HTTPProxy weighted services - healthchecks #7358
Description
Hello,
I have config for HTTPProxy with weighted services like below:
apiVersion: projectcontour.io/v1
kind: HTTPProxy
metadata:
name: example-proxy
spec:
virtualhost:
fqdn: some.host.test
routes:
- conditions:
- prefix: /
healthCheckPolicy:
path: /chealth
intervalSeconds: 5
timeoutSeconds: 2
unhealthyThresholdCount: 3
healthyThresholdCount: 2
host: other.host.test
services:
- name: service-1
port: 443
protocol: tls
weight: 70
requestHeadersPolicy:
set:
- name: Host
value: other.host.test
- name: service-2
port: 443
weight: 30
protocol: tls
requestHeadersPolicy:
set:
- name: Host
value: other.host.testWhen one of the service is not available (the health-check does not succeeded), the traffic is still forwarded to unhealthy service, even the envoy marked the service as unhealthy:
example-proxy/service-1/443/ddc01a37e7::X.X.X.X:443::health_flags::/failed_active_hc
example-proxy/service-2/443/ddc01a37e7::Y.Y.Y.Y:443::health_flags::healthyI assume because the services are mapped to weighted_cluster in envoy config:
"virtual_hosts": [
{
"name": "some.host.test",
"domains": [
"some.host.test"
],
"routes": [
{
"match": {
"prefix": "/"
},
"route": {
"weighted_clusters": {
"clusters": [
{
"name": "example-proxy/service-1/443/ddc01a37e7:",
"weight": 70,
"host_rewrite_literal": "other.host.test"
},
{
"name": "example-proxy/service-2/443/ddc01a37e7",
"weight": 30,
"host_rewrite_literal": "other.host.test"
}
]
}
},And tests are performed by Envoy not on weighted_clusters level to check health of them and deactivate it from route, but tests are performed on cluster level to filter out unhealthy Endpoin/EndpointSlices.
So the loadbalacing decision is pure made on weight and does not account the health status.
The question is then, is there any solution for contour to overcome this one, to automatically filter out service from traffic forward if not healthy ?
I think this kind of behaviour could be solved by implementing it on top of Aggregated cluster functionality on Envoy side with locality_weighted_lb_config, are there maybe plan to implement this on contour side ?
Environment:
- Contour version: 1.33.0
- Kubernetes version: (use
kubectl version): 1.34 - Cloud provider or hardware configuration: kind/local