Time drifting problem on Dell x850

[Andrew Mann]

    We've seen time drift issues with Dell PowerEdge servers of the 
2550, 2650 and 1750 models when under constant moderate to heavy CPU 
load.  Although we run ntpd where possible, in some cases we have 
systems on isolated networks.  As an example, one of our isolated 1750 
systems which has gone a year without a time update was behind by 15 
hours when I recently reset the time.
    I haven't tested for or specifically noticed drifting on the 
PowerEdge 1850, 1855, 2850, 1950, 1955 or 2950 models, but all of the 
systems I have running these PE models are running ntpd.

Andrew

John Hodrien wrote:
> On Wed, 9 Aug 2006, Robert von Bismarck wrote:
>
>   
>> The only workaround we have found is to run ntpdate on the boxes every
>> hour, which is obviously not a *real* solution.
>>     
>
> man ntpdate
>
>         ntpdate - set the date and time via NTP
>
>         Disclaimer:  The  functionality of this program is now available in the
>         ntpd program. See the -q command line option in the ntpd - Network Time
>         Protocol  (NTP)  daemon  page. After a suitable period of mourning, the
>         ntpdate program is to be retired from this distribution
>
>         ... it is important to note that ntpdate with contrived cron scripts is
>         no substitute for the NTP daemon, which uses  sophisticated algorithms
>         to maximize accuracy and reliability while minimizing resource use.
>         Finally, since ntpdate  does  not  discipline  the  host clock frequency
>         as does ntpd, the accuracy using ntpdate is limited.
>
> Why are you avoiding using ntpd?
>
> man ntpd
>
>         ... once the clock has been set, it very rarely strays more than 128 ms,
>         even under  extreme  cases  of  network path congestion and jitter.
>
> jh
>
>