Websocket passed the local test, but cannot be connected in the production environment.

Use swoole for websocket. The Development Environment passes the test. The test details are: {code ...} the Development Environment encountered a problem. The test details are: {code ...} second Attempt: backend: {code ...} front end: {code ...} third attempt: backend: {code ...} front end: {code... use swoole for websocket,
The Development Environment passes the test. The test details are as follows:

Backend: swoole 0.0.0.0 terminal 9503.html page: ws // 192.168.1.101: 9503 can be connected, and ws // 127.0.0.1: 9503 can be connected.

The test details are as follows:

Backend: IP address of the swoole listening server A. B .C.D, port 9503. an error occurred while enabling the process. The message [16:57:23 @ 9876.0] WARN swSocket_listen: bind (A. B .C.D: 9503) is displayed. error: Cannot assign requested address [99]

Second Attempt:
Backend:

Swoole listens to the server IP address 127.0.0.1 and port 9503. The process is successfully enabled.

Front end:

Ws // A. B .C.D: 9503 cannot be connected,

The third attempt:
Backend:

Swoole listens to the server IP address 0.0.0.0 and port 9503. The process is successfully enabled.

Front end:

Ws // A. B .C.D: 9503 cannot be connected,

There is no clue why the process is successfully enabled but cannot be connected. Help !!!

Reply content:

Use swoole for websocket,
The Development Environment passes the test. The test details are as follows:

Backend: swoole 0.0.0.0 terminal 9503.html page: ws // 192.168.1.101: 9503 can be connected, and ws // 127.0.0.1: 9503 can be connected.

The test details are as follows:

Backend: IP address of the swoole listening server A. B .C.D, port 9503. an error occurred while enabling the process. The message [16:57:23 @ 9876.0] WARN swSocket_listen: bind (A. B .C.D: 9503) is displayed. error: Cannot assign requested address [99]

Second Attempt:
Backend:

Swoole listens to the server IP address 127.0.0.1 and port 9503. The process is successfully enabled.

Front end:

Ws // A. B .C.D: 9503 cannot be connected,

The third attempt:
Backend:

Swoole listens to the server IP address 0.0.0.0 and port 9503. The process is successfully enabled.

Front end:

Ws // A. B .C.D: 9503 cannot be connected,

There is no clue why the process is successfully enabled but cannot be connected. Help !!!

Network Firewall Problems

The IP address is incorrect. swoole cannot listen to the specified address and port.