In this screencast we will cover both how to add a secondary fifo zone to the Riak cluster as well as how to migrate your existing sniffle database backend from the legacy HanoiDB to the new LevelDB backend. Going forward, LevelDB is now the recommended format for all Project-FiFo implementations.
It is important to note that this screencast demonstrates a 2 node Riak cluster which does not offer any real fault tolerance. In production it is recommended that you plan your cluster according to your own requirements and distribute your fifo zones across separate hardware nodes to ensure redundancy and no single point of failure.
To make sure that your cluster is always available to respond to read and write requests, Riak recommends a “sane default” of N=3 replicas. This requirement can be met with a three or four node cluster.
Covered in this Screencast:
- Adding secondary fifo zone 2.
- Installing sniffle packages in new zone 2.
- Ensuring config is set to use LevelDB backend
- Joining sniffle to Riak cluster to fifo zone 1
- Removing zone 1 (HanoiDB) from cluster.
- Changing zone 1 to use LevelDB
- Joining zone 1 back into cluster
Optional Last Step : Should you want to return to a single fifo zone setup using LevelDB, an optional last step would be to issue a “leave” request on your fifo zone 2. Once the leave has completed you will be left with a single install and could then delete your second fifo zone machine that would no longer be part of the cluster.