Server Load Balancer:UpdateServerGroupAttribute

The backend port that is used for health checks.

Valid values: 0 to 65535.

If you set the value to 0, the backend port is used for health checks.

Specifies whether to enable the health check feature. Valid values:

• true
• false

The domain name that is used for health checks.

• Backend Server Internal IP (default): Use the internal IP address of backend servers as the health check domain name.

• Custom Domain Name: Enter a domain name.

  • The domain name must be 1 to 80 characters in length.
  • The domain name can contain lowercase letters, digits, hyphens (-), and periods (.).
  • The domain name must contain at least one period (.) but cannot start or end with a period (.).
  • The rightmost domain label of the domain name can contain only letters, and cannot contain digits or hyphens (-).
  • The domain name cannot start or end with a hyphen (-).

The HTTP status codes that indicate healthy backend servers.

The HTTP version that is used for health checks. Valid values:

• HTTP1.0
• HTTP1.1

The interval at which health checks are performed. Unit: seconds.

Valid values: 1 to 50.

The HTTP method that is used for health checks. Valid values:

• GET: If the length of a response exceeds 8 KB, the response is truncated. However, the health check result is not affected.
• POST: gRPC health checks use the POST method by default.
• HEAD: HTTP and HTTPS health checks use the HEAD method by default.

The URL that is used for health checks.

The URL must be 1 to 80 characters in length, and can contain letters, digits, and the following special characters: - / . % ? # & =. It can also contain the following extended characters: _ ; ~ ! ( ) * [ ] @ $ ^ : ' , +. The URL must start with a forward slash (/).

The protocol that you want to use for health checks. Valid values:

• HTTP: HTTP health checks simulate browser behaviors by sending HEAD or GET requests to probe the availability of backend servers.
• HTTPS: HTTPS health checks simulate browser behaviors by sending HEAD or GET requests to probe the availability of backend servers. HTTPS supports encryption and provides higher security than HTTP.
• TCP: TCP health checks send TCP SYN packets to a backend server to probe the availability of backend servers.
• gRPC: gRPC health checks send POST or GET requests to a backend server to check whether the backend server is healthy.

The timeout period of a health check response. If a backend ECS instance does not respond within the specified timeout period, the ECS instance fails the health check. Unit: seconds.

Valid values: 1 to 300.

The number of times that an unhealthy backend server must consecutively pass health checks before it can be declared healthy. In this case, the health check status of the backend server changes from fail to success.

Valid values: 2 to 10.

The number of times that a healthy backend server must consecutively fail health checks before it can be declared unhealthy. In this case, the health check status of the backend server changes from success to fail.

Valid values: 2 to 10.

The cookie to be configured on the server.

The cookie must be 1 to 200 characters in length and can contain only ASCII characters and digits. It cannot contain commas (,), semicolons (;), or space characters. It cannot start with a dollar sign ($).

The timeout period of a cookie. Unit: seconds.

Valid values: 1 to 86400.

Specifies whether to enable session persistence. Valid values:

• true
• false (default)

The method that is used to handle a cookie. Valid values:

• Insert: inserts a cookie.

ALB inserts a cookie (SERVERID) into the first HTTP or HTTPS response packet that is sent to a client. The next request from the client contains this cookie and the listener forwards this request to the recorded backend server.

• Server: rewrites a cookie.

When ALB detects a user-defined cookie, it overwrites the original cookie with the user-defined cookie. Subsequent requests to ALB carry this user-defined cookie, and ALB determines the destination servers of the requests based on the cookies.

The type of the parameter. Only query strings are supported.

The value of the parameter used for consistent hashing.

Specifies whether to enable connection draining. Valid values:

• true
• false

The timeout period of connection draining.

Valid values: 0 to 900.

Indicates whether slow starts are enabled. Valid values:

• true
• false

The duration of a slow start.