Configuring Timeout for a LoadBalancer Service¶
LoadBalancer Services allow you to configure timeout, which is the maximum duration for keeping a connection if no request is received from the client. If no request is received during this period, the load balancer closes the connection and establishes a new one with the client when the next request arrives.
Notes and Constraints¶
The following table lists the scenarios where timeout can be configured for a Service.
Timeout Type
Load Balancer Type
Restrictions
Supported Cluster Version
Idle timeout
Dedicated
None
v1.19: v1.19.16-r30 or later
v1.21: v1.21.10-r10 or later
v1.23: v1.23.8-r10 or later
v1.25: v1.25.3-r10 or later
Other clusters of later versions
Idle timeout
Shared
UDP is not supported.
v1.23: v1.23.13-r0 or later
v1.25: v1.25.8-r0 or later
v1.27: v1.27.5-r0 or later
v1.28: v1.28.3-r0 or later
Other clusters of later versions
Request timeout
Dedicated and shared
Only HTTP and HTTPS are supported.
Response timeout
Dedicated and shared
Only HTTP and HTTPS are supported.
After timeout is configured, if you delete the timeout configuration on the CCE console or delete the target annotation from the YAML file, the configuration on the ELB will be retained.
Using the CCE Console¶
Log in to the CCE console and click the cluster name to access the cluster console.
In the navigation pane, choose Services & Ingresses. In the upper right corner, click Create Service.
Configure Service parameters. In this example, only mandatory parameters required for configuring timeout are listed. For details about how to configure other parameters, see Creating a LoadBalancer Service.
Service Name: Specify a Service name, which can be the same as the workload name.
Service Type: Select LoadBalancer.
Selector: Add a label and click Confirm. The Service will use this label to select pods. You can also click Reference Workload Label to use the label of an existing workload. In the dialog box that is displayed, select a workload and click OK.
Load Balancer: Select a load balancer type and creation mode.
A load balancer can be dedicated or shared.
This section uses an existing load balancer as an example. For details about the parameters for automatically creating a load balancer, see Table 1.
Ports
Protocol: protocol that the load balancer complies. Timeout cannot be configured for a UDP-compliant shared load balancer.
Service Port: port used by the Service. The port number ranges from 1 to 65535.
Container Port: listener port of the workload. For example, Nginx uses port 80 by default.
Frontend Protocol: Select a protocol for the listener. If HTTP/HTTPS is not enabled, only the idle timeout can be configured.
Listener
Advanced Options: Select a proper option.
Configuration
Description
Restrictions
Idle Timeout
Timeout for an idle client connection. If there are no requests reaching the load balancer during the timeout duration, the load balancer will disconnect the connection from the client and establish a new connection when there is a new request.
This configuration is not supported if the port of a shared load balancer uses UDP.
Request Timeout
Timeout for waiting for a request from a client. There are two cases:
If the client fails to send a request header to the load balancer during the timeout duration, the request will be interrupted.
If the interval between two consecutive request bodies reaching the load balancer is greater than the timeout duration, the connection will be disconnected.
This parameter is available only after HTTP/HTTPS is enabled on ports.
Response Timeout
Timeout for waiting for a response from a backend server. After a request is forwarded to the backend server, if the backend server does not respond during the timeout duration, the load balancer will stop waiting and return HTTP 504 Gateway Timeout.
This parameter is available only after HTTP/HTTPS is enabled on ports.
Click OK.
Using kubectl¶
Use annotations to configure timeout. The following shows an example:
apiVersion: v1
kind: Service
metadata:
annotations:
kubernetes.io/elb.id: <your_elb_id> # In this example, an existing dedicated load balancer is used. Replace its ID with the ID of your dedicated load balancer.
kubernetes.io/elb.class: performance # Load balancer type
kubernetes.io/elb.keepalive_timeout: '300' # Timeout setting for client connections
kubernetes.io/elb.client_timeout: '60' # Timeout for waiting for a request from a client
kubernetes.io/elb.member_timeout: '60' # Timeout for waiting for a response from a backend server
name: nginx
spec:
ports:
- name: service0
port: 80
protocol: TCP
targetPort: 80
selector:
app: nginx
type: LoadBalancer
Parameter | Mandatory | Type | Description |
|---|---|---|---|
kubernetes.io/elb.keepalive_timeout | No | String | Timeout for client connections. If there are no requests reaching the load balancer during the timeout duration, the load balancer will disconnect the connection from the client and establish a new connection when there is a new request. Value:
|
kubernetes.io/elb.client_timeout | No | String | Timeout for waiting for a request from a client. There are two cases:
The value ranges from 1 to 300 (in seconds). The default value is 60. |
kubernetes.io/elb.member_timeout | No | String | Timeout for waiting for a response from a backend server. After a request is forwarded to the backend server, if the backend server does not respond within the duration specified by member_timeout, the load balancer will stop waiting and return HTTP 504 Gateway Timeout. The value ranges from 1 to 300 (in seconds). The default value is 60. |