Host roles in Managed Service for OpenSearch

Each Managed Service for OpenSearch cluster consists of one or more host groups of the OpenSearch and Dashboards (optional) types:

• An OpenSearch host group may contain hosts with the DATA or MANAGER roles. If a cluster has a single OpenSearch group, its hosts will have both roles.

• A Dashboards host group may only contain hosts with the DASHBOARDS role.

Hosts with the DATA roleHosts with the DATA role

Hosts with this role store one or more indexes and handle search, write, and analysis queries. To ensure index scalability and fault tolerance, configure sharding and replication for this index.

For fault tolerance reasons, you cannot create a cluster that only has two hosts with the DATA role. To make your cluster fault-tolerant, add a host group with the MANAGER role.

Hosts with the MANAGER roleHosts with the MANAGER role

Hosts with this role monitor the state of the cluster and manage its configuration, ensuring the performance of all OpenSearch components.

If you are using hosts with the MANAGER role, a group containing three such hosts will be added to the cluster.

If no hosts with the MANAGER role are used, this role will be supported by hosts with the DATA role. However, with dedicated hosts with the MANAGER role, you can increase the overall cluster reliability and reduce the load on hosts with the DATA role.

Hosts with the DASHBOARDS roleHosts with the DASHBOARDS role

Hosts with this role run OpenSearch Dashboards, a data visualization tool to use in such scenarios as real-time application monitoring, threat detection, incident management, or personalized search.