How to Fix “SSH Too Many Authentication Failures” Error

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Sometimes, while trying to connect to remote systems via SSH, you may encounter the error “Received disconnect from x.x.x.x port 22:2: Too many authentication failures”. In this short article, I will explain how to fix this error in a few simple steps.

Read Also: 4 Ways to Speed Up SSH Connections in Linux

Following is a screenshot of the error I encountered, while using the ssh client.

SSH - Too Many Authentication Failures

SSH – Too Many Authentication Failures

I discovered that this resulted from existence of many ssh identity keys on my machine, and each time I run the ssh client, it would try all my ssh keys known by the ssh-agent and all other keys, when attempting to connect to the remote server (vps2 as shown in the above screenshot). This is the default behavior of ssh.

Since ssh server (sshd) on the remote server expects a particular identity key, the server rejects the connection and ssh client aborts with the above error.

To fix this error, you need to add the IdentitiesOnly with a value of yes, which instructs ssh to only use the authentication identity files specified on the command line or the configured in the ssh_config file(s), even if ssh-agent offers additional identities.

For example:

$ ssh -o IdentitiesOnly=yes vps2

SSH Connection Successful

SSH Connection Successful

Alternatively, if you want this to work for all ssh client connections, you can configure it in your ~/.ssh/config file.

$ vim ~/.ssh/config

Add the following configuration in the file, under the Host * section as shown in the screesnhot.

Host * IdentitiesOnly=yes

Configure Identities in SSH

Configure Identities in SSH

Save the changes in the file and exit it. Now you should be able to run ssh without specifying the option -o IdentitiesOnly=yes on the command line as shown.

$ ssh vps2

SSH Connection Successful

SSH Connection Successful

For more information, see the ssh-config man page.

$ man ssh-config

You might find followng SSH related articles useful.

    1. How to Create SSH Tunneling or Port Forwarding in Linux
    2. How to Change Default SSH Port to Custom Port in Linux
    3. How to Find All Failed SSH Login Attempts in Linux
    4. How to Disable SSH Root Login in Linux
    5. 5 Ways to Keep Remote SSH Sessions Running After Closing SSH

In this short article, I showed how to easily fix the “Received disconnect from x.x.x.x port 22:2: Too many authentication failures” in ssh. If you have any questions, use the comment form below to reach us.

Posted by News Monkey