history command lists all executed command on server.
By default output of command is as follows:
989 date
990 history
991 history
992 w
993 top
994 w
995 cd /tmp
996 ls -la
After you add timestamp, it will show you a detailed output with date, time and command.
SSH to server as root and edit file /root/.bash_profile with your favorite editor and add following line:
Export HISTTIMEFORMAT="%F %T "
Now logout and login again and execute history command, you will see
Detailed output as follows:-
root@Server[~]#history
19 04/25/10 08:26:48 hostname
20 04/25/10 08:46:34 history
21 04/25/10 08:46:48 w
22 04/25/10 08:46:50 date
23 04/25/10 08:46:52 cal
24 04/25/10 08:46:53 ls -la
25 04/25/10 08:46:55 top
26 04/25/10 08:47:11 tail -f /var/log/messages
27 04/25/10 08:47:29 history