers to complete:
2. Join the free node to your cluster:
riak-admin cluster join »free_node«
3. Next, replace the free node with an existing node:
riak-admin cluster replace »free_node« »nodename«
4. Then review the cluster transition plan:
riak-admin cluster plan
5. And commit the changes:
riak-admin cluster commit
6. Wait for all transfers to complete:
7. Repeat steps 2-6 above until each node has been replaced.
8. Join the replaced node back into the cluster or decommission the additional node that was created.