SSH connection basics in Linux CLI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does SSH stand for and what is its main purpose?

SSH stands for Secure Shell. It is used to securely connect to a remote computer over a network, allowing you to control it as if you were sitting in front of it.

beginner

What is the basic command syntax to connect to a remote server using SSH?

The basic command is ssh username@hostname. Here, username is your user on the remote machine, and hostname is the server's address or IP.

beginner

Why is SSH considered secure compared to older methods like Telnet?

SSH encrypts all data sent between your computer and the remote server, protecting passwords and commands from being seen by others on the network.

intermediate

What is the purpose of SSH keys in connection?

SSH keys are pairs of cryptographic keys used to authenticate without typing a password. The private key stays on your computer, and the public key is placed on the server.

beginner

How can you specify a different port number when connecting with SSH?

Use the -p option followed by the port number, like ssh -p 2222 username@hostname if the server uses a port other than the default 22.

What default port does SSH use to connect to a server?

A 22

B 80

C 443

D 21

SSH uses port 22 by default for secure connections.

Which command would you use to connect to user 'alice' on server 'example.com'?

A ssh example.com@alice

B ssh [e-mail]

C ssh connect alice example.com

D ssh -u alice example.com

The correct syntax is ssh username@hostname, so ssh [e-mail] is correct.

What does SSH encrypt during a connection?

A Nothing, it is not encrypted

B Only the commands

C Only the password

D All data including commands and passwords

SSH encrypts all data sent between client and server, including commands and passwords.

How do SSH keys improve security?

A By allowing anonymous login

B By making the connection faster

C By replacing passwords with cryptographic keys

D By disabling encryption

SSH keys replace passwords with cryptographic keys, making authentication more secure.

Which option lets you connect to a non-default SSH port?

A -p

B -d

C -P

D -port

The -p option specifies the port number for SSH connections.

Explain how you would connect to a remote server using SSH and what information you need.

Think about the command format and what identifies the remote machine and user.

Describe why SSH is a secure way to connect to remote computers compared to older methods.

Focus on what SSH protects during the connection.