Configuring Health Check for Multiple Ports¶
The annotation field related to the health check of the LoadBalancer Service is upgraded from Kubernetes.io/elb.health-check-option to Kubernetes.io/elb.health-check-options. Each Service port can be configured separately, and you can configure only some ports. If the port protocol does not need to be configured separately, the original annotation field is still available and does not need to be modified.
Constraints¶
This feature takes effect only in the following versions:
v1.19: v1.19.16-r5 or later
v1.21: v1.21.8-r0 or later
v1.23: v1.23.6-r0 or later
v1.25: v1.25.2-r0 or later
kubernetes.io/elb.health-check-option and kubernetes.io/elb.health-check-options cannot be configured at the same time.
The target_service_port field is mandatory and must be unique.
For a TCP port, the health check protocol can only be TCP or HTTP. For a UDP port, the health check protocol must be UDP.
Procedure¶
The following is an example of using the kubernetes.io/elb.health-check-options annotation:
apiVersion: v1
kind: Service
metadata:
name: nginx
namespace: default
labels: {}
annotations:
kubernetes.io/elb.class: union
kubernetes.io/elb.id: 038ffbda-bd3a-48bb-8b8c-a8582601fd97
kubernetes.io/elb.lb-algorithm: ROUND_ROBIN
kubernetes.io/elb.health-check-flag: 'on'
kubernetes.io/elb.health-check-options: '{
"target_service_port": "TCP:80", // (Mandatory) Port for health check specified by spec.ports. The value consists of the protocol and port number, for example, TCP:80.
"monitor_port": "", // (Optional) Re-specified port for health check. If this parameter is not specified, the service port is used by default. Ensure that the port is in the listening state on the node where the pod is located. Otherwise, the health check result will be affected.
"protocol":"TCP",
"delay":"5",
"timeout":"10",
"max_retries":"3",
"path":"/"
}'
spec:
selector: {}
externalTrafficPolicy: Cluster
ports:
- name: cce-service-0
targetPort: 80
nodePort: 0
port: 80
protocol: TCP
type: LoadBalancer
loadBalancerIP: **.**.**.**
Parameter | Mandatory | Type | Description |
|---|---|---|---|
target_service_port | Yes | String | Port for health check specified by spec.ports. The value consists of the protocol and port number, for example, TCP:80. |
monitor_port | No | String | Re-specified port for health check. If this parameter is not specified, the service port is used by default. Note Ensure that the port is in the listening state on the node where the pod is located. Otherwise, the health check result will be affected. |
delay | No | String | Initial waiting time (in seconds) for starting the health check. Value range: 1 to 50. Default value: 5 |
timeout | No | String | Health check timeout, in seconds. Value range: 1 to 50. Default value: 10 |
max_retries | No | String | Maximum number of health check retries. Value range: 1 to 10. Default value: 3 |
protocol | No | String | Health check protocol. Default value: protocol of the associated Service Value options: TCP, UDP, or HTTP |
path | No | String | Health check URL. This parameter needs to be configured when the protocol is HTTP. Default value: / The value can contain 1 to 10,000 characters. |