Home/ Questions/Q 2868
Next
In Process

askthedev.com Latest Questions

Asked: 2024-09-24T11:11:13+05:30 In:

What are the steps to create an SSH key on an Ubuntu server or on my personal computer?

So, I’ve been trying to set up SSH keys on my Ubuntu server, and honestly, I’m feeling a bit lost. I’ve read a few tutorials online, but they all seem to be written for someone who’s already a pro at this, and I’m definitely not there yet. My goal is to connect to my server without having to type in my password every single time, and I’ve been told that creating an SSH key is the way to go.

But here’s the kicker: I’m not even sure where to start! Do I do this on my personal computer or directly on the server? Do I need to install anything special? I’ve got a basic understanding of the command line, so I hope I won’t get too far in over my head.

I’ve seen some people mention using the `ssh-keygen` command. Is that the way to go? What about permissions? I’ve heard that if you mess up your file permissions, it can lead to all sorts of security issues. That sounds pretty intimidating. Also, should I generate the key with or without a passphrase? I’ve seen both options presented, and I’m confused about the pros and cons. Would it even make a difference in my day-to-day use?

Once I generate the key, how do I actually get it to the server? I think I’ve heard of something called `ssh-copy-id`, but does that work for all types of servers? Is there a manual process I should know about in case that command doesn’t work?

And once I do manage to get it all set up, how can I test that it’s working correctly? I really want to avoid the headache of troubleshooting if things go wrong.

Any pointers or step-by-step advice would be super helpful. I’d love to hear about others’ experiences too—like how you managed to get through this process. Thanks in advance for any help you can give me!

Share

    Leave an answer

    You must login to add an answer.

    Need An Account,

    2 Answers



    1. Setting Up SSH Keys on Ubuntu


      Setting Up SSH Keys on Ubuntu

      Setting up SSH keys can seem a bit overwhelming at first, but once you get the hang of it, it’s pretty straightforward! Here’s a step-by-step guide to help you through the process.

      1. Generate SSH Key Pair

      First, you’ll want to create your SSH key. You do this on your personal computer, not the server. Open up your terminal and run the following command:

      ssh-keygen -t rsa -b 4096

      When prompted, you can press Enter to accept the default file location (usually ~/.ssh/id_rsa). It’s up to you if you want to enter a passphrase. A passphrase adds an extra layer of security, but it means you’ll have to enter it each time you use the key. If you want hassle-free connections, you can skip the passphrase by just pressing Enter.

      2. Check Permissions

      File permissions are indeed important! After generating your key, you should set the permissions of the .ssh directory and the key files like this:

      chmod 700 ~/.ssh
chmod 600 ~/.ssh/id_rsa
chmod 644 ~/.ssh/id_rsa.pub

      These commands ensure that only you can access your private key.

      3. Copying the Public Key to Your Server

      Next, you’ll need to send your public key to your server. You can use ssh-copy-id to do this easily:

      ssh-copy-id username@your_server_ip

      This command will prompt you for your server password—and once you enter it, your public key will be copied over. If this for some reason doesn’t work, you can manually copy your public key (~/.ssh/id_rsa.pub) and paste it into the ~/.ssh/authorized_keys file on your server.

      4. Testing the SSH Connection

      After copying the key, it’s time to test it! Simply try connecting to your server again:

      ssh username@your_server_ip

      If everything is set up correctly, you should connect without being prompted for a password. If it doesn’t work, double-check your steps—especially the permissions and whether you copied the key correctly.

      Common Pitfalls

      • Make sure the SSH service is running on your server.
      • Check that you’re using the correct username and server IP.
      • In case of error messages, examining your SSH configuration in /etc/ssh/sshd_config on the server might reveal issues.

      Building experience through hands-on practice is valuable, so don’t hesitate to experiment. You got this!


    2. To set up SSH keys for your Ubuntu server, you’ll want to start on your personal computer. This is where you’ll generate the SSH key pair using the `ssh-keygen` command. Open your terminal and input `ssh-keygen -t rsa -b 4096 -C “your_email@example.com”`. This command creates a new SSH key using the RSA algorithm with a key size of 4096 bits. You can choose to add a passphrase for additional security; this means you’ll need to enter the passphrase each time you use the key, but it protects your key in case it gets compromised. If you’re looking for convenience over added security, you can create it without a passphrase, but this makes your key less secure. After generating the keys, locate the public key (typically in `~/.ssh/id_rsa.pub`). For most installations, you don’t need to install anything special; SSH is usually included by default on Ubuntu systems.

      Next, you need to transfer the public key to your server. The easiest way to do this is by using the `ssh-copy-id` command, like so: `ssh-copy-id username@your_server_ip`. This command will prompt you for your password, then install your public key in the appropriate directory on the server. It’s compatible with most Linux servers, including Ubuntu. If for any reason `ssh-copy-id` doesn’t work, you can manually add your public key to the `~/.ssh/authorized_keys` file on your server. Just connect to your server with SSH and use a text editor to append the contents of `id_rsa.pub` to this file. Ensure the right permissions: the `.ssh` directory should have 700 permissions and the `authorized_keys` file should be 600. Finally, to test that everything works correctly, attempt to SSH into your server again: `ssh username@your_server_ip`. If it doesn’t prompt you for a password, congratulations, you’ve successfully set up SSH key authentication!

    Related Questions