Showing posts with label TCP. Show all posts
Showing posts with label TCP. Show all posts

Saturday, January 21, 2023

Error binding socket to :::25, status = EADDRINUSE (Solved)

$ yum install net-tools 

$ sudo dnf install net-tools 

Debian, Ubuntu: 
$ sudo apt install net-tools

netstat -tulpn

netstat -tulpn | grep -w 2500

Result: tcp     0         0   *

kill 942

Wednesday, August 10, 2022

How to check TCP, UDP Domain Socket using NetCat

 Install the netcat Using the fllowing command:

$ yum install nc      [On CentOS/RHEL]

$ dnf install nc      [On Fedora 22+ and RHEL 8]

$ sudo apt-get install Netcat      [On Debian/Ubuntu]

NetCat commands:

$ nc -v -w 2 z 22     #scan a single port


$ nc -v -w 2 z 22 80  #scan multiple ports


$ nc -v -w 2 z 20-25  #scan range of ports

How to install SSL on CWP hostname?

1 - Check that you should have an A record for the hostname. For example if your server hostname is, then you should have a...