Restore Cassandra snapshot (from 3-node-cluster) on developer or test cluster (1-node cluster)

Question

We have set up a backup/restore procedure for our Cassandra production environment via snapshots. The snapshot files, schema and token ring information are copied to S3.

The production cluster is a 3-node-cluster with a replication factor of 3.

For development and test, I would like to restore the snapshots from production into separated clusters. To save money and to keep maintenance easy, it would be nice to restore only the snapshot from one production node. Since we are using a replication factor of 3 in a 3-node-cluster, each snapshot should have all rows. Consistency is also not important for our use-case.

Is it possible (and how) to restore only a single snapshot?

Answer 1

All of your data should exist on all 3 nodes so copying the sstables from any 1 node to your test cluster should be sufficient. Making sure theres a recent repair beforehand may be good idea if worried about consistency.

First create the same schema on the test cluster. Then you can simply take a snapshot with nodetool snapshot -t cloneme . Once complete, copy all the sstables from the folder that is created (cloneme) into the equivalent tables folder on your test cluster. Then run nodetool refresh .

It gets much more complicated if you have a different topology (more nodes, different RF) but since your going with "every node has all the data" its pretty trivial.

Worth mentioning that OpsCenter has a feature to automate the copying of a backup to other clusters .