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How to Add Date & Time with History in Linux

Introduction

The command history allows the use of words from previous command lines at the command prompt type. This simplifies spelling corrections and the repetition of complicated commands or arguments.

History Command

# history
  850  useradd admin
  851  passwd admin
  852  cd /home/admin/
  853  ls -l
  854  ls -la
  855  top

Edit the file /etc/bashrc add the entry at the end of the file /etc/bashrc

# vi /etc/bashrc
export HISTTIMEFORMAT="%h/%d - %H:%M:%S "

OR
You can also directly execute the following command:

# export HISTTIMEFORMAT="%h/%d - %H:%M:%S "

Now again check the “history” command:

# history
  850  31/08/15 07:22:21 useradd admin
  851  31/08/15 07:22:21 passwd admin
  852  31/08/15 07:22:21 cd /home/admin/
  853  31/08/15 07:22:21 ls -l
  854  31/08/15 07:22:21 ls -la
  855  31/08/15 07:22:21 top

How to Change Time in Linux

Check Date and Time

To check the date and current time of server,use date command:

# date

Wed Jun 17 14:39:35 CEST 2015

Step 1: Modify /etc/localtime File

Edit /etc/localtime to change the timezone data file.

# file /etc/localtime
/etc/localtime: timezone data# file /usr/share/zoneinfo/Asia/Kuala_Lumpur
/usr/share/zoneinfo/Asia/Kuala_Lumpur: timezone data
# date
Wed Jun 17 14:39:35 CEST 2015
# cp /usr/share/zoneinfo/Asia/Kuala_Lumpur /etc/localtime
cp: overwrite `/etc/localtime'? y
# date
Wed Jun 17 14:39:35 CEST 2015

There is also a nice way in order to change the server time using tzselect

# tzselect
Please identify a location so that time zone rules can be set correctly.
Please select a continent or ocean.
1) Africa
2) Americas
3) Antarctica
4) Arctic Ocean
5) Asia
6) Atlantic Ocean
7) Australia
8) Europe
9) Indian Ocean
10) Pacific Ocean
11) none - I want to specify the time zone using the Posix TZ format.
#? 5
Please select a country.
1) Afghanistan 18) Israel 35) Palestine
2) Armenia 19) Japan 36) Philippines
3) Azerbaijan 20) Jordan 37) Qatar
4) Bahrain 21) Kazakhstan 38) Russia
5) Bangladesh 22) Korea (North) 39) Saudi Arabia
6) Bhutan 23) Korea (South) 40) Singapore
7) Brunei 24) Kuwait 41) Sri Lanka
8) Cambodia 25) Kyrgyzstan 42) Syria
9) China 26) Laos 43) Taiwan
10) Cyprus 27) Lebanon 44) Tajikistan
11) East Timor 28) Macau 45) Thailand
12) Georgia 29) Malaysia 46) Turkmenistan
13) Hong Kong 30) Mongolia 47) United Arab Emirates
14) India 31) Myanmar (Burma) 48) Uzbekistan
15) Indonesia 32) Nepal 49) Vietnam
16) Iran 33) Oman 50) Yemen
17) Iraq 34) Pakistan
#? 29
Please select one of the following time zone regions.
1) peninsular Malaysia
2) Sabah & Sarawak
#? 1

Is the above information OK?
1) Yes
2) No
#? 1

You can make this change permanent for yourself by appending the line
TZ='Asia/Kuala_Lumpur'; export TZ
to the file '.profile' in your home directory; then log out and log in again.

Here is that TZ value again, this time on standard output so that you
can use the /usr/bin/tzselect command in shell scripts:
Asia/Kuala_Lumpur

TO set the Hardware Clock of System Time use the command:

# hwclock --systohc

OR

# hwclock -w