Linux,Getting,the,Correct,Time computer Linux Getting the Correct Time
----------------------------------------------------------Permission is granted for the below article to forward,reprint, distribute, use for ezine, newsletter, website,offer as free bonus or part of a product for sale as longas no changes a Gone are those times when the companies and the organisations didn't need a hi-tech system to handle them. Owing to the considerable increase in the business sector and thus, an enormous increase in the complexity of the organisational struc
Normal 0 false false false EN-GB X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable{mso-style-name:"Table Normal";mso-tstyle-rowband-size:0;mso-tstyle-colband-size:0;mso-style-noshow:yes;mso-style-priority:99;mso-style-qformat:yes;mso-style-parent:"";mso-padding-alt:0cm 5.4pt 0cm 5.4pt;mso-para-margin-top:0cm;mso-para-margin-right:0cm;mso-para-margin-bottom:10.0pt;mso-para-margin-left:0cm;line-height:115%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:"Calibri","sans-serif";mso-ascii-font-family:Calibri;mso-ascii-theme-font:minor-latin;mso-fareast-font-family:"Times New Roman";mso-fareast-theme-font:minor-fareast;mso-hansi-font-family:Calibri;mso-hansi-theme-font:minor-latin;}Ensuring a computer isnot only displaying the correct time but that it is being maintained accuratelyis not as straight-forward as it first sounds.Most Linux systemshave two clocks. The hardware clock, also known as the CMOS of Bios clock, isusually a simple crystal oscillator with battery back-up that maintains timewhen your system is off or boots up. This clock is usuallylocated on the motherboard andwill run all the time, however these clock chips tend to lose time as thecomputer ages and the battery weakens. The other clock, thesystem clock, is a software clock and it starts when you boot up your systemoften getting an initial time from the hardware clock. System clocks keep timeby adding seconds on to a prime epoch, a base time that for Linux and Unix, beganat midnight on January 1, 1970. However, the hardwareclock is a cheap electronic oscillator and cannot maintain time to any usefuldegree of accuracy. They often drift several seconds a day which for day-to-dayprocess is probably adequate but with time sensitive applications it can causeserious problems.A better way is to setthe system clock using the time from a NTP (Network Time Protocol) time server.These dedicated time servers get a UTC (Coordinated Universal Time) time from anatomic clock which are the most accurate time keepers in the world, not losinga second in time in several millions of years. Dedicated NTP serversuse either a radio receiver to pick-up a radio time and frequency broadcastwhich are transmitted by several national laboratories or by using the timingsignal broadcast from the GPS network.Linux uses a NTPservice called NTP Daemon (ntpd). This uses NTP to adjust the system clock forany drift in time as it frequently check the UTC time source.To configure the NTPdaemon the ntp.conf file in the /etc directory can be used. From here more thanone time server can be used as a reference and also the frequency it is checkedcan also be altered.
Linux,Getting,the,Correct,Time