A CTERA Portal installation comprises a cluster of one or more servers. Each server can host any combination of the following services:
Main database - Only one server can host the main database. The server that hosts the main database is called the master server.
Catalog Node – A database service that stores file metadata. After installation, this service can be enabled or disabled on each server through the CTERA Portal web interface. For details, see the CTERA Portal Administration Guide.
CTERA FS storage node – This service stores blocks. If an external object storage system is used (such as EMC Atmos or Amazon S3), this service is handled externally and not required. Storage nodes are defined through the CTERA Portal web interface.
Application service - This service accepts connections from web and CTTP clients. After installation, this service can be enabled or disabled on each server through the CTERA Portal web interface. For details, see the CTERA Portal Administration Guide.
By default, the first installed server is a master server, hosting the main database, application server, and catalog node. In the simplest topology, there is only one server, which hosts all four services. Optionally, you can install any number of secondary servers, for scalability and load balancing (see Scalability and Load Balancing) and for data replication (see Data Replication and Failover).