This document describes the host-management interfaces of the OpenBMC object structure, accessible over REST.
The system inventory structure is under the /xyz/openbmc_project/inventory
hierarchy.
In OpenBMC the inventory is represented as a path which is hierarchical to the physical system topology. Items in the inventory are referred to as inventory items and are not necessarily FRUs (field-replaceable units). If the system contains one chassis, a motherboard, and a CPU on the motherboard, then the path to that inventory item would be:
inventory/system/chassis0/motherboard0/cpu0
The properties associated with an inventory item are specific to that item. Some common properties are:
Version
: A code version associated with this item.Present
: Indicates whether this item is present in the system (True/False).Functional
: Indicates whether this item is functioning in the system (True/False).
The usual list
and enumerate
REST queries allow the system inventory
structure to be accessed. For example, to enumerate all inventory items and
their properties:
curl -b cjar -k https://${bmc}/xyz/openbmc_project/inventory/enumerate
To list the properties of one item:
curl -b cjar -k https://${bmc}/xyz/openbmc_project/inventory/system/chassis/motherboard
The system sensor structure is under the /xyz/openbmc_project/sensors
hierarchy.
This interface allows monitoring of system attributes like temperature or
altitude, and are represented similar to the inventory, by object paths under
the top-level sensors
object name. The path categorizes the sensor and shows
what the sensor represents, but does not necessarily represent the physical
topology of the system.
For example, all temperature sensors are under sensors/temperature
. CPU
temperature sensors would be sensors/temperature/cpu[n]
.
These are some common properties:
Value
: Current value of the sensorUnit
: Unit of the value and "Critical" and "Warning" valuesScale
: The scale of the value and "Critical" and "Warning" valuesCriticalHigh
&CriticalLow
: Sensor device upper/lower critical threshold boundCriticalAlarmHigh
&CriticalAlarmLow
: True if the sensor has exceeded the critical threshold boundWarningHigh
&WarningLow
: Sensor device upper/lower warning threshold boundWarningAlarmHigh
&WarningAlarmLow
: True if the sensor has exceeded the warning threshold bound
A temperature sensor might look like:
curl -b cjar -k https://${bmc}/xyz/openbmc_project/sensors/temperature/pcie
{
"data": {
"CriticalAlarmHigh": 0,
"CriticalAlarmLow": 0,
"CriticalHigh": 70000,
"CriticalLow": 0,
"Scale": -3,
"Unit": "xyz.openbmc_project.Sensor.Value.Unit.DegreesC",
"Value": 28187,
"WarningAlarmHigh": 0,
"WarningAlarmLow": 0,
"WarningHigh": 60000,
"WarningLow": 0
},
"message": "200 OK",
"status": "ok"
}
Note the value of this sensor is 28.187C (28187 * 10^-3).
Unlike IPMI, there are no "functional" sensors in OpenBMC; functional states are represented in the inventory.
To enumerate all sensors in the system:
curl -b cjar -k https://${bmc}/xyz/openbmc_project/sensors/enumerate
List properties of one inventory item:
curl -b cjar -k https://${bmc}/xyz/openbmc_project/sensors/temperature/ambient
The event log structure is under the /xyz/openbmc_project/logging/entry
hierarchy. Each event is a separate object under this structure, referenced by
number.
BMC and host firmware on POWER-based servers can report event logs to the BMC. Typically, these event logs are reported in cases where host firmware cannot start the OS, or cannot reliably log to the OS.
The properties associated with an event log are as follows:
Message
: The type of event log (e.g. "xyz.openbmc_project.Inventory.Error.NotPresent").Resolved
: Indicates whether the event has been resolved.Severity
: The level of problem ("Info", "Error", etc.).Timestamp
: The date of the event log in epoch time.associations
: A URI to the failing inventory part.
To list all reported event logs:
$ curl -b cjar -k https://${bmc}/xyz/openbmc_project/logging/entry/
{
"data": [
"/xyz/openbmc_project/logging/entry/3",
"/xyz/openbmc_project/logging/entry/2",
"/xyz/openbmc_project/logging/entry/1",
"/xyz/openbmc_project/logging/entry/7",
"/xyz/openbmc_project/logging/entry/6",
"/xyz/openbmc_project/logging/entry/5",
"/xyz/openbmc_project/logging/entry/4"
],
"message": "200 OK",
"status": "ok"
}
To read a specific event log:
$ curl -b cjar -k https://${bmc}/xyz/openbmc_project/logging/entry/1
{
"data": {
"AdditionalData": [
"CALLOUT_INVENTORY_PATH=/xyz/openbmc_project/inventory/system/chassis/powersupply0",
"_PID=1136"
],
"Id": 1,
"Message": "xyz.openbmc_project.Inventory.Error.NotPresent",
"Resolved": 0,
"Severity": "xyz.openbmc_project.Logging.Entry.Level.Error",
"Timestamp": 1512154612660,
"associations": [
[
"callout",
"fault",
"/xyz/openbmc_project/inventory/system/chassis/powersupply0"
]
]
},
"message": "200 OK",
"status": "ok"
}
To delete an event log (log 1 in this example), call the delete
method on the event:
curl -b cjar -k -H "Content-Type: application/json" -X POST \
-d '{"data" : []}' \
https://${bmc}/xyz/openbmc_project/logging/entry/1/action/Delete
To clear all event logs, call the top-level deleteAll
method:
curl -b cjar -k -H "Content-Type: application/json" -X POST \
-d '{"data" : []}' \
https://${bmc}/xyz/openbmc_project/logging/action/deleteAll
With OpenBMC, the Host boot options are stored as D-Bus properties under the
control/host0/boot
path. Properties include
BootMode
and
BootSource
.
The host can be controlled through the host
object. The object implements a
number of actions including power on and power off. These correspond to the IPMI
power on
and power off
commands.
Assuming you have logged in, the following will power on the host:
curl -c cjar -b cjar -k -H "Content-Type: application/json" -X PUT \
-d '{"data": "xyz.openbmc_project.State.Host.Transition.On"}' \
https://${bmc}/xyz/openbmc_project/state/host0/attr/RequestedHostTransition
To power off the host:
curl -c cjar -b cjar -k -H "Content-Type: application/json" -X PUT \
-d '{"data": "xyz.openbmc_project.State.Host.Transition.Off"}' \
https://${bmc}/xyz/openbmc_project/state/host0/attr/RequestedHostTransition
To issue a hard power off (accomplished by powering off the chassis):
curl -c cjar -b cjar -k -H "Content-Type: application/json" -X PUT \
-d '{"data": "xyz.openbmc_project.State.Chassis.Transition.Off"}' \
https://${bmc}/xyz/openbmc_project/state/chassis0/attr/RequestedPowerTransition
To reboot the host:
curl -c cjar -b cjar -k -H "Content-Type: application/json" -X PUT \
-d '{"data": "xyz.openbmc_project.State.Host.Transition.Reboot"}' \
https://${bmc}/xyz/openbmc_project/state/host0/attr/RequestedHostTransition
More information about Host State Management can be found here: https://github.com/openbmc/phosphor-dbus-interfaces/tree/master/xyz/openbmc_project/State
On OpenPOWER systems, the host maintains a record of bad or non-working components on the GARD partition. This record is referenced by the host on subsequent boots to determine which parts should be ignored.
The BMC implements a function that simply clears this partition. This function can be called as follows:
-
Method 1: From the BMC command line:
busctl call org.open_power.Software.Host.Updater \ /org/open_power/control/gard \ xyz.openbmc_project.Common.FactoryReset Reset
-
Method 2: Using the REST API:
curl -b cjar -k -H 'Content-Type: application/json' -X POST -d '{"data":[]}' https://${bmc}/org/open_power/control/gard/action/Reset
Implementation: https://github.com/openbmc/openpower-pnor-code-mgmt