Modeling the host interface for a system

Yes, the HostInterface resource and the related EthernetInterface are used to describe the Manager (BMC) to host OS / hypervisor interface.

Jeff

Sharing additional context to the question above.


Any external management client can communicate with the Host(KVM or any other Hypervisor) using the HOST IP address.

Have the two proposed solutions to model the Host's(kvm/hypervisor) ethernet interface as follows,

Option 1)

Manager-> HostInterfaces->Hostinterface
HostInterfaceType: NetworkHostInterface
InterfaceEnabled: false
ExternalAccessible: true
Configure the "HostEthernetInterfaces"

"InterfaceEnabled: false" - To indicate the BMC is restricted to access this host interface
"ExternalAccessible: true" - To indicate this interface can be accessed externally from any other management client

Option 2)

Under /redfish/v1 we create another System resource; say "Hypervisor" and then configure the Ethernet interface under this System Resource.
This will mean, at redfish root level there would be two Systems for the Server.
1) System which represents the whole server
2) System which represents only the Hypervisor(KVM/propreitary)

For Option 2) , the following additional two items also need to be defined -

1/ Relationship of Hypervisor being a part of the overall Server system
We can do this by having a link property to connect the overall System to the Hypervisor Syestem which needs to be newly defined in the spec.


PS: For the Option 1), the HostInterface resource has the Network Protocol property.

Please let me know your views on which option can be a more appropriate solution. Would like to hear if there are other alternatives too.

If you're not using the Redfish Host Interface (DSP0270), but rather an LPC/non-Redfish-defined interface, then you don't have a "HostInterface" instance as far as the Redfish data model is concerned.

So you'd model a ComputerSystem with an EthernetInterface to report the host-to-network connectivity, and an EthernetInterface under your Manager instance for the BMC-to-network. If you need to report or configure anything about your LPC interface (your BMC-to-host), that would be an OEM resource...

When thinking about how things get modeled and rendered in Redfish, we try to remove the internal architectural details when they have no impact on the user (or, the user can't do anything about it anyway). In your case, the use of the NCSI switch is just such a detail - looking from the outside and treating the system as a "black box", that hardware is essentially invisible to the user.

Hope that helps,

Jeff

If you really do need to show "pending changes" for that resource, then you would use a Settings resource on that EthernetInterface to show pending changes.

However, given your use case, it might not be entirely beneficial to show this level of detail. If the system is offline, there really isn't much of a difference between the pending changes and what's currently applied since the interface itself will be unusable.