[CentOS] Date drift and ntpd

[Rick Thomas]

Hi Jason,


On Aug 12, 2010, at 8:01 AM, Jason Pyeron wrote:

> Jul 28 21:42:34 devserver21 ntpd[3475]: frequency error -512 PPM  
> exceeds


This shows that the system clock on devserver21 is driftin too fast  
for NTP to compensate.

Possible causes could be an out-of-spec crystal on that machines, or  
an error in the BIOS (bad frequency divider perhaps) for that  
particular model of machine.

Whatever the cause, it can be compensated for using "adjtimex".  This  
package is not installed by default with Centos 5.5 but you can  
install it easily with "yum install adjtimex".  Then read the man page  
"man 8 adjtimex" and the README in /usr/share/doc/adjtimex*/README and  
follow the directions from there (with particular reference to  
"adjtimex -c" or "adjtimex -a".)

Hope it helps!

Rick