BGP (Border Gateway Protocol) is the routing protocol of the Internet, and because of the size of the global network, […]
Point-to-Point GRE VPN Tunnel on Cisco Devices
GRE VPN is not a good VPN Tunneling technology and this is just a reference guide for information because does […]
NAT type Port Address Translation (PAT) on Cisco Devices
There are 3 types of NAT: Static NAT – Translates a private to a public address (1-to-1). Dynamic NAT – […]
Setting Up a Headless Raspberry Pi + SSH + VNC + WiFi
The following steps will work in any Raspberry Pi with Raspbian (now called Raspberry Pi OS), regardless of the model. […]
Using SCP and RSYNC for Copying and Syncing
Both SCP and RSYNC, use SSH Protocol as a way to transfer files and directories. While SCP just uploads or […]
Working with ACLs on Cisco Devices
An ACL is a list of rules that can be applied to an interface to make a policy to the […]
VSFTPD + TLS + Fail2Ban on Ubuntu 20.04
Assuming you already have an SSL/TLS key that you may have created for your HTTP server [Read It], we will […]
Using MSMTP with Google SMTP Relay on Ubuntu 20.04
This SMTP application works the same way on Raspbian 10 (Buster). sudo apt-get install msmtp msmtp-mta -y sudo nano /etc/msmtprc […]
Changing Prompt Color on Bash Terminal
There is no technical reason to change the color of the terminal console, but anyone can issue commands as another […]
SPF + DKIM + DMARC Overview
Tools against SPAM and domain spoofing: SPF – Whitelist of hosts that are allowed to send email on behalf of […]