{"id":2444,"date":"2023-04-30T09:52:35","date_gmt":"2023-04-30T09:52:35","guid":{"rendered":"https:\/\/draculaservers.com\/tutorials\/?p=2444"},"modified":"2023-06-06T06:57:23","modified_gmt":"2023-06-06T06:57:23","slug":"ssh-host-key-verification-error-fix","status":"publish","type":"post","link":"https:\/\/draculaservers.com\/tutorials\/ssh-host-key-verification-error-fix\/","title":{"rendered":"Fix: SSH Connection Problem With Host Key Verification Failed Error"},"content":{"rendered":"

The \u201cHost Key Verification Failed\u201d error occurs when a known host has changed its authentication key or when a man-in-the-middle attack occurs in your network. If you are having this SSH Connection problem, then worry not, as this guide has got you covered.<\/p>\n

If you want to jump directly at the solution, then scroll down to the solutions section. Otherwise, let\u2019s begin with some basics related to this problem.<\/p>\n

What Does the \u201cHost Key Verification Failed\u201d Mean?<\/h2>\n

Whenever you try connecting to an SSH Server, you are prompted with a confirmation asking you if you are connecting to the correct server and also if you trust the server. After confirming your action (typically by typing \u201cyes<\/strong>\u201d), the information about this remote server or SSH Server is stored inside the \u201cknown_hosts<\/strong>\u201d file. This contains the information about the Authentication Key as well as your other preferences for that particular server.<\/p>\n

\"The<\/a><\/p>\n

The next time you try connecting to the same remote host, the information is taken from the \u201cknown_hosts\u201d file. If there are no changes, then the connection is successful. However, if the Host has made changes in the Remote Server, and the configuration settings in the known_hosts file are not updated, then the connection returns the \u201cHost Key Verification Failed<\/strong>\u201d Error.<\/p>\n

This error can also occur when someone is trying to deceive you into logging in to their dummy\/fake remote server to get the details of the SSH Connection:<\/p>\n

\"Error<\/a><\/p>\n

Now that we understand the error. Let\u2019s head over to its solution.<\/p>\n

How to Fix SSH Host Key Verification Failed Error?<\/h2>\n

To fix this error, you need to make changes to the \u201cknown_hosts<\/a>\u201d file. Apart from the changes, you can actually delete the known_hosts file from your system. Let\u2019s go through these methods one by one.<\/p>\n

Method 1: Delete The Old Key From the known_hosts File<\/h3>\n

The first method is simple if the SSH host has updated or changed their authentication key. Then you need to remove the old key from the known_hosts file. For this, you can utilize the ssh_keygen. To do this, open up a new terminal and use the following syntax:<\/p>\n

ssh-keygen -R HOSTNAME<\/pre>\n
However, make sure to replace the \u201cHOSTNAME\u201d with the actual hostname (or IP Address) of the remote host that you are trying to connect to. Afterward, retry the connection with the remote host using the updated key, and the connection will be successful.<\/p>\n
Method 2: Manually Remove the Key Using the sed Command<\/h3>\n
Typically, whenever you encounter this error, the error prompt will contain the line number on which the information or key information is placed for that particular host. Suppose that the line number is \u201c15\u201d within the known_hosts file. What you have to do is to delete line 15 from the known_hosts file using the following command:<\/p>\n
sed -i '10' ~.ssh\/known_hosts<\/pre>\n
Alternatively, you can also use the Vim editor. To open up the known_hosts file with the pointer on the exact line that you need to delete, use the following command:<\/p>\n
vim +10 known_hosts<\/pre>\n
Here, \u201c+10<\/strong>\u201d defines the line number. Once inside the Vim editor:<\/p>\n