• Jul 17, 2017 To ssh using pem file there are few steps you have to follow 1.Generating Key Pairs. To generate an RSA key pair for version 2 of the SSH protocol, follow these steps: Generate an RSA key pair by typing the following at a shell prompt: $ ssh-keygen or $ ssh-keygen -t rsa -b 2048 -v.
• Red Hat Enterprise Linux 6 uses SSH Protocol 2 and RSA keys by default (see Section 14.1.3. Do not generate key pairs as root, as only root would be able to use those keys. Before reinstalling your system, back up the /.ssh/ directory to keep the generated key pair. Copy the backed-up data to the home directory in the new system for.

• Generate Ssh Key Pair On Linux Computer
• Generate Public Private Key Pair
• How To Generate Ssh Key Pair In Linux
• Generate Ssh Key Pair On Linux Download
• Generate Ssh Key Pair On Linux Download
• Generate Ssh Key Pair On Linux Windows 7

Updated by LinodeWritten by Linode

Apr 02, 2019  Installation of SSH Keys on Linux - A Step-By-Step Guide Step One: Creation of the RSA Key Pair. Step Two: Copying the Public Key.

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Password authentication is the default method most SSH (Secure Shell) clients use to authenticate with remote servers, but it suffers from potential security vulnerabilities, like brute-force login attempts. An alternative to password authentication is public key authentication, in which you generate and store on your computer a pair of cryptographic keys and then configure your server to recognize and accept your keys. Using key-based authentication offers a range of benefits:

• Key-based login is not a major target for brute-force hacking attacks.

• If a server that uses SSH keys is compromised by a hacker, no authorization credentials are at risk of being exposed.

• Because a password isn’t required at login, you are able to able to log in to servers from within scripts or automation tools that you need to run unattended. For example, you can set up periodic updates for your servers with a configuration management tool like Ansible, and you can run those updates without having to be physically present.

This guide will explain how the SSH key login scheme works, how to generate an SSH key, and how to use those keys with your Linode.

How SSH Keys Work

SSH keys are generated in pairs and stored in plain-text files. The key pair (or keypair) consists of two parts:

• A private key, usually named id_rsa. The private key is stored on your local computer and should be kept secure, with permissions set so that no other users on your computer can read the file.

  Caution

• A public key, usually named id_rsa.pub. The public key is placed on the server you intend to log in to. You can freely share your public key with others. If someone else adds your public key to their server, you will be able to log in to that server.

When a site or service asks for your SSH key, they are referring to your SSH public key (id_rsa.pub). For instance, services like GitHub and Gitlab allow you to place your SSH public key on their servers to streamline the process of pushing code changes to remote repositories.

The authorized_keys File

In order for your Linode to recognize and accept your key pair, you will need to upload your public key to your server. More specifically, you will need to upload your public key to the home directory of the user you would like to log in as. If you would like to log in to more than one user on the server using your key pair, you will need to add your public key to each of those users.

To set up SSH key authentication for one of your server’s users, add your public key to a new line inside the user’s authorized_keys file. This file is stored inside a directory named .ssh/ under the user’s home folder. A user’s authorized_keys file can store more than one public key, and each public key is listed on its own line. If your file contains more than one public key, then the owner of each key listed will be able to log in as that user.

Granting Someone Else Access to your Server

To give someone else access to your server’s user, simply add their public key on a new line in your authorized_keys file, just as you would add your own. To revoke access for that person, remove that same line and save the changes.

Challenge-Response

When logging in to a server using SSH, if there is a public key on file on that server, the server will create a challenge. This challenge will be crafted in such a way that only the holder of the private SSH key will be able to decipher it.

This challenge-response action happens without any user interaction. If the person attempting to log in has the corresponding private key, then they will be safely logged in. If not, the login will either fail or fall back to a password-based authentication scheme.

SSH Key Passphrases

You can optionally provide an additional level of security for your SSH keys by encrypting them with a passphrase at the time of creation. When you attempt to log in using an encrypted SSH key, you will be prompted to enter its passphrase. This is not to be confused with a password, as this passphrase only decrypts the key file locally and is not transferred over the Internet as a password might be.

If you’d like to set up your logins so that they require no user input, then creating a passphrase might not be desirable, but it is strongly recommended nevertheless.

Linux and macOS

Generate a Key Pair

Perform the steps in this section on your local machine.

1. Create a new key pair.

   Caution

   This command will overwrite an existing RSA key pair, potentially locking you out of other systems.

   If you’ve already created a key pair, skip this step. To check for existing keys, run ls ~/.ssh/id_rsa*.

   If you accidentally lock yourself out of the SSH service on your Linode, you can still use the Lish console to login to your server. After you’ve logged in via Lish, update your authorized_keys file to use your new public key. This should re-establish normal SSH access.

   The -b flag instructs ssh-keygen to increase the number of bits used to generate the key pair, and is suggested for additional security.

2. Press Enter to use the default names id_rsa and id_rsa.pub in the /home/your_username/.ssh directory before entering your passphrase.

3. While creating the key pair, you will be given the option to encrypt the private key with a passphrase. This means that the key pair cannot be used without entering the passphrase (unless you save that passphrase to your local machine’s keychain manager). We suggest that you use the key pair with a passphrase, but you can leave this field blank if you don’t want to use one.

Upload your Public Key

There are a few different ways to upload your public key to your Linode from Linux and macOS client systems:

Using ssh-copy-id

ssh-copy-id is a utility available on some operating systems that can copy a SSH public key to a remote server over SSH.

1. To use ssh-copy-id, pass your username and the IP address of the server you would like to access:

2. You’ll see output like the following, and a prompt to enter your user’s password:

3. Verify that you can log in to the server with your key.

Using Secure Copy (scp)

Secure Copy (scp) is a tool that copies files from a local computer to a remote server over SSH:

1. Connect to your server via SSH with the user you would like to add your key to:

2. /entity-framework-auto-generate-key.html. Create the ~/.ssh directory and authorized_keys file if they don’t already exist:

3. Give the ~/.ssh directory and authorized_keys files appropriate file permissions:

4. In another terminal on your local machine, use scp to copy the contents of your SSH public key (id_rsa.pub) into the authorized_keys file on your server. Substitute in your own username and your server’s IP address:

5. Verify that you can log in to the server with your key.

Manually Copy an SSH Key

You can also manually add an SSH key to a server:

1. Begin by copying the contents of your public SSH key on your local computer. You can use the following command to output the contents of the file:

   You should see output similar to the following:

   Note that the public key begins with ssh-rsa and ends with [email protected].

2. Once you have copied that text, connect to your server via SSH with the user you would like to add your key to:

3. Create the ~/.ssh directory and authorized_keys file if they don’t already exist:

4. Give the ~/.ssh directory and authorized_keys files appropriate file permissions:

5. Open the authorized_keys file with the text editor of your choice (nano, for example). Then, paste the contents of your public key that you copied in step one on a new line at the end of the file.

6. Save and close the file.

   Note

   If you initially logged into the server as root but edited the authorized_keys file of another user, then the .ssh/ folder and authorized_keys file of that user may be owned by root. Set that other user as the files’ owner:

7. Verify that you can log in to the server with your key.

Connect to the Remote Server

1. SSH into the server from your local machine:

2. If you chose to use a passphrase when creating your SSH key, you will be prompted to enter it when you attempt to log in. Depending on your desktop environment, a window may appear:

   Caution

   Do not allow the local machine to remember the passphrase in its keychain unless you are on a private computer which you trust.

   You may also see the passphrase prompt at your command line:

3. Enter your password. You should see the connection establish in the local terminal.

Windows

The following instructions use the PuTTY software to connect over SSH, but other options are available on Windows too.

Generate a Key Pair with PuTTY

1. Download PuTTYgen (puttygen.exe) and PuTTY (putty.exe) from the official site.

2. Launch puttygen.exe. The RSA key type at the bottom of the window is selected by default for an RSA key pair but ED25519 (EdDSA using Curve25519) is a comparable option if your remote machine’s SSH server supports DSA signatures. Do not use the SSH-1(RSA) key type unless you know what you’re doing.

3. Increase the RSA key size from 2048 bits 4096 and click Generate:

4. PuTTY uses the random input from your mouse to generate a unique key. Microsoft 2019 32 bit key generator torrent. Once key generation begins, keep moving your mouse until the progress bar is filled:

5. When finished, PuTTY will display the new public key. Right-click on it and select Select All, then copy the public key into a Notepad file.

6. Save the public key as a .txt file or some other plaintext format. This is important–a rich text format such as .rtf or .doc can add extra formatting characters and then your private key won’t work:

7. Enter a passphrase for the private key in the Key passphrase and Confirm passphrase text fields. Important: Make a note of your passphrase, you’ll need it later:

8. Click Save private key. Choose a file name and location in Explorer while keeping the ppk file extension. If you plan to create multiple key pairs for different servers, be sure to give them different names so that you don’t overwrite old keys with new:

Manually Copy the SSH Key with PuTTY

1. Launch putty.exe. Find the Connection tree in the Category window, expand SSH and select Auth. Click Browse and navigate to the private key you created above: Virtual dj free download now.

2. Scroll back to the top of the Category window and click Session. Enter the hostname or IP address of your Linode. PuTTY’s default TCP port is 22, the IANA assigned port for for SSH traffic. Change it if your server is listening on a different port. Name the session in the Saved Sessions text bar and click Save:

3. Click the Open button to establish a connection. You will be prompted to enter a login name and password for the remote server.

4. Once you’re logged in to the remote server, configure it to authenticate with your SSH key pair instead of a user’s password. Create an .ssh directory in your home directory on your Linode, create a blank authorized_keys file inside, and set their access permissions:

5. Open the authorized_keys file with the text editor of your choice (nano, for example). Then, paste the contents of your public key that you copied in step one on a new line at the end of the file.

6. Save, close the file, and exit PuTTY.

7. Verify that you can log in to the server with your key.

Using WinSCP

Uploading a public key from Windows can also be done using WinSCP:

1. In the login window, enter your Linode’s public IP address as the hostname, the user you would like to add your key to, and your user’s password. Click Login to connect.

2. Once connected, WinSCP will show two file tree sections. The left shows files on your local computer and the right shows files on your Linode. Using the file explorer on the left, navigate to the file where you saved your public key in Windows. Select the public key file and click Upload in the toolbar above.

3. You’ll be prompted to enter a path on your Linode where you want to upload the file. Upload the file to /home/your_username/.ssh/authorized_keys.

4. Verify that you can log in to the server with your key.

Connect to the Remote Server with PuTTY

Start PuTTY and Load your saved session. You’ll be prompted to enter your server user’s login name as before. However, this time you will be prompted for your private SSH key’s passphrase rather than the password for your server’s user. Enter the passphrase and press Enter.

Troubleshooting

If your SSH connections are not working as expected, or if you have locked yourself out of your system, review the Troubleshooting SSH guide for troubleshooting help.

Upload your SSH Key to the Cloud Manager

It is possible to provision each new Linode you create with an SSH public key automatically through the Cloud Manager.

1. Log in to the Cloud Manager.

2. Click on your username at the top right hand side of the page. Then click on My Profile in the dropdown menu that appears:

   Note

   If you are viewing the Cloud Manager in a smaller browser window or on a smaller device, then the My Profile link will appear in the sidebar links. To view the sidebar links, click on the disclosure button to the left of the blue Create button at the top of the page.

3. From the My Profile page, select the SSH Keys tab, and then click Add a SSH Key:

4. Create a label for your key, then paste in the contents of your public SSH key (id_rsa.pub):

5. Click Add Key.

6. When you next create a Linode you’ll be given the opportunity to include your SSH key in the Linode’s creation. This key will be added to the root user of the new Linode.

   In the Create Linode form, select the SSH key you’d like to include. This field will appear below the Root Password field:

Next Steps

After you set up your SSH keys and confirm they are working as expected, review the How to Secure Your Server guide for instructions on disabling password authentication for your server.

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Related

Introduction

You have seen in previous tutorials how to use PuTTY to connect to your VPS securely and how to create SSH keys with PuTTYgen.

You might have more than one SSH key for a single cloud server, or simply more than one cloud server or Droplet that requires SSH keys to log into. This can make you feel overwhelmed with having to manage, sort out, and link all those keys to their respective servers. That’s why Pageant exists.

Pageant is a PuTTY authentication agent. It holds your private keys in memory so that you can use them whenever you are connecting to a server. It eliminates the need to:

• Explicitly specify the relevant key to each Linux user account, if you use more than one account to log into a server
• Type a key’s passphrase each time you log into your user account; and your keys should be passphrase protected since having an unprotected key is as good as hiding your password under your keyboard!

Prerequisites

Make sure you have these prerequisites.

• Pageant is installed together with the PuTTY suite; if you don’t have it installed, you can download it here
• You should already have at least one SSH key saved on your local computer

Step 1 — Adding Keys to Pageant

Start Pageant from the PuTTY folder: Start-Menu > All Programs > PuTTY > Pageant

Pageant starts by default minimized in the system tray. To begin adding your SSH keys, you should right click on its icon and then the following context menu will show up:

Clicking on Add Key from the menu or View Keys to open up the Pageant Key List window. Here you can view, add, and remove keys:

Generate Ssh Key Pair On Linux Computer

Tip: You can access the Pageant Key List window directly by double-clicking its icon in the system tray.

Click the Add Key button. This will open the file explorer, where you can choose one or more keys at a time to load. You should select files with the .ppk extension:

Click the Open button to load the keys with Pageant.

If a key is passphrase-protected, you will be prompted to enter the passphrase only once before it can be added to the Pageant Key List:

After successfully adding a key, you can now see it listed:

Step 2 — Connecting to the Server(s)

Now these keys will be available while connecting to any server during your PuTTY sessions. You don’t have to take any extra steps in PuTTY. Just enter your hostname or IP address, and SSH user. PuTTY will automatically try to authenticate using any keys currently loaded in Pageant.

Generate Public Private Key Pair

Step 3 (Optional) — Removing Keys from Pageant

If you want to remove a key from Pageant, select that key from the Pageant Key List window and press the Remove Key button. You can also remove multiple keys together by selecting them with CTRL or SHIFT.

Tips & Tricks

Use these tips to automate your authenticated connections with Pageant.

Loading Keys Automatically on Pageant Startup

You can make Pageant automatically load one or more private keys when it starts up, instead of adding them manually every time you start up Pageant.

Go to the Pageant shortcut icon from the Windows Start Menu or your desktop.

Right click on the icon, and click on Properties.

A new window will open containing the shortcut’s properties:

From the Shortcut tab, edit the Target field. Leave the path to pageant.exe intact. After that path, add paths to your .ppk key files. These should be outside the quotation marks. Here’s an example:

Click the Apply and then OK buttons.

How To Generate Ssh Key Pair In Linux

Note: If the keys are encrypted, Pageant will request the passphrases on startup.

Making Pageant Run PuTTY

You can make Pageant start PuTTY or any other program once it has initialized itself and loaded any keys specified on its command line. That way you can just start Pageant instead of having to start both programs.

Generate Ssh Key Pair On Linux Download

You can achieve this by following the same steps we used previously to add the keys automatically (see the previous section). Just add the program’s path at the end of the command in the Target field, preceded by the -c option, and contained within double quotes. Here’s an example of the full line for the Target field:

Generate Ssh Key Pair On Linux Download

Other PuTTY Suite Products

Here are a few other helpful applications that can work with PuTTY.

Generate Ssh Key Pair On Linux Windows 7

• PuTTYgen: A tool to generate and edit SSH public and private key pairs. It is part of the PuTTY suite, but it can also operate with the private key formats used by some other SSH clients like WinSCP
• PSFTP: An interactive text-based client for the SSH-based SFTP (secure file transfer) protocol, that allows you to run an interactive file transfer session and perform many thing like listing the contents of directories, browsing around the file system, issuing multiple get and put commands, etc.
• PSCP (PuTTY Secure Copy Client): A tool for transferring files securely between computers using an SSH connection