host warm reboots? | Redfish Specification Forum

geissonator
Minnow

Posts: 17

host warm reboots? Jan 14, 2020 22:19:25 GMT

Quote

Post by geissonator on Jan 14, 2020 22:19:25 GMT

We have the following options for managing the state of the system:

"ResetType": {
"enum": [
"On",
"ForceOff",
"GracefulShutdown",
"GracefulRestart",
"ForceRestart",
"Nmi",
"ForceOn",
"PushPowerButton",
"PowerCycle"
],
"enumDescriptions": {
"ForceOff": "Turn off the unit immediately (non-graceful shutdown).",
"ForceOn": "Turn on the unit immediately.",
"ForceRestart": "Shut down immediately and non-gracefully and restart the system.",
"GracefulRestart": "Shut down gracefully and restart the system.",
"GracefulShutdown": "Shut down gracefully and power off.",
"Nmi": "Generate a diagnostic interrupt, which is usually an NMI on x86 systems, to stop normal operations, complete diagnostic actions, and, typically, halt the system.",
"On": "Turn on the unit.",
"PowerCycle": "Power cycle the unit.",
"PushPowerButton": "Simulate the pressing of the physical power button on this unit."
}

One of our use cases is what we call a warm reboot. Where you leave the chassis power on and just reboot the host. At first glance, I don't see where this would fall under the current ResetType's above (unless it's implied in the GracefulRestart)?

Thanks,

Andrew

jautor
Administrator

Posts: 519

host warm reboots? Jan 16, 2020 17:57:22 GMT

Quote

Post by jautor on Jan 16, 2020 17:57:22 GMT

Yes, it's implied by the ForceRestart (and GracefulRestart for that matter). The PC/x86 architecture concepts of "warm" vs. "cold" reboot (Ctrl-Alt-Delete vs hard reset of the system board) are not applicable in (most?) modern system designs so we didn't make that distinction in the list.

So treat "ForceRestart" as essentially 'restart/reboot' - it was named this way to distinguish from the graceful OS shutdown option. In some designs that may also be the equivalent of a "PowerCycle" as well.

Hope that helps,

Jeff

geissonator
Minnow

Posts: 17

host warm reboots? Jan 20, 2020 20:46:09 GMT

Quote

Post by geissonator on Jan 20, 2020 20:46:09 GMT

Hey Jeff, thanks for the response. I'm still a little confused.

Most servers have standby power and chassis power. Standby power is the power required to power on your BMC and maybe a few peripherals to be able to read VPD and such. This power is applied when you plug your system in. Chassis power is applied when you boot the BIOS and is required to get the processor chips and memory running as well as to get your host booted. Chassis power is controlled by the BMC/pgood logic when a boot of the host is requested.

Once your host is booted, we have the concept of being able to reboot your host in a way that will power off the chassis (cold), and then power it back on. We also have the concept of rebooting the host but keeping the chassis power on (warm).

Mixed in with this we have a separate concept of notifying the host of a restart (so they can gracefully shut themselves down) or just forcing a restart without notification. So this gets us the following states and potential Redfish commands?

WarmRebootGraceful == GracefulRestart
ColdRebootGraceful == GracefulShutdown followed by On
ColdRebootNotGraceful == ForceRestart

Or is this Warm vs. Cold concept really just specific to our servers?

Thanks,
Andrew

jleung
Minnow

Posts: 19

host warm reboots? Jan 23, 2020 2:08:03 GMT

Quote

Post by jleung on Jan 23, 2020 2:08:03 GMT

Andrew,
Last year, I had general agreement on a combined state diagram which integrated the chassis power state reboot states with the host restart states. The proposed changes address your issue, along with other issues. I will see about getting the changes into the next schema update.

John

Ramani
Minnow

Posts: 1

host warm reboots? Mar 4, 2020 7:30:35 GMT

Quote

Post by Ramani on Mar 4, 2020 7:30:35 GMT

Jan 16, 2020 17:57:22 GMT jautor said:

Yes, it's implied by the ForceRestart (and GracefulRestart for that matter). The PC/x86 architecture concepts of "warm" vs. "cold" reboot (Ctrl-Alt-Delete vs hard reset of the system board) are not applicable in (most?) modern system designs so we didn't make that distinction in the list.

So treat "ForceRestart" as essentially 'restart/reboot' - it was named this way to distinguish from the graceful OS shutdown option. In some designs that may also be the equivalent of a "PowerCycle" as well.

Hope that helps,

Jeff

Hi Jeff,

So I can consider ForceRestart as Warm boot and PowerCycle as Cold boot. Is that correct?

Thanks,
Ramani

Ramani