Request for Feedback :: Time Mode setting in timemanager

Patrick Williams patrick at
Wed Feb 19 07:52:31 AEDT 2020

On Tue, Feb 18, 2020 at 03:34:02PM -0500, Brad Bishop wrote:
> > On Feb 18, 2020, at 3:25 PM, Patrick Williams <patrick at> wrote:

> > Most of these design points came from considering how it might be best
> > for a cloud provider, like Rackspace, we were originally designing some
> > of this code for.
> > 
> > If I'm leasing the host processor from you, I don't necessarily trust
> > your time infrastructure and might want to use my own.
> Agreed but what does this have to do with what is going on, on the BMC?

When the BMC owns the hardware RTC, { Manual , Host } is the only mode
that allows the Host to utilize the RTC hardware without being subject
to the provider's time infrastructure.

What we talked about way back when this was implemented is that someone
super paranoid could use an inband IPMI call to get these settings,
confirm it was in { Manual , Host } mode, and know by design that it
won't ever change out from underneath without a reboot.  If it isn't
part of the design, I have no way of knowing if the provider (or someone
who has compromised their management infrastructure) has reverted time
control back to the BMC while I'm running.

Patrick Williams
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