[CentOS] Date drift and ntpd

[Warren Young]

On 8/12/2010 9:03 PM, Les Mikesell wrote:
> ntpd always tries to move the clock fractional seconds at a time

msntp does that, too, if you give the -a flag.  (You have to give either 
-a or -r for it to change the system time at all.)

ntpdate also does this, as long as the delta is less than half a second, 
which it'd better be for an hourly sync schedule, since 0.5s/hr is 139 ppm.

> ntpdate does no sanity check at all

msntp does.  You can configure the min and max error it will correct. 
Its defaults are sane.