Cluster Data BackupsMenu
This section describes the automated Snapshot Backup service that is provided to all Instaclustr-managed clusters. It also describes the optional Continuous Backup service that allows for more frequent backups to be taken.
Instaclustr provides two backup services: Snapshot Backup and Continuous Backup. Both backup services transfer backed up data to cloud storage (e.g. S3 storage bucket for an AWS cluster) for retention for a period of 7 days.
In addition, it also describes the Instaclustr’s backup functionality on Cassandra Secondary Indexes.
Snapshot Backup is the default backup service. Under Snapshot Backup, all cluster nodes will perform a snapshot backup once every 24 hours. This involves running a nodetool snapshot operation across all keyspaces on the node and then uploading the snapshot files to cloud storage. Node snapshot timing is staggered to reduce the impact of backup operations on the overall cluster performance.
Instaclustr platform provides a feature to back your cluster manually from the console. Starting a backup will trigger a backup across all nodes in the cluster. All nodes will simultaneously flush their memtables to disk and may have a brief performance impact.
Backups of Cassandra Secondary Index
The Instaclustr backup services back up any secondary indexes a cluster has to a cloud storage location (e.g. S3 storage bucket for an AWS cluster). The exact location and the file naming convention used for the backed up files depends on the type of secondary index and the version of Cassandra.
- Regular Secondary Index
- Cassandra 2.2 + Secondary index will be stored as sstables under a separate directory inside their respective tables. The secondary index directory is named as ‘.nameOfTheIndex’. The naming convention of sstable files is,Cassandra 2.2.x + – ‘md-#-big-*’, eg: md-1-big-Data.db
- Cassandra 2.1.x & Cassandra 2.0.xSecondary index will be stored as sstables in the same directory of their respective tables. The naming conventions of sstable files are,Cassandra 2.0.x – ‘keyspace-table.nameOfTheIndex-jb-#-*’, eg: testkeyspace-testtable.testindex-jb-1-Data.dbCassandra 2.1.x – ‘keyspace-table.nameOfTheIndex-ka-#-*’, eg: testkeyspace-testtable.testindex-ka-1-Data.db
- SASI Index (SSTable Attached Secondary Index)
Another important difference with SASI Index is that if a cluster already has SASI index before the Instaclustr backup service is started, the backup service will not backup SASI index. In such a scenario, the Cassandra service needs to be restarted. If this situation occurs on a production cluster, you can contact our technical support team for assistance.
naming convention : md-1-big-SI_table_column_idx.db