Runtime

Upstream clusters support the following runtime settings:

Active health checking

health_check.min_interval
Min value for the health checking interval. Default value is 0. The health checking interval will be between min_interval and max_interval.
health_check.max_interval
Max value for the health checking interval. Default value is MAX_INT. The health checking interval will be between min_interval and max_interval.
health_check.verify_cluster
What % of health check requests will be verified against the expected upstream service as the health check filter will write the remote service cluster into the response.

Outlier detection

See the outlier detection architecture overview for more information on outlier detection. The runtime parameters supported by outlier detection are the same as the static configuration parameters, namely:

outlier_detection.consecutive_5xx
consecutive_5XX setting in outlier detection
outlier_detection.consecutive_gateway_failure
consecutive_gateway_failure setting in outlier detection
outlier_detection.interval_ms
interval_ms setting in outlier detection
outlier_detection.base_ejection_time_ms
base_ejection_time_ms setting in outlier detection
outlier_detection.max_ejection_percent
max_ejection_percent setting in outlier detection
outlier_detection.enforcing_consecutive_5xx
enforcing_consecutive_5xx setting in outlier detection
outlier_detection.enforcing_consecutive_gateway_failure
enforcing_consecutive_gateway_failure setting in outlier detection
outlier_detection.enforcing_success_rate
enforcing_success_rate setting in outlier detection
outlier_detection.success_rate_minimum_hosts
success_rate_minimum_hosts setting in outlier detection
outlier_detection.success_rate_request_volume
success_rate_request_volume setting in outlier detection
outlier_detection.success_rate_stdev_factor
success_rate_stdev_factor setting in outlier detection

Core

upstream.healthy_panic_threshold
Sets the panic threshold percentage. Defaults to 50%.
upstream.use_http2
Whether the cluster utilizes the http2 feature if configured. Set to 0 to disable HTTP/2 even if the feature is configured. Defaults to enabled.

Zone aware load balancing

upstream.zone_routing.enabled
% of requests that will be routed to the same upstream zone. Defaults to 100% of requests.
upstream.zone_routing.min_cluster_size
Minimal size of the upstream cluster for which zone aware routing can be attempted. Default value is 6. If the upstream cluster size is smaller than min_cluster_size zone aware routing will not be performed.

Circuit breaking

circuit_breakers.<cluster_name>.<priority>.max_connections
Max connections circuit breaker setting
circuit_breakers.<cluster_name>.<priority>.max_pending_requests
Max pending requests circuit breaker setting
circuit_breakers.<cluster_name>.<priority>.max_requests
Max requests circuit breaker setting
circuit_breakers.<cluster_name>.<priority>.max_retries
Max retries circuit breaker setting