Switch SensorCollection to show all sensors as new power/thermal schemas implemented

Switch SensorCollection to show all sensors as new power/thermal schemas implemented

[Gunnar Mills]

Similar discussion has been on the mailing list before: 
https://lists.ozlabs.org/pipermail/openbmc/2020-October/023568.html

The new PowerSubsystem/ThermalSubsystem Redfish schemas can coexist with 
the old Power/Thermal schemas. I suspect we will have both the new and 
old for some time. As we implement the new 
PowerSubsystem/ThermalSubsystem is it okay to switch the behavior of the 
sensor collection from "show sensors that are not covered elsewhere in 
the model" to "show all sensors" as the new 
PowerSubsystem/ThermalSubsystem schemas call for?

I reposted in 
https://redfishforum.com/thread/190/sensorcollection-contain-all-sensors-chassis, 
unless I am missing something I believe Redfish's guidance will be "move 
to a SensorCollection that shows all the sensors". If indeed that is 
their guidance, is everyone okay as we implement the new 
PowerSubsystem/ThermalSubsystem in bmcweb, we move sensor collection to 
show all sensors? Things like webui-vue will have to be updated (not 
sure anything breaks for webui-vue just would have duplicate sensors).

Thanks,
Gunnar

Re: Switch SensorCollection to show all sensors as new power/thermal schemas implemented

[Gunnar Mills]

On 1/11/2021 11:19 AM, Gunnar Mills wrote:
> Similar discussion has been on the mailing list before: 
> https://lists.ozlabs.org/pipermail/openbmc/2020-October/023568.html
> 
> The new PowerSubsystem/ThermalSubsystem Redfish schemas can coexist with 
> the old Power/Thermal schemas. I suspect we will have both the new and 
> old for some time. As we implement the new 
> PowerSubsystem/ThermalSubsystem is it okay to switch the behavior of the 
> sensor collection from "show sensors that are not covered elsewhere in 
> the model" to "show all sensors" as the new 
> PowerSubsystem/ThermalSubsystem schemas call for?
> 
> I reposted in 
> https://redfishforum.com/thread/190/sensorcollection-contain-all-sensors-chassis, 
> unless I am missing something I believe Redfish's guidance will be "move 
> to a SensorCollection that shows all the sensors". If indeed that is 
> their guidance, is everyone okay as we implement the new 
> PowerSubsystem/ThermalSubsystem in bmcweb, we move sensor collection to 
> show all sensors? Things like webui-vue will have to be updated (not 
> sure anything breaks for webui-vue just would have duplicate sensors).

Redfish's reply was "My statement from 18 months ago is no longer our 
recommendation. That was before we proposed to re-factor the Power and 
Thermal schemas to use the Sensor model. And that continues to be our 
direction. So in that light, we want everything that counts as a 
"sensor" to be part of the Sensor collection so that generic monitoring 
software can be built to harvest sensor data across the Redfish model.

Even if an implementation hasn't decided to adopt the (still a 
work-in-progress) PowerSubystem and ThermalSubsystem models, the 
underlying temperature and fan sensors can be rendered as Redfish Sensor 
resources as a good middle ground (and a step in the right direction for 
future work).".

Based on that reply, I propose we move Redfish SensorCollection to show 
all sensors. Let me know if anyone objects.

Thanks,
Gunnar

Re: Switch SensorCollection to show all sensors as new power/thermal schemas implemented

[Deepak Kodihalli]

Hi Gunnar,

On Tue, Jan 19, 2021 at 11:51 PM Gunnar Mills <gmills@linux.vnet.ibm.com> wrote:
>
> On 1/11/2021 11:19 AM, Gunnar Mills wrote:
> Based on that reply, I propose we move Redfish SensorCollection to show
> all sensors. Let me know if anyone objects.

Where would the sensor collection be rooted at?
/redfish/v1/chassis/{ID}/sensors? If so, would this also contain
sensors accessible to the system software (some CPU/DIMM sensors for
eg)?

Thanks,
Deepak

Re: Switch SensorCollection to show all sensors as new power/thermal schemas implemented

[Gunnar Mills]

On 1/19/2021 9:53 PM, Deepak Kodihalli wrote:
> 
> Where would the sensor collection be rooted at?
> /redfish/v1/chassis/{ID}/sensors? 


Late reply. Yes. Sensors are associated to a chassis via an association.
https://github.com/openbmc/docs/blob/919a7b6816a5f16aa72d298e81e0756d95d5031e/architecture/sensor-architecture.md#association-type-1-linking-a-chassis-to-all-sensors-within-the-chassis

https://gerrit.openbmc-project.xyz/c/openbmc/bmcweb/+/40169 is the code 
for moving bmcweb to all sensors in the sensor collection.


If so, would this also contain
> sensors accessible to the system software (some CPU/DIMM sensors for
> eg)?


Yes, it could. There is nothing in the Redfish spec that prevents that. 
The definition of what a sensor is in Redfish is very broad.
If you need additional "ReadingTypes", I'm sure Redfish would be willing 
to add with a use case.

https://redfish.dmtf.org/schemas/v1/Sensor.v1_2_0.json

Hope this helps,
Gunnar