Enable Timestamps in History Command

History command is used to check the history of commands with command number and command but sometime when we need to check the date and time of the command entered then we need to enable timestamps but how :)

#To view the history commands
root@GW:~# history | more
 1030  route -n
 1031  ifconfig eth7 down
 1032  ifconfig eth7 up


The list of history command is found in your home directory with hidden filename .bash_history. Here is the partial view of the file

root@GW:~# cat .bash_history
route -n
ifconfig eth7 down
ifconfig eth7 up

Now enabling timestamps using following command
 root@GW:~# export HISTTIMEFORMAT="%F %T "

And here is the output now
root@GW:~# history | more
 1030  2014-01-13 13:43:14 route -n
 1031  2014-01-13 13:43:14 ifconfig eth7 down
 1032  2014-01-13 13:43:14 ifconfig eth7 up

This will temporarily enable timestamps for this sessions To make it permanent, Please do following 
root@GW:~# vi ~/.bashrc and enter the following lines @ top

HISTTIMEFORMAT="%F %T "

If you want to disable history command list temporarily then you can set HISTSIZE=0 in terminal and if you want to permanently disable then make HISTSIZE = 0 in .bashrc file.