How do I check login attempts in Ubuntu?

2 Answers

1. Filter for brute-force interactive SSH logins. Open a terminal, and type the below; if it’s longer than 1 page you will be able to scroll up and down; type q to exit: grep sshd.*Failed /var/log/auth.log | less. …
2. Look for failed connections (i.e. no login attempted, could be a port scanner, etc. ):

Where can I find login attempts?

Open Event Viewer in Active Directory and navigate to Windows Logs> Security. The pane in the center lists all the events that have been setup for auditing. You will have to go through events registered to look for failed logon attempts.