ClickHouse cluster node settings

Prior to storage creation, carefully plan the cluster structure and deploy the necessary network infrastructure. When choosing a ClickHouse cluster configuration, consider the specific event storage requirements of your organization.

When creating ClickHouse cluster nodes, verify the network connectivity of the system and open the ports used by the components.

For each node of the ClickHouse cluster, you need to specify the following settings:

• Fully qualified domain name (FQDN)—a unique address to access the node. Specify the entire FQDN, for example, kuma-storage.example.com.
• Shard, replica, and keeper IDs—the combination of these settings determines the position of the node in the ClickHouse cluster structure and the node role.

Node roles

The roles of the nodes depend on the specified settings:

• shard, replica, keeper—the node participates in the accumulation and search of normalized KUMA events and helps coordinate data replication at the cluster-wide level.
• shard, replica—the node participates in the accumulation and search of normalized KUMA events.
• keeper—the node does not accumulate normalized events, but helps coordinate data replication at the cluster-wide level. Dedicated keepers must be specified at the beginning of the list in the Resources → Storages → <Storage> → Basic settings → ClickHouse cluster nodes section.

ID requirements:

• If multiple shards are created in the same cluster, the shard IDs must be unique within this cluster.
• If multiple replicas are created in the same shard, the replica IDs must be unique within this shard.
• The keeper IDs must be unique within the cluster.

Example of ClickHouse cluster node IDs:

• shard 1, replica 1, keeper 1;
• shard 1, replica 2;
• shard 2, replica 1;
• shard 2, replica 2, keeper 3;
• shard 2, replica 3;
• keeper 2.