Beginner's Guide to First SSH Connections

Introducing a tutorial for programming beginners about secure shell SSH, which can be used in Linux PC/server command lines, Bash programming language (scripting language), as well as Windows and Mac.

Q. How do I SSH connect?

First, let’s grasp the basic terms.

• cmd(DOS;batch) … Shell language widely prevalent in Windows. Not used much, but it’s useful for some operations that require administrator privileges that PowerShell can’t perform
• powershell … Shell language widely prevalent in Windows. Recently open-sourced and demand is increasing, but it doesn’t match bash.
• bash … Shell language widely prevalent in Linux
• WSL bash … Windows Subsystem for Linux. A new feature implemented in recent Windows updates. The ultimate thing that allows you to use bash language on Windows.
• conemu … Software for handling shell language in Windows. Called terminal, command line, or console.
• xterm … Software for handling shell language in Linux. Called terminal, command line, or console.
• terminator … Software for handling shell language in Linux. Called terminal, command line, or console.
• Command … Operations in shell language. For example, mkdir which creates new folders. Commands can be increased extensively, but in the initial Linux stage, about 700 commands are available.
• ssh … Technology for accessing or operating remote computers - called host machines. On the other hand, the machine you’re operating is called a client machine. - On computers accessed via ssh, you can freely use bash language and commands.

This is conemu.

Let’s download conemu.

Download ConEmu latest release

Let’s install wsl.

WSL bash on ubuntu on windows installation procedure

Want to know more about wsl?

I’ve been using WSL (Windows Subsystem for Linux) since the beginning, so I’ll explain the benefits of WSL for Linux and programming beginners

This time, we’ll SSH connect using wsl bash on conemu.

The ssh command has the following format:

ssh -p [port] -i [identityFile] [username]@[host]

In my environment, it becomes:

ssh -p 10022 -i ~/.ssh/shit.key [email protected]

First, preparation.

Enable ssh on the server side.

Download the identity file.

Check the server’s host address.

I’ll explain the command.

-p [port] … Usually, port 22 is the ssh port. However, many server administrators change the port number for security reasons. Xserver is one of them, and 10022 is Xserver’s ssh port.

List of TCP and UDP port numbers - Wikipedia

-i [identityFile] … Enter the path of the downloaded identity file. It will be like /mnt/c/Users/user/Downloads/iden.key.

[username]@[host] … The first argument of the ssh command. Write the username and server name connected with @. The hostname can also be an IP address.

Once you can input the command, press enter.

Enter the password you set when creating the identity file.

Now you’ve SSH connected to the remote server.

Q. What’s an ssh client?

It’s a remnant of what people used in the past. You can use it if you want, but there’s no benefit. You can think of it as a limited version of console software like conemu. Or it might be used in environments where usable software is limited, such as in specific companies.

Q. What can ssh do?

ssh can do almost anything. It’s a very convenient technology, so please learn to use it.

• rsync … Can do differential backup of files between host and client. An enhanced version of the cp command. Very fast.
• sshfs … Can mount entire file systems.
• ssh -t … Tunneling. Can use multiple PCs as stepping stones for ssh connections. By editing the sshd_config file to allow access only from specific IPs, you can enhance security
• ssh -R 52698:localhost:52698 … Port forwarding from client to host
• ssh -L 4567:localhost:4567 … Port forwarding from host to client
• ssh -X … Can do x11 forwarding. Can open software on wsl bash or Linux on client Linux or Windows.