Administering a Cluster min read


Info

Except for the SHOW ... commands, SingleStore Managed Service does not support the commands mentioned in this topic.

Before proceeding, learn the key concepts that are necessary for understanding how to administer a SingleStore DB environment.

SingleStore DB’s distributed architecture provides commands and settings used to manage a SingleStore DB cluster.

Cluster Administration Commands

Setting the Redundancy Level

To use Availability Groups in a cluster, you need to set the redundancy level, which specifies the maximum number (1 or 2) of availability groups. By default, this is set to 1. There are two ways in which to change the redundancy level.

Setting the Engine Variable

One way is to use the SET GLOBAL command to change redundancy_level engine variable on the master aggregator at runtime (see Setting the Redundancy Level):

memsql> SET @@GLOBAL.redundancy_level = {1 | 2};

You can inspect the current value with the SELECT GLOBAL command:

memsql> SELECT @@GLOBAL.redundancy_level;

Adding and Removing Leaves

Use ADD LEAF and REMOVE LEAF to add leaves to, and remove leaves from, a SingleStore DB cluster.

Adding and Removing Child Aggregators

Use ADD AGGREGATOR and REMOVE AGGREGATOR to add and remove child aggregators from a SingleStore DB cluster.

Info

These commands must be run against the Master Aggregator.