Linux SSH Cheat Sheet

Secure shell commands for remote access and file transfer.

What this cheat sheet is for

This linux ssh reference helps you complete common developer tasks quickly and avoid repeated trial-and-error when working under deadlines.

When you need a reliable command or pattern during debugging and incident response.
When you are implementing a feature and want a known-good syntax example immediately.
When onboarding teammates and documenting repeatable workflows for daily use.
When reviewing pull requests and verifying that command usage follows best practices.

Connect to remote host.

ssh user@hostname
ssh -p 2222 user@hostname
ssh -i ~/.ssh/key.pem user@hostname
ssh user@hostname command

Create SSH key pair.

ssh-keygen
ssh-keygen -t rsa -b 4096
ssh-keygen -t ed25519
ssh-keygen -t rsa -C "email@example.com"

Copy key to remote server.

ssh-copy-id user@hostname
ssh-copy-id -i ~/.ssh/id_rsa.pub user@hostname

Copy files securely.

scp file.txt user@host:/path/
scp user@host:/path/file.txt ./
scp -r directory/ user@host:/path/
scp -P 2222 file.txt user@host:/path/

Create ~/.ssh/config file.

Host myserver
    HostName 192.168.1.100
    User username
    Port 22
    IdentityFile ~/.ssh/key.pem

# Connect using:
ssh myserver

Forward ports through SSH.

ssh -L 8080:localhost:80 user@host
ssh -R 8080:localhost:80 user@host
ssh -D 1080 user@host

Manage SSH keys.

eval $(ssh-agent)
ssh-add ~/.ssh/id_rsa
ssh-add -l
ssh-add -D

People often copy a command or pattern without adapting placeholders, which can break production workflows unexpectedly.
It is easy to forget environment-specific differences, so always verify behavior in your shell, runtime, or API gateway before shipping.
Many errors come from skipping small validation steps, so test with realistic sample input before relying on the result.

Last updated: February 2026