Setting Up Replication
This example will guide you through setting up replication of a database. These instructions assume that you have two SingleStoreDB clusters running; the primary cluster contains the source data that is replicated to the secondary cluster.
Note
To replicate a database, the secondary cluster user must have CREATE DATABASE
privileges and the primary cluster user (the one specified in REPLICATE DATABASE
) must have the ALL PRIVILEGES
permission on the primary cluster’s master aggregator.
The following host:port
combinations represent the master aggregators of the primary and secondary clusters:
primary-MA:3306
secondary-MA:3306
Note that the primary and secondary clusters need not have identical topologies. SingleStoreDB will automatically manage sharding of replica data on the secondary cluster. It is not necessary to use the root user for this command, instead use another user with sufficient permissions as listed above.
To begin replicating the database db_name
from primary-MA
, run the following command on secondary-MA
:
REPLICATE DATABASE db_name FROM master_user:'master_user_password'@primary-MA:3306;
You always initiate replication from the secondary cluster. You can start replication to a secondary cluster without pausing the primary cluster.
Multiple secondary clusters can replicate from a single primary cluster. To do this, run REPLICATE DATABASE
on the master aggregator of each of the replica clusters.
Note
Data is always replicated across clusters asynchronously. Databases are replicated at the leaf level, which implies that a leaf in the secondary cluster replicates data directly from a leaf in the primary cluster; therefore, when connecting a secondary cluster to the primary cluster, the leaves in the primary and secondary cluster must be able to communicate with each other. They should not be blocked by firewall or network rules.