Question: How do you see the exact time when previous commands were entered on a Linux server when you use the "history" command?
Background: Linux by default logs the time and day when commands were issued. (There is a limit to the number of previous commands that stay logged.) The timestamps by default are not visible.
Solution: For the session, until you log out, this will work:
HISTTIMEFORMAT="%d/%m/%y %T "
If you permanently want to see the timestamps associated with the commands entered even after a reboot, you execute this command once:
echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bash_profile ; source ~/.bash_profile
The above works on RedHat, SUSE, and Ubuntu.