How to Fix the “Server’s Host Key Did Not Match the Signature Supplied” Error

Welcome to this journal article, Dev. In this article, we will discuss the common error message “Server’s Host Key Did Not Match the Signature Supplied” that you might encounter while trying to connect to a remote server via SSH. We will also provide solutions to fix this error. Here’s what we’ll cover in this article:

Table of Contents

• What is the “Server’s Host Key Did Not Match the Signature Supplied” Error?
• What Causes the “Server’s Host Key Did Not Match the Signature Supplied” Error?
• How to Fix the “Server’s Host Key Did Not Match the Signature Supplied” Error
  • Solution 1: Update Known Hosts File
  • Solution 2: Delete SSH Host Keys
  • Solution 3: Update SSH Client
• Frequently Asked Questions
  • What is an SSH Host Key?
  • How Does the SSH Host Key Verification Work?
  • What Should I Do if the “Server’s Host Key Did Not Match the Signature Supplied” Error Persists After Trying All the Solutions?

What is the “Server’s Host Key Did Not Match the Signature Supplied” Error?

The “Server’s Host Key Did Not Match the Signature Supplied” error is a common error message that you might see when trying to connect to a remote server via SSH. This error occurs when the SSH client cannot verify the host key of the remote server.

What Causes the “Server’s Host Key Did Not Match the Signature Supplied” Error?

There are several reasons why you might see the “Server’s Host Key Did Not Match the Signature Supplied” error:

1. The host key of the remote server has changed since the last time you connected to it.
2. The known_hosts file of your SSH client contains an incorrect or outdated host key.
3. Your SSH client is outdated and cannot recognize the host key of the remote server.

How to Fix the “Server’s Host Key Did Not Match the Signature Supplied” Error

There are several ways to fix the “Server’s Host Key Did Not Match the Signature Supplied” error. In this section, we will discuss three different solutions:

Solution 1: Update Known Hosts File

The first solution is to update the known_hosts file of your SSH client. The known_hosts file contains a list of host keys of the remote servers that you have connected to. If the host key of the remote server has changed, you need to update the known_hosts file to reflect the new host key.

To update the known_hosts file, follow these steps:

1. Open the terminal on your local machine.
2. Type the following command to open the known_hosts file in a text editor:

sudo nano ~/.ssh/known_hosts

3. Find the line that contains the hostname or IP address of the remote server that you are trying to connect to.
4. Delete the line containing the old host key.
5. Try to connect to the remote server again. The SSH client should prompt you to accept the new host key. Type “yes” to accept the new host key and add it to the known_hosts file.

Solution 2: Delete SSH Host Keys

The second solution is to delete the SSH host keys of the remote server from your local machine. This will force the SSH client to retrieve and verify the new host key of the remote server.

To delete the SSH host keys, follow these steps:

1. Open the terminal on your local machine.
2. Type the following command to navigate to the SSH directory:

cd ~/.ssh

3. Type the following command to delete the host key of the remote server:

ssh-keygen -R <hostname or IP address>

4. Try to connect to the remote server again. The SSH client should prompt you to accept the new host key. Type “yes” to accept the new host key and add it to the known_hosts file.

Solution 3: Update SSH Client

The third solution is to update your SSH client to the latest version. Outdated SSH clients might not recognize the host key of the remote server, resulting in the “Server’s Host Key Did Not Match the Signature Supplied” error.

To update your SSH client, follow these steps:

1. Check the version of your SSH client by typing the following command:

ssh -V

2. Visit the website of your SSH client and download the latest version of the client.
3. Install the latest version of the SSH client on your local machine.
4. Try to connect to the remote server again.

Frequently Asked Questions

What is an SSH Host Key?

An SSH host key is a unique identifier that is used to verify the identity of a remote server. When you connect to a remote server via SSH, the server sends its host key to your SSH client. Your SSH client verifies the host key against the known_hosts file to ensure that you are connecting to the legitimate server.

How Does the SSH Host Key Verification Work?

The SSH host key verification works by comparing the host key of the remote server against the known_hosts file in your SSH client. If the host key of the remote server matches the known_hosts file, your SSH client allows the connection. If the host key does not match, your SSH client prompts you to accept the new key and add it to the known_hosts file.

What Should I Do if the “Server’s Host Key Did Not Match the Signature Supplied” Error Persists After Trying All the Solutions?

If the “Server’s Host Key Did Not Match the Signature Supplied” error persists after trying all the solutions, there might be a more serious underlying issue with either your SSH client or the remote server. In this case, you should contact your system administrator or IT support for further assistance.