Power Algorithm - Harvest (2024)

Gathering power metrics requires a cluster with:

ONTAP versions 9.6+
REST enabled, even when using the ZAPI collector. After granting REST permissions, restart Harvest.

REST is required because it is the only way to collect chassis field-replaceable-unit (FRU) information via theREST API /api/private/cli/system/chassis/fru.

How does Harvest calculate cluster power?¶

Cluster power is the sum of a cluster's node(s) power + the sum of attached disk shelve(s) power.

Redundant power supplies (PSU) load-share the total load.With n PSUs, each PSU does roughly (1/n) the work(the actual amount is slightly more than a single PSU due to additional fans.)

Node power¶

Node power is calculated by collecting power supply unit (PSU) power, as reported by REST /api/private/cli/system/environment/sensors or by ZAPI environment-sensors-get-iter.

When a power supply is shared between controllers,the PSU's power will be evenly divided across the controllers due to load-sharing.

For example:

FAS2750 models have two power supplies that power both controllers. Each PSU is shared between the two controllers.
A800 models have four power supplies. PSU1 and PSU2 power Controller1 and PSU3 and PSU4 power Controller2. Each PSU provides power to a single controller.

Harvest determines whether a PSU is shared between controllers by consulting the connected_nodes of each PSU,as reported by ONTAP via /api/private/cli/system/chassis/fru

Disk shelf power¶

Disk shelf power is calculated by collecting psu.power_drawn, as reported by REST, via/api/storage/shelves or sensor-reading, as reported by ZAPI storage-shelf-info-get-iter.

The power for embedded shelvesis ignored, since that power is already accounted for in the controller's power draw.

Examples¶

FAS2750¶

# Power Metrics for 10.61.183.200## ONTAP version NetApp Release 9.8P16: Fri Dec 02 02:05:05 UTC 2022## Nodessystem show Node | Model | SerialNumber ----------------------+---------+---------------cie-na2750-g1344-01 | FAS2750 | 621841000123 cie-na2750-g1344-02 | FAS2750 | 621841000124## Chassissystem chassis fru show ChassisId | Name | Fru | Type | Status | NumNodes | ConnectedNodes ---------------+-----------------+---------------------+------------+--------+----------+-------------------------------------------021827030435 | 621841000123 | cie-na2750-g1344-01 | controller | ok | 1 | cie-na2750-g1344-01 021827030435 | 621841000124 | cie-na2750-g1344-02 | controller | ok | 1 | cie-na2750-g1344-02 021827030435 | PSQ094182201794 | PSU2 FRU | psu | ok | 2 | cie-na2750-g1344-02, cie-na2750-g1344-01 021827030435 | PSQ094182201797 | PSU1 FRU | psu | ok | 2 | cie-na2750-g1344-02, cie-na2750-g1344-01## Sensorssystem environment sensors show(filtered by power, voltage, current) Node | Name | Type | State | Value | Units ----------------------+---------------+---------+--------+-------+--------cie-na2750-g1344-01 | PSU1 12V Curr | current | normal | 9920 | mA cie-na2750-g1344-01 | PSU1 12V | voltage | normal | 12180 | mV cie-na2750-g1344-01 | PSU1 5V Curr | current | normal | 4490 | mA cie-na2750-g1344-01 | PSU1 5V | voltage | normal | 5110 | mV cie-na2750-g1344-01 | PSU2 12V Curr | current | normal | 9140 | mA cie-na2750-g1344-01 | PSU2 12V | voltage | normal | 12100 | mV cie-na2750-g1344-01 | PSU2 5V Curr | current | normal | 4880 | mA cie-na2750-g1344-01 | PSU2 5V | voltage | normal | 5070 | mV cie-na2750-g1344-02 | PSU1 12V Curr | current | normal | 9920 | mA cie-na2750-g1344-02 | PSU1 12V | voltage | normal | 12180 | mV cie-na2750-g1344-02 | PSU1 5V Curr | current | normal | 4330 | mA cie-na2750-g1344-02 | PSU1 5V | voltage | normal | 5110 | mV cie-na2750-g1344-02 | PSU2 12V Curr | current | normal | 9170 | mA cie-na2750-g1344-02 | PSU2 12V | voltage | normal | 12100 | mV cie-na2750-g1344-02 | PSU2 5V Curr | current | normal | 4720 | mA cie-na2750-g1344-02 | PSU2 5V | voltage | normal | 5070 | mV## Shelf PSUsstorage shelf showShelf | ProductId | ModuleType | PSUId | PSUIsEnabled | PSUPowerDrawn | Embedded ------+-----------+------------+-------+--------------+---------------+--------- 1.0 | DS224-12 | iom12e | 1,2 | true,true | 1397,1318 | true### Controller Power From Sum(InVoltage * InCurrent)/NumNodesPower: 256W

AFF A800¶

# Power Metrics for 10.61.124.110## ONTAP version NetApp Release 9.13.1P1: Tue Jul 25 10:19:28 UTC 2023## Nodessystem show Node | Model | SerialNumber ----------+----------+-------------a800-1-01 | AFF-A800 | 941825000071 a800-1-02 | AFF-A800 | 941825000072## Chassissystem chassis fru show ChassisId | Name | Fru | Type | Status | NumNodes | ConnectedNodes ----------------+----------------+-----------+------------+--------+----------+---------------SHFFG1826000154 | 941825000071 | a800-1-01 | controller | ok | 1 | a800-1-01 SHFFG1826000154 | 941825000072 | a800-1-02 | controller | ok | 1 | a800-1-02 SHFFG1826000154 | EEQT1822002800 | PSU1 FRU | psu | ok | 1 | a800-1-02 SHFFG1826000154 | EEQT1822002804 | PSU2 FRU | psu | ok | 1 | a800-1-02 SHFFG1826000154 | EEQT1822002805 | PSU2 FRU | psu | ok | 1 | a800-1-01 SHFFG1826000154 | EEQT1822002806 | PSU1 FRU | psu | ok | 1 | a800-1-01## Sensorssystem environment sensors show(filtered by power, voltage, current) Node | Name | Type | State | Value | Units ----------+---------------+---------+--------+-------+------a800-1-01 | PSU1 Power In | unknown | normal | 376 | W a800-1-01 | PSU2 Power In | unknown | normal | 411 | W a800-1-02 | PSU1 Power In | unknown | normal | 383 | W a800-1-02 | PSU2 Power In | unknown | normal | 433 | W## Shelf PSUsstorage shelf showShelf | ProductId | ModuleType | PSUId | PSUIsEnabled | PSUPowerDrawn | Embedded ------+-------------+------------+-------+--------------+---------------+--------- 1.0 | FS4483PSM3E | psm3e | | | | true ### Controller Power From Sum(InPower sensors)Power: 1603W