Using Putty To Generate Ssh Key
- Dec 18, 2019 In this tutorial, we will walk through how to generate SSH keys on Ubuntu 18.04 machines. We will also show you how to set up an SSH key-based authentication and connect to your remote Linux servers without entering a password.
- Sep 26, 2019 You can use PuTTY to generate SSH keys. PuTTY is a free open-source terminal emulator that functions much like the Terminal application in macOS in a Windows environment. This section shows you how to manually generate and upload an SSH key when working with PuTTY.
- May 04, 2015 Verified and Tested 2/8/15 Introduction. This guide will show you how to generate and use SSH keys (public and private) using PuTTYgen and PuTTY for Linux servers. How to Generate and Use an SSH Key.
- How To Configure SSH Keys Authentication With PuTTY And Linux Server In 5 Quick Steps. This tutorial explains how you can replace password-based SSH authentication with key-based authentication which is more secure because only the people that own the key can log in.
- May 08, 2019 PuTTY uses this format as well; so if you have generated an SSH-1 private key using OpenSSH or ssh.com’s client, you can use it with WinSCP, and vice versa. Hence, the export options are not available if you have generated an SSH-1 key.1. You can also use WinSCP /keygen command-line switch to convert the private key from other formats.
- PuTTYgen is a key generator tool for creating pairs of public and private SSH keys. It is one of the components of the open-source networking client PuTTY. Although originally written for Microsoft Windows operating system, it is now officially available for.
PuTTY does not natively support the private key format for SSH keys. PuTTY provides a tool named PuTTYgen, which converts keys to the required format for PuTTY. You must convert your private key (.pem file) into this format (.ppk file) as follows in order to connect to your instance using PuTTY.
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SSH keys are one of the most secure SSH authentication options. It is definitely more secure than the usual SSH password authentication. Therefore, it is highly recommended to use SSH Key authentication method for connections to your servers.
With password authentication, you can connect to your server from any location, you only need to fill in your password. However, if your password gets leaked, it is a major risk as anyone who knows your password will be able to get into the server.
SSH Key authentication only allows connections from clients whose key matches the one on the server. Basically, you generate a key pair (private key and public key). The private key is placed on your local machine and the public key is uploaded to the server. When connecting to the server, a validation of these two keys is made and if the key pair passes the validation you are allowed to connect. Of course, you can upload keys of multiple users so that you or other authorized users would be able to connect to the server from different computers.
As you can see this is a much safer connection method. In this tutorial, we will focus on Windows users who use PuTTY for connections to the server and show how to generate PuTTYSSH Keys. If you want to generate SSH Keys on Linux or Mac, see this tutorial.
What you’ll need
Before you begin this guide you’ll need the following:
- Access to your Linux server / VPS
- PuTTY and PuTTYgen installed on your computer (Download here)
Step 1 — Downloading PuTTYgen
Most of you have PuTTY installed on your computers already, however, to generate SSH Keys you also will need PuTTYgen.
- Download PuTTYgenhere
- You should be able to see this file downloaded:
No installation is required for PuTTYgen, it will run when you execute the file.
Step 2 — Generating your SSH Key pair
- Open up PuTTYgen by double clicking on the puttygen.exe file you have downloaded in Step 1.
- You should be able to see a window like this:
- Before generating your SSH Key pair, you can edit some settings, for example, key length, however, in most cases the default options will work just fine.
- Generate your SSH Key pair by clicking the Generate button.
- When the progress bar starts loading, move your mouse randomly across the area to load up the bar and generate your key pair.
- Your public SSH key will be displayed on the screen:
- For additional security it is highly recommended to think of a passphrase for your SSH key (However, you can also leave it empty):
- Save your private key to any desired location on your computer and name it anything you like.
- Save your public key to the same location on your computer and name it anything you like.
And that is it, you have generated your SSH Key pair. The private key will stay on your computer (do not provide it to anyone) while your public key needs to be uploaded to the server you wish to connect to.
Step 3 — Setting up your private key on PuTTY
In order for the server to recognize your computer when connecting from PuTTY, you need to attach the private key to PuTTY.
- Open up PuTTY.
- Navigate to Connection -> SSH -> Auth in the left sidebar.
- Browse for your private key file in the field Private key for authentication
- Select the private key file with .ppk ending and click Open.
Step 4 – Adding public key to server
Lastly, you need to upload your public key to the server:
- On your local computer, open public key file (id_rsa.pub) you generated in Step 2 with any text editor and copy its contents (public key).
- Connect to your VPS using Putty. See this guide for detailed steps.
- If .ssh folder does not exist, create it together with authorized_keys file with the following command:
mkdir ~/.ssh touch ~/.ssh/authorized_keys
- Secure SSH Key file by changing permissions:
chmod 0700 ~/.ssh; chmod 0644 ~/.ssh/authorized_keys
- Open authorized_keys file with vim text editor:
vim ~/.ssh/authorized_keys
- Press i key on your keyboard and right mouse button to paste the public key.
- Press Esc button and type in
:x
, hit Enter button. This command will save changes made to the file.
That is it, you can now use SSH keys instead of SSH password authentication to connect to your VPS.
Conclusion
You have learned how to generate PuTTY SSH Keys using PuTTYgen. This will make your connection to the server a lot more secure and convenient as you will not need to fill in the password each time. We recommend using this way of SSH authentication at all times and disable password authentication for good to completely secure your server. To find out how to completely disable SSH Password authentication on your server and use SSH Key authentication instead, follow this tutorial: How to disable SSH Password authentication on VPS.
PuTTYgen is a key generator tool for creating pairs of public and private SSH keys. It is one of the components of the open-source networking client PuTTY. Although originally written for Microsoft Windows operating system, it is now officially available for multiple operating systems including macOS, Linux. PuTTYgen.exe is the graphical tool on Windows OS. While on the other side, Linux OS has the only command-line version could be accessible using SSH commands.
- 1 Download PuTTYgen
- 1.1 Download PuTTYgen on Windows
- 1.2 Download PuTTYgen for Mac
- 1.3 Download PuTTYgen for Ubuntu/Linux
- 1.3.3 Types of Keys Supported on PuTTYgen
Puttygen aka Putty Key Generator
The key generation utility – PuTTYgen can create various public-key cryptosystems including Rivest–Shamir–Adleman (RSA), Digital Signature Algorithm (DSA), Elliptic Curve Digital Signature Algorithm (ECDSA), and Edwards-curve Digital Signature Algorithm (EdDSA) keys.
The aforementioned public-key cryptosystems principally focus on secure data transmission and digital signatures.
Although PuTTYgen collects keys in its native file format i.e. .ppk files, the keys can easily be converted to any file format. For Windows, the software interface is PuTTYgen.exe, whereas, for Linux OS the command-line adaptation is available using SSH commands.
How to use PuTTYgen?
PuTTYgen is used to generate public or private key pair for creating SSH keys. Below is the complete guidance about how to generate RSA key in the Windows operating system:
- Once you install the PuTTY on your machine, you can easily run PuTTYgen. For the same, go to Windows -> Start Menu -> All Programs -> PuTTY -> PuTTYgen.
- You will see the PuTTY key generator dialog box on your screen
- You will find a “Generate” button in that dialog. Clicking on it will lead to generating the keys for you.
- Now you will need to add a unique key passphrase in the Key passphrase and Confirm passphrase field.
- Click on the “Save Public Key” and “Save Private Key” buttons to save your public and private keys.
- You will see the text starting with ssh-RSA in the Public key for pasting into OpenSSH authorized_keys file field which is located at the top of the window. Copy that entire text to your clipboard by pressing ctrl+c as you will require the key to paste on your clipboard in the public key tool of control panel or directly on the cloud server.
Various Ways to Use RSA Key Pair
RSA key pair generated through PuTTYgen is used in two various ways defined as below:
- To assign while creating a new cloud server
You can choose the public key from the given list of keys at the time of creating a cloud server. If you don’t find your key in that list, then first add and then assign it. - Assign to an existing cloud server
At the time of connecting to the cloud server, first of all, you need to tell PuTTY to use it for utilizing your newly created RSA key pair.
PuTTYgen being a component of the terminal emulator PuTTY does not have to be downloaded separately, hence, comes with the PuTTY .msi installation package. You can follow the simple steps to download PuTTYgen software for your system. That is the reason why you don’t need to download PuTTYgen separately. Once you download PuTTY software, you will be able to install and run PuTTYgen easily in no time. Below is the complete instruction about how to download and install PuTTY on Windows.
Apart from that, it is also integrated into third-party programs such as WinSCP installation package. Below you can find a complete PuTTYgen download and installation guide for all operating systems.
Download PuTTYgen on Windows
To download PuTTYgen the primary requisite is to acquire the copy of PuTTY installation package. For the 64-bit operating system, one must install the 64-bit version of PuTTY, i.e. putty-64bit-<version>-installer.msi.Similarly, for the 32-bit operating system, the respective 32-bit version of PuTTY, i.e. putty-<version>-installer.msi needs to be installed.
To get PuTTY, go to PuTTY Installation Download page, whereby the complete installation package will be available with setup instructions, installation guide, and download links to all other components of PuTTY such as putty.exe, pscp.exe, psftp.exe, puttytel.exe, plink.exe, pageant.exe and putty.zip.
Following the successful download of the PuTTY installation package. It is time to install the program. Go to How to install PuTTY on Windows, whereby you will find the step by step guidance for PuTTY installation for Windows operating system.
After successfully downloading and installing PuTTY on your Windows machine, you are just 2-3 clicks away to run PuTTYgen. Follow the below-given step by step guidance to run PuTTYgen:
Generate Ssh Key Github
Run PuTTYgen on Windows
Putty Ssh Using Key
To run PuTTYgen, Go to Windows -> Start Menu -> All Programs -> PuTTY -> PuTTYgen. You will see a window for the PuTTY Key Generator on your screen.
Voila! Now you can generate public or private key pair using PuTTYgen.
Download PuTTYgen for Mac
Below is the detailed guide to download PuTTYgen on Mac operating system. Mac OS has a built-in command-line SSH client known as Terminal. To utilize it, go to Finder and then opt for Go -> utilities from the top menu. After that find the terminal which supports SSH connections to remote servers.
However, to run PuTTYgen for mac, the first one must have to install PuTTY. There are multiple ways to install PuTTY, which are Homebrew or MacPorts. Both alternatives will also install the command-line of adaptations of PuTTYgen.
Ported PuTTY for Mac
Mac has the port of PuTTY which can be installed in various ways described as below:
- Installation using Homebrew:
First, install the ‘brew command line’ Once installed use the below-given command to install PuTTY:-sudo brew install putty
- Installation using MacPorts:
First of all, one must install MacPorts and then use the command-line to install PuTTY. Here is the command to install PuTTY via MacPortssudo port install putty
Additionally, a user can also add a shortcut to the desktop by writing the following command line–cp /opt/local/bin/putty ~/Desktop/PuTTY
However, there is an alternative way to install PuTTY on Mac OS. Cyberduck is a widely used Mac OS SSH Client. Once PuTTY installed on the Mac OS, a user can convert PuTTY derived private key format to OpenSSH.
To convert the private key to standard PEM format, type the following command –
puttygen privatekey.ppk -O private-openssh -o privatekey.pem
Using Putty To Generate Ssh Key
You can also read the guide to convert .pem file to .ppk using puttygen.
Download PuTTYgen for Ubuntu/Linux
To download PuTTYgen for Ubuntu (Linux) operating system, a user to first install PuTTY. However, in some Linux distributions, the SSH key generation tool – PuTTYgen needs to be installed independently from the PuTTY client.
For example, Debian Linux requires the below-given code to install PuTTYgen:
sudo apt install putty-tools
Bubble trouble 1 download mac.
Generate Key Pair for Authentication in Linux
To create the key pair for authentication in Linux use the below command:-
puttygen -t rsa -b 2048 -C 'user@host' -o keyfile.ppk
Various Command Line Options of PuTTY in Linux
Below are few important command line options in the Linux operating system for PuTTY:
PuTTYgen [-t keytype [-b bits] [-q] keyfile]
[-C new-comment] [-P]
[-O output-type -p -l -L]
[-o output-file]
Options:
- Keyfile – It is the name of the existing key file to read at the time of changing the current key.
- –t keytype – The command specifies the type of key to creating. Its acceptable values are RSA and dsa.rsa1.
- -b bits – This command specifies a total number of bit in a particular key. 1024 is the perfect size for DSA key, while 2048 or 4096 are the perfect size for RSA keys.
- –q – The command suppresses the message about progress at the time of key generation.
- -C new-comment – The command will specify the comment to describe the key. It can be used for the new and/or existing key. Key operation is not affected by a comment. However, it is used to recognize the key owner, it’s not reliable completely as any value can be applied to it.
- –P – Using the command will update the passphrase of a key. Passphrase helps to encrypt the private key. As passphrase can’t add or update on a command line, it prompts a new passphrase tool to alter it.
- –old-passphrase-file – The old password of the key remains in this file. The command is used when the key is protected by a passphrase.
- –new-passphrase file – This command prompts the new passphrase of the key. It comes in the action either at the time of generating a new key or while applying –P command to change the passphrase.
- -O output-type – This command defines what to give in output. By default, the private key is the output.
Thus, above are the prominent commands of PuTTYgen in Linux operating system. Besides that, there are many other commands available to perform various tasks from the command prompt in Linux at flank speed.
Types of Keys Supported on PuTTYgen
It is important to know the types of key PuTTYgen supports prior to using it. Below are the key types that it currently supports for SSH-2 and SSH-1 protocol:-
- SSH-1 protocol:- For SSH-1 only supports one key i.e. Rivest–Shamir–Adleman (RSA)
- SSH-2 protocol: – SSH-2 supports multiple key types that include – Digital Signature Algorithm (DSA), Elliptic Curve Digital Signature Algorithm (ECDSA) and Ed25519.
The above description is a detailed brief on downloading and running PuTTYgen on all major operating systems. For further details please check the Download PuTTY page.