Healthcheck filters eliminate answers that are currently down or experiencing higher traffic than the limits you define.
The following healthcheck filters are available in Filter Chain:
| Filter | Description |
|---|---|
| Up | This filter eliminates answers in which the up metadata field is not true or 1, or if the up metadata field is not set. This filter is bypassed and all answers are returned if all answers are eliminated as a result of the filter. |
| Shed Load |
This filter drops answers in which the load is higher than the defined limits, resulting in slowed or stopped traffic to high-traffic or overloaded endpoints. You must select a metric type (load average, average connections, or active requests) and then define low and high watermark values for that metric. Typically, you configure a data feed to regularly update the load metrics associated with your answers. This filter does nothing if the load is below the configured low watermark. If the load is above the configured high watermark for an answer, the answer is eliminated. If the load is between the low and high watermarks, the answer is eliminated more often as the load approaches the high watermark. As load increases, the answer is returned less often. Refer to the Configuring automatic load shedding using the Shed Load filter article to learn more about how to use this filter. |