Services
This is a description of the services of Hitachi Content Platform for cloud scale, as well as how to view, configure, move, and repair services.
Services perform functions essential to the health or functionality of the system. For example, the Metrics service stores and manages system events, while the Watchdog service ensures that other services remain running. Internally, services run in Docker containers on the instances in the system.
Services are grouped into these categories depending on what actions they perform:
- Services — Enable product functionality. You can scale, move, and reconfigure these services.
- System services — Maintain the health and availability of the system. You cannot scale, move, or reconfigure these services.
Some system services run only on master instances.
Some services are classified as applications. These are the services with which users interact. Services that are not applications typically interact only with other services.
Services run on instances in the system. Most services can run simultaneously on multiple instances. That is, you can have multiple instances of a service running on multiple instances in the system. Some services run on only one instance.
Each service has a recommended and required number of instances on which it should run.
You can configure where Hitachi Content Platform for cloud scale services run, but not system services.
If a service supports floating, you have flexibility in configuring where new instances of that service are started when service instances fail.
Non-floating (or persistent) services run on the specific instances that you specify. If one of those service instances fails, the system does not automatically bring up a new instance of that service on another system instance.
With a service that supports floating, you specify a pool of eligible system instances and the number of service instances that should be running at any time. If a service instance fails, the system brings up another one on one of the system instances in the pool that doesn't already have an instance of that service running.
Each service binds to a number of ports and to one type of network, either internal or external. Networking for each service is configured during system installation and cannot be changed once a system is running.
Services can use volumes for storing data.