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Load-Balancing
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Monitors

A monitor issues health checks at regular intervals to evaluate the health of an origin pool . When a pool becomes unhealthy , your load balancer takes that pool out of the server rotation.

Dynamic load balancing involves pools, origins, monitors, and health checks

Health checks that result in a status change for an origin server are recorded as events in the Load Balancing event logs.


Properties

For an up-to-date list of monitor properties, refer to Monitor properties in our API documentation.


Create monitors

For step-by-step guidance, refer to Create monitors .


Host header prioritization

When a load balancer runs health checks, headers set on an origin override headers set on a monitor. For more details, refer to Override HTTP Host headers .


API commands

The Cloudflare API supports the following commands for monitors. Examples are given for user-level endpoint but apply to the account-level endpoint as well.

CommandMethodEndpoint
Create MonitorPOSTuser/load_balancers/monitors
Delete MonitorDELETEuser/load_balancers/monitors
List MonitorsGETuser/load_balancers/monitors
Monitor DetailsGETuser/load_balancers/monitors/:identifier
Update MonitorPUTuser/load_balancers/monitors
Preview MonitorPOSTuser/load_balancers/monitors/:identifier/preview