Request for Feedback :: Time Mode setting in timemanager

Patrick Williams patrick at
Wed Feb 19 08:51:28 AEDT 2020

On Tue, Feb 18, 2020 at 04:01:00PM -0500, Brad Bishop wrote:
> >>> Please could you help with your thoughts on this ?.. What is the Industry norm on this ?
> >> 
> >> FWIW on our (IBM) system designs we usually hook an RTC up to the BMC, and any host software needing a RTC has to get it via some in-band software interface.  I think I heard somewhere though that often in other systems designs the RTC is connected to the host processors and the BMC doesn’t have access to it.
> > 
> > FB's OCP designs all have the RTC to the Host, so I'm not sure any of
> > this is applicable to us.
> Are there any down sides to designs like this?  I guess if NTP is not an option on the BMC, you are at the mercy of the host firmware if you want correct time.  If NTP is in use on the BMC does an RTC still do anything for you?

There are times that the BMC doesn't know what time it is and reverts
back to 1970.  At least until the network and NTP are up again.  I'm not 
sure the history at why we arrived at this design, honestly.

Patrick Williams
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