management.rst

Service Management

This section shows how a deployed VS stack can be interacted with.

Scaling

Scaling is a handy tool to ensure stable performance, even when dealing with higher usage on either service. For example, the preprocessor and registrar can be scaled to a higher replica count to enable a better throughput when ingesting data into the VS.

The following command scales the renderer service to 5 replicas:

docker service scale <stack-name>_renderer=5

A service can also be scaled to zero replicas, effectively disabling the service.

Warning

The redis and database should never be scaled (their replica count should remain 1) as this can lead to service disruptions and corrupted data.

Updating Images

Updating the service software is done using previously established tools. To update the service in question, it needs to be scaled to zero replicas. Then the new image can be pulled, and the service can be scaled back to its original value. This forces the start of the service from the newly fetched image.