To verify if Nginx is listening on the desired ports, you can use the lsof command. Lsof, short for “list open files,” is a powerful utility that provides information about files opened by processes on a Unix-like system.
First, you need to open a terminal or command prompt and execute the following command:
“`
Lsof -i :80
“`
This command will display all the processes that are listening on port 80. If Nginx is running and successfully bound to port 80, you should see an output similar to:
“`
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
Nginx 12345 nginx 4u IPv4 12345 0t0 TCP *:80 (LISTEN)
“`
The “COMMAND” column shows the name of the process (in this case, “nginx”), and the “PID” column displays the process ID. The “FD” column specifies the file descriptor, and “TYPE” represents the type of file. In this example, “4u” indicates that it is an IPv4 TCP socket. The “DEVICE” column displays the device number, and “SIZE/OFF” shows the size or offset. The “NODE” column indicates the node ID, and “NAME” displays the address and port number being listened to.
If you don’t see any output or the output doesn’t include Nginx, it means that Nginx is not listening on port 80. Possible reasons could be that Nginx is not running, or it is bound to a different port. You can modify the command to check for other specific ports, such as port 443:
“`
Lsof -i :443
“`
The process information displayed should be similar to the previous example.
If you want to check for all open network connections and associated processes, you can use the following command:
“`
Lsof -i
“`
This command will display a list of all processes with open network connections, including the ones listening on ports 80 and 443 if Nginx is running.
By using the lsof command with the appropriate options, you can verify if Nginx is listening on the desired ports. If Nginx is running and successfully bound to the ports, you will see the corresponding process information in the output. Otherwise, there won’t be any output related to Nginx on the specified ports.