It is one of the settings kept by AIX security administration.

lsuser -a time_last_login tty_last_login username is the most specific.

As root you can also examine the files in /etc/security manually. However, for security reasons, it is better to use the commands.

A lowerlevel command for user ABCD would be

grep -p ABCD /etc/security/lastlog

This command can be performed by people in the group security (i.e. no root access required).

michael@x054:[/home/michael]grep -p ABCD /etc/security/lastlog
ABCD:
        time_last_unsuccessful_login = 1179043725
        tty_last_unsuccessful_login = ssh             
        host_last_unsuccessful_login = 10.161.36.80                                   
        unsuccessful_login_count = 40       
        time_last_login = 1166623181
        tty_last_login = ftp             
        host_last_login = loopback