The PuTTYgen program is part of PuTTY, an open source networking client for the Windows platform.
- Download and install PuTTY or PuTTYgen.
To download PuTTY or PuTTYgen, go to http://www.putty.org/ and click the You can download PuTTY here link.
- Run the PuTTYgen program.
The PuTTY Key Generator window is displayed.
- Set the Type of key to generate option to SSH-2 RSA.
- In the Number of bits in a generated key box, enter 2048.
- Click Generate to generate a public/private key pair.
As the key is being generated, move the mouse around the blank area as directed.
- (Optional) Enter a passphrase for the private key in the Key passphrase box and reenter it in the Confirm passphrase box.
While a passphrase is not required, you should specify one as a security measure to protect the private key from unauthorized use. When you specify a passphrase, a user must enter the passphrase every time the private key is used.
- Click Save private key to save the private key to a file. To adhere to file-naming conventions, you should give the private key file an extension of
.ppk(PuTTY private key).
.ppkfile extension indicates that the private key is in PuTTY's proprietary format. You must use a key of this format when using PuTTY as your SSH client. It cannot be used with other SSH client tools. Refer to the PuTTY documentation to convert a private key in this format to a different format.
- Select all of the characters in the Public key for pasting into OpenSSH authorized_keys file box.
Make sure you select all the characters, not just the ones you can see in the narrow window. If a scroll bar is next to the characters, you aren't seeing all the characters.
- Right-click somewhere in the selected text and select Copy from the menu.
- Open a text editor and paste the characters, just as you copied them. Start at the first character in the text editor, and do not insert any line breaks.
- Save the text file in the same folder where you saved the private key, using the
.pubextension to indicate that the file contains a public key.
- If you or others are going to use an SSH client that requires the OpenSSH format for private keys (such as the
sshutility on Linux), export the private key:
- On the Conversions menu, choose Export OpenSSH key.
- Save the private key in OpenSSH format in the same folder where you saved the private key in
.ppkformat, using an extension such as
.opensshto indicate the file's content.