When you fail to enter the correct password multiple times while using sudo, your account might get locked for security reasons. This is a security feature to prevent brute force attacks. Here’s how to check and unlock your account using the faillock command.

First, check the status of failed attempts:

sudo faillock

This will show you a list of users and their failed attempts. The output will look something like this:

user:
When                Type  Source                                           Valid
2024-03-19 10:30:00 RHOST 192.168.1.100                                    V
2024-03-19 10:31:00 RHOST 192.168.1.100                                    V

To reset the failed attempts for your user:

sudo faillock --user your_username --reset

Replace your_username with your actual username.

To reset all users’ failed attempts (use with caution):

sudo faillock --reset

After resetting, you should be able to use sudo again. If you want to prevent this from happening in the future, you can:

  1. Use a password manager to store your sudo password
  2. Configure the number of allowed failed attempts in /etc/security/faillock.conf
  3. Set up a longer timeout period between attempts

Remember that this security feature is in place to protect your system, so use these commands responsibly.