Most guides to bash history shortcuts exhaustively list all of the shortcuts available to you.
The problem I always had with that was that I would use them once, and then glaze over as I tried out all the possibilities. Then I’d move onto my working day and completely forget them, retaining only the well-known !! trick I learned when I first started using bash.
So most never got committed to memory.
Here I outline the shortcuts I actually use every day.
Source: Seven God-Like Bash History Shortcuts You Will Actually Use – zwischenzugs
Some Internet service providers and corporate companies might have blocked most of the ports, and allowed only a few specific ports such as port 80 and 443 to tighten their security. In such cases, we have no choice, but use a same port for multiple programs, say the HTTPS Port 443, which is rarely blocked. Here is where SSLH, a SSL/SSH multiplexer, comes in help. It will listen for incoming connections on a port 443. To put this more simply, SSLH allows us to run several programs/services on port 443 on a Linux system. So, you can use both SSL and SSH using a same port at the same time. If you ever been in a situation where most ports are blocked by the firewalls, you can use SSLH to access your remote server. This brief tutorial describes how to share a same port for https, ssh using SSLH in Unix-like operating systems.
Source: SSLH – Share A Same Port For HTTPS And SSH – OSTechNix
Related: Install sslh on Mac OSX
In this tutorial, we learn how to use curl command in linux. Expained with examples to download single and mutiple files from remote server.
Source: How to Use Curl Command with Examples (Linoxide)
By default, ssh server performs a reverse DNS lookup for authentication requests. This can be so annoying as you wait ten’s of seconds for the lookup to finish. You may experience a delay before receiving a password prompt while accessing a remote system via ssh.
This guide will show you how to disable SSH reverse DNS lookups in a Linux/Unix system. The method discussed here works for all Linux and Unix based operating systems running OpenSSH Server.
Source: How To Disable SSH reverse DNS Lookups in Linux/Unix system – Computing for Geeks