How to Add SSH Key to Authorized_keys
In the realm of secure remote access, SSH (Secure Shell) is an essential tool for system administrators and developers. One of the most crucial aspects of SSH is managing access to your servers and machines. One of the primary ways to do this is by adding your SSH key to the authorized_keys file. This article will guide you through the process of adding an SSH key to the authorized_keys file on a Linux server.
Understanding SSH Keys
SSH keys are a pair of cryptographic keys used to authenticate a user or a machine. They consist of a public key and a private key. The public key is stored on the server, while the private key is kept on the client machine. When you attempt to connect to a server using SSH, the server checks the authenticity of the client by verifying the signature of the public key with the private key.
Generating SSH Key Pair
Before adding your SSH key to the authorized_keys file, you need to generate an SSH key pair. You can do this using the ssh-keygen command. Open your terminal and run the following command:
“`
ssh-keygen -t rsa -b 4096
“`
This command will generate an RSA key pair with a key length of 4096 bits. You will be prompted to enter a file path for the private key. You can leave this blank to use the default path. Next, you will be asked to enter a passphrase for your key. This passphrase will protect your private key, so it is recommended to use a strong passphrase.
Adding SSH Key to Authorized_keys
Once you have generated your SSH key pair, you need to add the public key to the authorized_keys file on the server. To do this, follow these steps:
1. Log in to your server using your existing user credentials.
2. Copy the contents of your public key by running the following command:
“`
cat ~/.ssh/id_rsa.pub
“`
3. Open the authorized_keys file in a text editor. You can use the nano, vi, or any other text editor you prefer. For example:
“`
nano ~/.ssh/authorized_keys
“`
4. Paste the contents of your public key into the authorized_keys file. Make sure to add a new line after the last entry.
5. Save and close the file.
Testing SSH Connection
Now that you have added your SSH key to the authorized_keys file, you can test the SSH connection by trying to connect to the server using the following command:
“`
ssh username@server_ip
“`
If everything is set up correctly, you should be able to log in without entering your password.
Conclusion
Adding an SSH key to the authorized_keys file is a crucial step in securing your remote access to a Linux server. By following the steps outlined in this article, you can easily add your SSH key to the authorized_keys file and enjoy the convenience of passwordless SSH connections. Remember to keep your private key secure and generate new key pairs periodically for enhanced security.
