abernal's blog

In order to check ports in linux, we can use the next tools

LSOF

​[abernal@sandbox ~]$ sudo dnf install lsof

Basic usage

1. To list the open ports and the process that owns them, execute the next command

In order to configure postfix as a SMTP mail server in fedora, please follow this process

Process

1. Execute the next command from the console to install postfix

[abernal@sandbox ~]$ sudo dnf install postfix

2. Execute the next command to install mailx

[abernal@sandbox ~]$ sudo dnf install mailx

3. Check that port 587 is not bloqued by a firewall (default firewall : iptables)

​[abernal@sandbox ~]$ sudo iptables -L | grep 587

​4. Open the postfix master.cf file