Antw: Re: Q: "dn: cn=Uptime,cn=Time,cn=Monitor" non-monotonic occasionally?
>> "Brett @Google" <brett.maxfield(a)gmail.com>
schrieb am 29.04.2016 um 11:50 in
Nachricht
<CAJiMZ95aOoN7pVAHKDzmamzkQCL9J6xKQoanSQCv=eq3daz0Cg(a)mail.gmail.com>:
On Thu, Apr 28, 2016 at 6:48 PM, Ulrich Windl <
Ulrich.Windl(a)rz.uni-regensburg.de> wrote:
> Hi!
>
> I'm running a NRPE monitor that monitors openLDAP. To compute delta
> values, the NRPE plugin stores the "dn: cn=Uptime,cn=Time,cn=Monitor"
> reported by openLDAP to compare it with the current value (to build the
> time difference). If the time difference is negative, the plugin reports a
> "server restart" event.
>
> So far, so good...
>
> However, very rarely (once every few weeks) a false server restart is
> reported. Viewing the historic logs, I can only assume that openLDAP
> reports a bad uptime value now and then. Could this be?
>
If uptime is a calculation based on the system clock, is there some process
such as ntpd or vmware tools, periodically updating the system clock,
sometimes backwards ?
It should not, but the time could behave odd (jump) immediately after migration. I'll
have to investigate this further.
If so, maybe look for an option to limit backwards updates.
Cheers
Brett