# Connect to your Linux instance using PuTTY
You can connect to your Linux instance using PuTTY, a free SSH client for Windows.
If you're running Windows Server 2019 or later, we recommend that you use OpenSSH, an open source connectivity tool for remote login using the SSH protocol.
**Note**
If you receive an error while attempting to connect to your instance, make sure that your instance meets all of the [SSH connection prerequisites](connect-linux-inst-ssh.md#ssh-prereqs-linux-from-linux-macos). If it meets all of the prerequisites, and you're still not able to connect to your Linux instance, see [Troubleshoot issues connecting to your Amazon EC2 Linux instance](TroubleshootingInstancesConnecting.md).
**Topics**
+ [
## Prerequisites
](#putty-prereqs)
+ [Convert your private key using PuTTYgen](#putty-private-key)
+ [
## Connect to your Linux instance
](#putty-ssh)
## Prerequisites
Before you connect to your Linux instance using PuTTY, complete the following tasks.
**Complete the general prerequisites.**
+ Check that your instance has passed its status checks. It can take a few minutes for an instance to be ready to accept connection requests. For more information, see [View status checks](viewing_status.md).
+ [Get the required instance details](connection-prereqs-general.md#connection-prereqs-get-info-about-instance).
+ [Locate the private key and set permissions](connection-prereqs-general.md#connection-prereqs-private-key).
+ [(Optional) Get the instance fingerprint](connection-prereqs-general.md#connection-prereqs-fingerprint).
**Allow inbound SSH traffic from your IP address.**
Ensure that the security group associated with your instance allows incoming SSH traffic from your IP address. For more information, see [Rules to connect to instances from your computer](security-group-rules-reference.md#sg-rules-local-access).
**Install PuTTY on your local computer (if needed).**
Download and install PuTTY from the [PuTTY download page](https://www.chiark.greenend.org.uk/~sgtatham/putty/). If you already have an earlier version of PuTTY installed, we recommend that you download the latest version. Be sure to install the entire suite.
**Convert your private key to PPK format using PuTTYgen.**
You must specify the private key for the key pair that you specified when you launched the instance. If you created the private key in .pem format, you must convert it to a PPK file for use with PuTTY. Locate the private key (.pem file), and then follow the steps in [Convert your private key using PuTTYgen](#putty-private-key).
## (Optional) Convert your private key using PuTTYgen
PuTTY does not natively support the PEM format for SSH keys. PuTTY provides a tool named PuTTYgen, which converts PEM keys to the required PPK format for PuTTY. If you created the key using PEM format instead of PPK format, you must convert your private key (.pem file) into this format (.ppk file) for use with PuTTY.
**To convert your private key from PEM to PPK format**
1. From the **Start** menu, choose **All Programs**, **PuTTY**, **PuTTYgen**.
1. Under **Type of key to generate**, choose **RSA**. If your version of PuTTYgen does not include this option, choose **SSH-2 RSA**.
![\[RSA key in PuTTYgen.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/puttygen-key-type.png)
1. Choose **Load**. By default, PuTTYgen displays only files with the extension `.ppk`. To locate your `.pem` file, choose the option to display files of all types.
![\[Select all file types.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/puttygen-load-key.png)
1. Select your `.pem` file for the key pair that you specified when you launched your instance and choose **Open**. PuTTYgen displays a notice that the `.pem` file was successfully imported. Choose **OK**.
1. To save the key in the format that PuTTY can use, choose **Save private key**. PuTTYgen displays a warning about saving the key without a passphrase. Choose **Yes**.
**Note**
A passphrase on a private key is an extra layer of protection. Even if your private key is discovered, it can't be used without the passphrase. The downside to using a passphrase is that it makes automation harder because human intervention is needed to log on to an instance, or to copy files to an instance.
1. Specify the same name for the key that you used for the key pair (for example, `key-pair-name`) and choose **Save**. PuTTY automatically adds the `.ppk` file extension.
Your private key is now in the correct format for use with PuTTY. You can now connect to your instance using PuTTY's SSH client.
## Connect to your Linux instance
Use the following procedure to connect to your Linux instance using PuTTY. You need the `.ppk` file that you created for your private key. For more information, see [(Optional) Convert your private key using PuTTYgen](#putty-private-key) in the preceding section. If you receive an error while attempting to connect to your instance, see [Troubleshoot issues connecting to your Amazon EC2 Linux instance](TroubleshootingInstancesConnecting.md).
**Last tested version** – PuTTY .78
**To connect to your instance using PuTTY**
1. Start PuTTY (from the **Start** menu, search for **PuTTY** and then choose **Open**).
1. In the **Category** pane, choose **Session** and complete the following fields:
1. In the **Host Name** box, do one of the following:
+ (Public DNS) To connect using your instance's public DNS name, enter *instance-user-name*@*instance-public-dns-name*.
+ (IPv6) Alternatively, if your instance has an IPv6 address, to connect using your instance's IPv6 address, enter *instance-user-name*@*2001:db8::1234:5678:1.2.3.4*.
For information about how to get the username for your instance, and the public DNS name or IPv6 address of your instance, see [Get the required instance details](connection-prereqs-general.md#connection-prereqs-get-info-about-instance).
1. Ensure that the **Port** value is 22.
1. Under **Connection type**, select **SSH**.
![\[PuTTY configuration - Session.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/putty-session-config.png)
1. (Optional) You can configure PuTTY to automatically send 'keepalive' data at regular intervals to keep the session active. This is useful to avoid disconnecting from your instance due to session inactivity. In the **Category** pane, choose **Connection**, and then enter the required interval in **Seconds between keepalives**. For example, if your session disconnects after 10 minutes of inactivity, enter 180 to configure PuTTY to send keepalive data every 3 minutes.
1. In the **Category** pane, expand **Connection**, **SSH**, and **Auth**. Choose **Credentials**.
1. Next to **Private key file for authentication**, choose **Browse**. In the **Select private key file** dialog box, select the `.ppk` file that you generated for your key pair. You can either double-click the file or choose **Open** in the **Select private key file** dialog box.
1. (Optional) If you plan to connect to this instance again after this session, you can save the session information for future use. In the **Category** pane, choose **Session**. Enter a name for the session in **Saved Sessions**, and then choose **Save**.
1. To connect to the instance, choose **Open**.
1. If this is the first time you have connected to this instance, PuTTY displays a security alert dialog box that asks whether you trust the host to which you are connecting.
1. (Optional) Verify that the fingerprint in the security alert dialog box matches the fingerprint that you previously obtained in [(Optional) Get the instance fingerprint](connection-prereqs-general.md#connection-prereqs-fingerprint). If these fingerprints don't match, someone might be attempting a "man-in-the-middle" attack. If they match, continue to the next step.
1. Choose **Accept**. A window opens and you are connected to your instance.
**Note**
If you specified a passphrase when you converted your private key to the PuTTY format, you must provide that passphrase when you log in to the instance.
If you receive an error while attempting to connect to your instance, see [Troubleshoot issues connecting to your Amazon EC2 Linux instance](TroubleshootingInstancesConnecting.md).