The load status that servers send back when using the REST API can be viewed in the cOS Core web interface by going to the Server Load Balancing Status page of the interface. An example screenshot of this page with the REST API in operation is shown below.

If a server did not send a Post message within the last minute, the Errors column in the above screenshot would have shown the value REST for that server.

The Pause button in the Maintenance column of this WebUI display can be used to remove a server from being available for connection distribution. However, the server itself will not be aware when this is done and this is also independent from the API. Any existing connections to a server will not be closed by cOS Core when the pause button is pushed for that server.

However, note that new connections could still be allocated to a paused server in order to to comply with the requirement for SLB stickiness, if stickiness is enabled. Stickiness is explained further in the SLB section of the separate cOS Core Administration Guide.