Work with snapshots

In this section, you learn how to work with the default snapshot configuration that is enabled on ever cluster and how to take manual snapshots of your own.

Create a manual snapshot

You should create a snapshot before making any changes to the environment, loading a large amount of new data, or changing the structure of a table. You can have up to 20 manual snapshots at a time, after which, you have to clear one before you are able to create another. If you need to delete a snapshot, contact ThoughtSpot Support.

Taking a snapshot is fast, about 20 seconds. It happens invisibly in the background of a running cluster. If you would like to restore from a snapshot instead, contact ThoughtSpot Support.

To create a snapshot:

1. Log in to the Linux shell using SSH.

2. Initiate a snapshot, providing a name and reason for creating it: Snapshot names must be 44 characters or less.

    $ tscli snapshot create <snapshot_name> <reason>
   

3. Check that the snapshot was created:

    $ tscli snapshot ls
   

Configure periodic snapshots

By default, each ThoughtSpot cluster is configured to take automatic, periodic snapshots of your cluster. This section explains how to learn more about the periodic snapshots in your cluster.

The default snapshot policy is enabled for every cluster. You can use the tscli snapshot-policy show command to display the current policy for periodic snapshots.

$ tscli snapshot-policy show
schedule {
    period {
        number: 1
        unit: HOUR
        }
        retention_policy {
            bucket {
                time {
                    number: 1
                    unit: HOUR
            }
            capacity: 3
            }
            bucket {
                time {
                    number: 4
                    unit: HOUR
            }
            capacity: 2
            }
    }
    offset_minutes_from_sunday_midnight: 0
}
enabled: true

This policy takes a snapshot every hour starting at midnight on Sunday. It retains the snapshots from the last three hour intervals and two snapshots from two of the previous 4 hour intervals. That means, there are 5 periodic snapshots retained overall. For detailed information about understanding the schedule, see Understand backup/snapshot schedules.

You shouldn’t change this default policy unless instructed to by support. If you have to adjust it for some reason, you can use, tscli snapshot-policy update command. This opens the current policy in an editor. Your policy should never retain more than 20 snapshots at any point in time. Exceeding this number can impact cluster performance.

You cannot delete the snapshot policy. However, you can disable the policy by executing thetscli snapshot-policy disable command. And you can re-enable it by running, tscli snapshot-policy enable.

CAUTION: Backups rely on the snapshot system. For this reason, you should never disable the periodic snapshot system. For example, if you have disabled the periodic snapshots and periodic backups are enabled, then the periodic backup may use a very outdated snapshot or it may fail all together.

To check your current periodic snapshot policy:

1. Log in to the Linux shell using SSH.
2. Enter tscli snapshot-policy show to view the policy.