SSH Without Prompting for Password

Configure SSH to avoid prompting for a password each time.

Problem Statement

Currently, after setting up SSH with a PEM file, you can access a server without a password like so:

ssh -i "ohio.pem" ubuntu@ec2-X.x.X.X.us-east-2.compute.amazonaws.com

However, when a user is created on the remote server with a password (e.g., user devops), SSH prompts for a password every time you log in:

ssh devops@3.19.xx.xx
EnterPassword:

We need to configure the local machine to stop asking for the password each time without changing anything on the remote server.

Configuration Steps

1. Edit SSH Config File

Create or edit the SSH configuration file located at ~/.ssh/config:

nano ~/.ssh/config

Add the following configuration:

Host 3.19.xx.xx
    HostName 3.19.xx.xx
    User ubuntu
    PreferredAuthentications password
    IdentityFile none

2. Identify Your Shell

Check your current shell with:

echo $SHELL

Depending on the shell, configuration files differ:

Bash: ~/.bashrc
Zsh: ~/.zshrc
Fish: ~/.config/fish/config.fish

3. Configure Shell Alias

Since the shell in use is Zsh, configure the .zshrc file:

nano ~/.zshrc

Add the following alias at the end of the file:

# ssc command alias
alias ssc='sshpass -p123 ssh'

Note: Replace 123 with the actual password of user devops.

4. Reload Shell Configuration

Reload the shell configuration:

source ~/.zshrc

5. Test SSH Connection

Test the SSH connection with the alias:

ssc 3.19.xx.xx   # First time, it asks for the password.

Exit and log in again:

ssc 3.19.xx.xx   # This time, login without prompt.

Additional Notes

known_hosts: Located at ~/.ssh/known_hosts, this file contains public keys of remote servers used to verify their identity during connections.
Config File: The SSH configuration file (~/.ssh/config) allows customization of connection settings for various hosts.

By following these steps, you can ensure that SSH connections do not prompt for passwords repeatedly while maintaining existing remote server configurations.

ravikyada/sshpass.md