DSE 4.5.8, OpsCenter 5.1.3.
We are running a multi-region cluster, with 6-nodes running in one DC, and 1 node running as a backup in a remote DC. RF is 3 in DC1, 1 in DC2.
After enabling the OpsCenter backup service, the single node in the remote DC is reaching high CPU every time backup is running (running /bin/find of all strange reasons).
The question is why at all would I want to backup the backup DC (DC2)? Is it possible to configure the Backup Service to confine itself to a single datacenter?
A secondary question is - are 3 copies of my data being backed up in DC1?
Thanks!
Because there are 6 nodes in DC1 (RF3) and 1 node in DC2 (RF1), the node in RF1 has 2x the data as each of the nodes in DC1.
It would make sense that this node (since it has 2x the data) has to work 2x as hard.
Yes, the backup service takes the sstables from each of your nodes (all the data in that node including replicas) and backs them up (either in another local directory, or in s3).
No, currently you can configure OpsCenter backups at the keyspace level but not at the data center level. Having all the sstables for a particular node will enable you to quickly bring back a node without having to bootstrap if this node is lost.
Furthermore, because the backup service restore functionality uses sstable loader, you can also restore a cluster to a new cluster with a different topology.
Check out Mani's blog post for details on the performance of the backup service.