Having the correct time on your server is really important especially if you are looking at log files. There is nothing worse than knowing the time something went wrong but not finding it in the log file.
The simple way to solve the problem is to install an NTP service so that the time and date is checked and corrected on a regular basis.
The first thing to check is the current date and time on the server.
The date command will give you this.
You can then check that the time is correct. If it is it maybe that the NTP service is already working.
ps aux | grep ntp
If it is not installed type
sudo apt-get install ntp
Unfortuanatly installing the service does not change the time straight away. To Force a refresh type
sudo service ntp stop
sudo ntpd -gq
sudo service ntp start
Your servers should now give the correct time.