Category: sysadmin Generated on 2016-09-29
source: https://opensource.com/business/16/6/managing-passwords-security-linux
The last command shows the number of successfull login attempts.
It writes to /var/log/wtmp.
The lastb command shows the number of unsuccessful login attempts.
It writes to /var/log/btmp.
If this file have been zeroed out, you have a problem.