Set date and time in Linux

There are few ways to set the date and time on Linux command line. In order to do this, you must login as root and execute the following methods as follow:

For you to remember the syntax, issue the command “date” first

[root@linuxtechtips ~]# date

Mon Aug 20 18:30:29 SGT 2012

Let say you want to change it to Sept 6, 2012, 3pm, just follow the pattern above

[root@linuxtechtips ~]# date 090615002012

Thu Sep 6 15:00:00 SGT 2012

where as:

09 = month (September)

06 = day

15 = hour

00 = min

2012 = year

Now it’s set, as simple as that:

[root@linuxtechtips ~]# date

Thu Sep 6 15:00:01 SGT 2012

Another example, you want it to change to 20th of December, 2012, 10:45pm

[root@linuxtechtips ~]# date 122022452012

Thu Dec 20 22:45:00 SGT 2012

Viola!!!

[root@linuxtechtips ~]# date

Thu Dec 20 22:45:03 SGT 2012

Now if you want to challenge yourself, then you can use this as well:

Using our example date above, use the date command with –set or -s options

[root@linuxtechtips ~]# date -s "6 Sept 2012 15:00:00"

Thu Sep 6 15:00:00 SGT 2012

Extra tip: To set the hardware clock to the current system time, use:

[root@linuxtechtips ~]# hwclock --systohc

If the other way around, to set the system time from the hardware clock

[root@linuxtechtips ~]# hwclock --hctosys

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