Enabling incremental snapshot backups

Steps to enable incremental snapshot backups. When incremental backups are enabled, DataStax Enterprise hard-links each memtable flushed to an SSTable to a backups directory under the keyspace data directory.

When incremental snapshot backups are enabled (disabled by default), DataStax Enterprise hard-links each memtable-flushed SSTable to a backups directory under the keyspace data directory. This allows storing backups offsite without transferring entire snapshots. Also, incremental backups combined with snapshots provide a dependable, up-to-date backup mechanism. Compacted SSTables do not create hard links in /backups because these SSTables do not contain any data that has not already been linked. A snapshot at a point in time, plus all incremental backups and commit logs since that time form a compete backup.

As with snapshots, DataStax Enterprise does not automatically clear incremental backup files. DataStax recommends setting up a process to clear incremental backup hard links each time a new snapshot is created.

cassandra.yaml

The location of the cassandra.yaml file depends on the type of installation:
Package installations /etc/dse/cassandra/cassandra.yaml
Tarball installations installation_location/resources/cassandra/conf/cassandra.yaml

Procedure

  1. Edit the cassandra.yaml configuration file on each node in the cluster and change the value of incremental_backups to true.
  2. Restart each node to recognize the change.