Adding an HTTPS Listener¶
Scenarios¶
HTTPS listeners are best suited for applications that require encrypted transmission. Load balancers decrypt HTTPS requests before routing them to backend servers, which then send the processed requests back to load balancers for encryption before they are sent to clients.
Constraints¶
Dedicated load balancers: If the listener protocol is HTTPS, the protocol of the backend server group can be HTTP or HTTPS.
Shared load balancers: If the listener protocol is HTTPS, the protocol of the backend server group is HTTP by default and cannot be changed.
If you only select network load balancing (TCP/UDP) for your dedicated load balancer, you cannot add an HTTPS listener to this load balancer.
Adding an HTTPS Listener to a Dedicated Load Balancer¶
Log in to the management console.
In the upper left corner of the page, click
and select the desired region and project.Hover on
in the upper left corner to display Service List and choose Network > Elastic Load Balancing.Locate the load balancer and click its name.
Under Listeners, click Add Listener. Configure the parameters based on Table 1.
Table 1 Parameters for configuring a listener¶ Parameter
Description
Example Value
Name
Specifies the listener name.
listener-pnqy
Frontend Protocol
Specifies the protocol that will be used by the load balancer to receive requests from clients.
HTTPS
Frontend Port
Specifies the port that will be used by the load balancer to receive requests from clients.
The port number ranges from 1 to 65535.
80
SSL Authentication
Specifies whether how you want the clients and backend servers to be authenticated.
There are two options: One-way authentication or Mutual authentication.
If only server authentication is required, select One-way authentication.
If you want the clients and the load balancer to authenticate each other, select Mutual authentication. Only authenticated clients will be allowed to access the load balancer.
One-way authentication
Server Certificate
Specifies the certificate that will be used by the backend server to authenticate the client when HTTPS is used as the frontend protocol.
Both the certificate and private key are required.
For details, see Creating, Modifying, or Deleting a Certificate.
N/A
CA Certificate
Specifies the certificate that will be used by the backend server to authenticate the client when HTTPS is used as the frontend protocol.
A CA certificate is issued by a certificate authority (CA) and used to verify the certificate issuer. If HTTPS mutual authentication is required, HTTPS connections can be established only when the client provides a certificate issued by a specific CA.
For details, see Creating, Modifying, or Deleting a Certificate.
N/A
Enable SNI
Specifies whether to enable SNI when HTTPS is used as the frontend protocol.
SNI is an extension to TLS and is used when a server uses multiple domain names and certificates.
This allows the client to submit the domain name information while sending an SSL handshake request. After the load balancer receives the request, the load balancer queries the corresponding certificate based on the domain name and returns it to the client. If no certificate is found, the load balancer will return the default certificate. For details, see SNI Certificate (for HTTPS Listeners).
N/A
SNI Certificate
Specifies the certificate associated with the domain name when the frontend protocol is HTTPS and SNI is enabled.
Select an existing certificate or create one.
For details, see Creating, Modifying, or Deleting a Certificate.
N/A
Advanced Settings
Access Policy
Specifies how access to the listener is controlled. The following options are available (for details, see Access Control):
All IP addresses
Blacklist
Whitelist
Whitelist
IP Address Group
Specifies the IP address group associated with a whitelist or blacklist. If there is no IP address group, create one first. For more information, see Creating an IP Address Group.
ipGroup-b2
Advanced Forwarding
Specifies whether to enable the advanced forwarding policy. You can add advanced forwarding policies to HTTP or HTTPS listeners to forward requests to different backend server groups based on HTTP request method, HTTP header, query string, or CIDR block in addition to domain names and URLs.
Enabled
Security Policy
Specifies the security policy you can use if you select HTTPS as the frontend protocol. For more information, see TLS Security Policy.
TLS-1-0
HTTP/2
Specifies whether you want to use HTTP/2 if you select HTTPS for Frontend Protocol. For details, see HTTP/2.
N/A
Transfer Load Balancer EIP
Specifies whether to store the EIP bound to the load balancer in the X-Forwarded-ELB-IP header field and pass this field to backend servers.
N/A
Idle Timeout
Specifies the length of time for a connection to keep alive, in seconds. If no request is received within this period, the load balancer closes the connection and establishes a new one with the client when the next request arrives.
The idle timeout duration ranges from 0 to 4000.
60
Request Timeout
Specifies the length of time (in seconds) after which the load balancer closes the connection if the load balancer does not receive a request from the client.
The request timeout duration ranges from 1 to 300.
60
Response Timeout
Specifies the length of time (in seconds) after which the load balancer sends a 504 Gateway Timeout error to the client if the load balancer receives no response from the backend server after routing a request to the backend server and receives no response after attempting to route the same request to other backend servers.
The request timeout duration ranges from 1 to 300.
Note
If you have enabled sticky sessions and the backend server does not respond within the response timeout duration, the load balancer returns 504 Gateway Timeout to the clients.
60
Tag
Adds tags to the listener. Each tag is a key-value pair, and the tag key is unique.
N/A
Description
Provides supplementary information about the listener.
You can enter a maximum of 255 characters.
N/A
Click Next: Configure Request Routing Policy.
You are advised to select an existing backend server group.
You can also click Create new to create a backend server group and configure parameters as described in Table 2.
Table 2 Parameters for configuring a backend server group¶ Parameter
Description
Example Value
Backend Server Group
Specifies a group of servers with the same features to receive requests from the load balancer. Two options are available:
Create new
Use existing
Note
To associate an existing backend server group, ensure that it is not in use. Select the backend server group with the correct protocol. For example, if the frontend protocol is TCP, the backend protocol must be TCP.
Create new
Backend Server Group Name
Specifies the name of the backend server group.
server_group-sq4v
Backend Protocol
Specifies the protocol that will be used by backend servers to receive requests.
The backend protocol can be HTTP or HTTPS and changed be changed between the two options.
HTTP
Load Balancing Algorithm
Specifies the algorithm that will be used by the load balancer to distribute traffic. The following options are available:
Weighted round robin: Requests are routed to different servers based on their weights, which indicate server processing performance. Backend servers with higher weights receive proportionately more requests, whereas equal-weighted servers receive the same number of requests.
Weighted least connections: In addition to the number of active connections established with each backend server, each server is assigned a weight based on their processing capability. Requests are routed to the server with the lowest connections-to-weight ratio.
Source IP hash: The source IP address of each request is calculated using the consistent hashing algorithm to obtain a unique hash key, and all backend servers are numbered. The generated key is used to allocate the client to a particular server. This allows requests from different clients to be routed based on source IP addresses and ensures that a client is directed to the same server that it was using previously.
Note
Choose an appropriate algorithm based on your requirements for better traffic distribution.
For Weighted round robin or Weighted least connections, no requests will be routed to a server with a weight of 0.
Weighted round robin
Sticky Session
Specifies whether to enable sticky sessions. If you enable sticky sessions, all requests from a client during one session are sent to the same backend server.
This parameter is optional and can be enabled only if you have selected Weighted round robin for Load Balancing Algorithm.
N/A
Sticky Session Type
Specifies the type of sticky sessions for HTTP and HTTPS listeners.
Load balancer cookie: The load balancer generates a cookie after receiving a request from the client. All subsequent requests with the same cookie are routed to the same backend server.
Load balancer cookie
Stickiness Duration (min)
Specifies the minutes that sticky sessions are maintained. You can enable sticky sessions only if you select Weighted round robin for Load Balancing Algorithm.
Stickiness duration at Layer 4: 1 to 60
Stickiness duration at Layer 7: 1 to 1440
20
Slow Start
Specifies whether to enable slow start, which is disabled by default.
After you enable slow start, the load balancer linearly increases the proportion of requests to send to backend servers in this mode. When the slow start duration elapses, the load balancer sends full share of requests to backend servers and exits the slow start mode.
For details, see Configuring Slow Start (Dedicated Load Balancers).
N/A
Slow Start Duration
Specifies how long the slow start will last.
The duration ranges from 30 to 1200, in seconds, and the default value is 30.
30
Description
Provides supplementary information about the backend server group.
You can enter a maximum of 255 characters.
N/A
Click Next: Add Backend Server. Add backend servers and configure the health check for the backend server group. For details about how to add backend servers, see Adding or Removing Backend Servers (Dedicated Load Balancers). For details about how to configure health check parameters, see Table 3.
Table 3 Parameters for configuring a health check¶ Parameter
Description
Example Value
Health Check
Specifies whether to enable health checks.
N/A
Protocol
Specifies the protocol that will be used by the load balancer to check the health of backend servers. There are three options: TCP, HTTP, and HTTPS.
HTTP
Domain Name
Specifies the domain name that will be used for health checks. This parameter is available when you set the health check protocol to HTTP or HTTPS.
The domain name can contain digits, letters, hyphens (-), and periods (.), and must start with a digit or letter. The field is left blank by default and must start with a digit or letter.
www.elb.com
Port
Specifies the port that will be used by the load balancer to check the health of backend servers. The port number ranges from 1 to 65535.
Note
This parameter is optional. If you do not specify a health check port, a port of the backend server will be used for health checks by default. If you specify a port, it will be used for health checks.
80
Check Path
Specifies the health check URL, which is the destination on backend servers for health checks. This parameter is available only when you set the health check protocol to HTTP or HTTPS. The path must start with a slash (/) and can contain 1 to 80 characters.
The path can contain letters, digits, hyphens (-), slashes (/), periods (.), percent signs (%), ampersands (&), and the following special characters:
_~';@$*+,=!:()Note
Example:
If the URL is http://www.example.com/chat/try/, the health check path is /chat/try/.
If the URL is http://192.168.63.187:9096/chat/index.html, the health check path is /chat/index.html.
/index.html
Advanced Settings
Interval (s)
Specifies the maximum time between two consecutive health checks, in seconds.
The interval ranges from 1 to 50.
5
Timeout (s)
Specifies the maximum time required for waiting for a response from the health check, in seconds. The timeout duration ranges from 1 to 50.
3
Maximum Retries
Specifies the maximum number of health check retries. The value ranges from 1 to 10.
3
Click Next: Confirm.
Confirm the configuration and click Submit.
Adding an HTTPS Listener to a Shared Load Balancer¶
Log in to the management console.
In the upper left corner of the page, click
and select the desired region and project.Hover on
in the upper left corner to display Service List and choose Network > Elastic Load Balancing.Locate the load balancer and click its name.
Under Listeners, click Add Listener. Configure the parameters based on Table 4.
Table 4 Parameters for configuring a listener for a shared enhanced load balancer¶ Parameter
Description
Example Value
Name
Specifies the listener name.
listener-pnqy
Frontend Protocol
Specifies the protocol that will be used by the load balancer to receive requests from clients.
HTTPS
Frontend Port
Specifies the port that will be used by the load balancer to receive requests from clients.
The port number ranges from 1 to 65535.
80
SSL Authentication
Specifies whether how you want the clients and backend servers to be authenticated.
There are two options: One-way authentication or Mutual authentication.
If only server authentication is required, select One-way authentication.
If you want the clients and the load balancer to authenticate each other, select Mutual authentication. Only authenticated clients will be allowed to access the load balancer.
One-way authentication
CA Certificate
Specifies the certificate used by the server to authenticate the client when HTTPS is used as the frontend protocol.
For details, see Creating, Modifying, or Deleting a Certificate.
N/A
Server Certificate
Specifies the certificate used by the server to authenticate the client when HTTPS is used as the frontend protocol.
Both the certificate and private key are required.
For details, see Creating, Modifying, or Deleting a Certificate.
N/A
Enable SNI
Specifies whether to enable SNI when HTTPS is used as the frontend protocol.
SNI is an extension to TLS and is used when a server uses multiple domain names and certificates.
This allows the client to submit the domain name information while sending an SSL handshake request. After the load balancer receives the request, the load balancer queries the corresponding certificate based on the domain name and returns it to the client. If no certificate is found, the load balancer will return the default certificate. For details, see SNI Certificate (for HTTPS Listeners).
N/A
SNI Certificate
Specifies the certificate associated with the domain name when the frontend protocol is HTTPS and SNI is enabled.
Select an existing certificate or create one.
For details, see Creating, Modifying, or Deleting a Certificate.
N/A
Advanced Settings
Access Policy
Specifies how access to the listener is controlled. The following options are available (for details, see Access Control):
All IP addresses
Blacklist
Whitelist
Whitelist
IP Address Group
Specifies the IP address group associated with a whitelist or blacklist. If there is no IP address group, create one first. For more information, see Creating an IP Address Group.
ipGroup-b2
HTTP/2
Specifies whether you want to use HTTP/2 if you select HTTPS for Frontend Protocol. For details, see HTTP/2.
N/A
Security Policy
Specifies the security policy you can use if you select HTTPS as the frontend protocol. There are four options. For more information, see TLS Security Policy.
TLS-1-2
Transfer Load Balancer EIP
Specifies whether to store the EIP bound to the load balancer in the X-Forwarded-ELB-IP header field and pass this field to backend servers.
Enable this option if you want to transparently transmit the EIP of the load balancer to backend servers.
N/A
Idle Timeout
Specifies the length of time for a connection to keep alive, in seconds. If no request is received within this period, the load balancer closes the connection and establishes a new one with the client when the next request arrives.
The idle timeout duration ranges from 0 to 4000.
60
Request Timeout
Specifies the length of time (in seconds) after which the load balancer closes the connection if the load balancer does not receive a request from the client.
The request timeout duration ranges from 1 to 300.
60
Response Timeout
Specifies the length of time (in seconds) after which the load balancer sends a 504 Gateway Timeout error to the client if the load balancer receives no response from the backend server after routing a request to the backend server and receives no response after attempting to route the same request to other backend servers.
The request timeout duration ranges from 1 to 300.
Note
If you have enabled sticky sessions and the backend server does not respond within the response timeout duration, the load balancer returns 504 Gateway Timeout to the clients.
60
Tag
Adds tags to the listener. Each tag is a key-value pair, and the tag key is unique.
N/A
Description
Provides supplementary information about the listener.
You can enter a maximum of 255 characters.
N/A
Click Next: Configure Request Routing Policy. Table 5 describes the parameters for configuring a backend server group.
Table 5 Parameters for adding a backend server group¶ Parameter
Description
Example Value
Backend Server Group
Specifies a group of servers with the same features to receive requests from the load balancer. Two options are available:
Create new
Use existing
Note
To associate an existing backend server group, ensure that it is not in use. Select the backend server group with the correct protocol. For example, if the frontend protocol is TCP, the backend protocol can only be TCP.
Create new
Backend Server Group Name
Specifies the name of the backend server group.
server_group-sq4v
Backend Protocol
Specifies the protocol used by backend servers to receive requests.
The backend protocol is HTTP by default and cannot be changed.
HTTP
Load Balancing Algorithm
Specifies the algorithm used by the load balancer to distribute traffic. The following options are available:
Weighted round robin: Requests are routed to different servers based on their weights, which indicate server processing performance. Backend servers with higher weights receive proportionately more requests, whereas equal-weighted servers receive the same number of requests.
Weighted least connections: In addition to the number of active connections established with each backend server, each server is assigned a weight based on their processing capability. Requests are routed to the server with the lowest connections-to-weight ratio.
Source IP hash: The source IP address of each request is calculated using the consistent hashing algorithm to obtain a unique hash key, and all backend servers are numbered. The generated key is used to allocate the client to a particular server. This allows requests from different clients to be routed based on source IP addresses and ensures that a client is directed to the same server that it was using previously.
Note
Choose an appropriate algorithm based on your requirements for better traffic distribution.
For Weighted round robin or Weighted least connections, no requests will be routed to a server with a weight of 0.
Weighted round robin
Sticky Session
Specifies whether to enable sticky sessions. If you enable sticky sessions, all requests from a client during one session are sent to the same backend server.
Note
You can enable sticky sessions only if you have selected Weighted round robin for Load Balancing Algorithm.
N/A
Sticky Session Type
Specifies the type of sticky sessions for HTTP and HTTPS listeners.
Load balancer cookie: The load balancer generates a cookie after receiving a request from the client. All subsequent requests with the same cookie are routed to the same backend server.
Application cookie: The application deployed on the backend server generates a cookie after receiving the first request from the client. All subsequent requests with the same cookie are routed to the same backend server.
Load balancer cookie
Cookie Name
Specifies the cookie name. If you select Application cookie, enter a cookie name.
cookieName-qsps
Description
Provides supplementary information about the backend server group.
You can enter a maximum of 255 characters.
N/A
Click Next: Add Backend Server. Add backend servers and configure the health check for the backend server group. For details about how to add backend servers, see Adding or Removing Backend Servers (Shared Load Balancers). For details about how to configure health check parameters, see Table 6.
Table 6 Parameters for configuring a health check¶ Parameter
Description
Example Value
Health Check
Specifies whether to enable health checks.
N/A
Protocol
Specifies the protocol that will be used by the load balancer to check the health of backend servers. There are two options: TCP and HTTP.
HTTP
Domain Name
Specifies the domain name that will be used for health checks.
The domain name can contain digits, letters, hyphens (-), and periods (.). The field is left blank by default and must start with a digit or letter.
This parameter is available when you set the health check protocol to HTTP.
www.elb.com
Port
Specifies the port that will be used by the load balancer to check the health of backend servers. The port number ranges from 1 to 65535.
Note
This parameter is optional. If you do not specify a health check port, a port of the backend server will be used for health checks by default. If you specify a port, it will be used for health checks.
80
Check Path
Specifies the health check URL, which is the destination on backend servers for health checks. This parameter is available only when the health check protocol is HTTP. The path must start with a slash (/) and can contain 1 to 80 characters.
The path can contain letters, digits, hyphens (-), slashes (/), periods (.), percent signs (%), ampersands (&), and the following special characters:
_~';@$*+,=!:()Note
Example:
If the URL is http://www.example.com/chat/try/, the health check path is /chat/try/.
If the URL is http://192.168.63.187:9096/chat/index.html, the health check path is /chat/index.html.
/index.html
Advanced Settings
Interval (s)
Specifies the maximum time between two consecutive health checks, in seconds.
The interval ranges from 1 to 50.
5
Timeout (s)
Specifies the maximum time required for waiting for a response from the health check, in seconds. The timeout duration ranges from 1 to 50.
3
Maximum Retries
Specifies the maximum number of health check retries. The value ranges from 1 to 10.
3
Click Next: Confirm.
Confirm the configuration and click Submit.