banshee/hardware-collection/hardware/redfish/https/memory

Memory of a server, by Redfish

Returns, for each memory module a server's management card serves by Redfish, its health and its size, and the total memory of the server. Three watches are offered, each one set on the probe.

Versions

Generic: written for the ComputerSystem and Memory schemas of DMTF Redfish, whose fields read here have kept their form since the first versions (2016). Any management card that serves them: Dell iDRAC, HPE iLO, Supermicro, Lenovo XCC, OpenBMC. Hence the common level.

How it works

The collector reads, the account in Basic, GET https://<host:address>/redfish/v1/Systems, each system it lists, its Memory collection, then each module in it.

{"Id": "DIMM.Socket.A1", "Name": "DIMM A1", "CapacityMiB": 32768, "Status": {"State": "Enabled", "Health": "OK"}}

A module is named by its Name (DIMM A1, proc1dimm1); when two bear the same name, each is named by its name followed by its Id.
health is the module's HealthRollup or Health, in lower case (ok, warning, critical), unknown when it gives neither. A module with too many corrected errors, or disabled by the firmware, reads warning or critical.
size is its CapacityMiB.
total is the MemorySummary.TotalSystemMemoryGiB of the systems, added up; the sum of the modules when no system gives it. It is what the firmware counts at boot: a module it disables lowers it.
A slot the card says Absent is empty: it is left out (HPE iLO lists every slot).
A code 401 or 403 stops the collector misconfigured; any other code but 200 stops it unreachable, with the path it was reading. A card that serves no module stops it misconfigured.

The password comes from protocol:http:password, a secret variable: it only goes in the Basic header. Redfish only reads with GET.

Prerequisites

The management card's address as the host's address, reachable from the poller in HTTPS (443); its certificate trusted by the TLS profile of the probe (protocol:http:fingerprint, or its authority under protocol:tls:authorities).
A read-only account on the card (the ReadOnly role of Redfish), in protocol:http:user and protocol:http:password.

Outputs

Name	Label	Unit	Per instance
`health`	Health	—	yes, per memory module
`size`	Size	MiB	yes, per memory module
`total`	Total memory	GiB	no

Watches

Name	Title	Kind	Defaults	Checked by default
`unhealthy`	Memory module degraded	state to avoid, on `health`	warning on `warning`, critical on `critical`	yes
`total`	Unexpected total memory	expected value, on `total`	no size set: it raises nothing until the expected size, in GiB, is set on the probe	no
`missing`	Memory module missing	expected instances, on `health`	no module named: it raises nothing until names are set on the probe	no

Limits

The address is written into the URL as is: an IPv6 address must be given as a name.
One request per module: a server with many modules takes as many round trips.
A collection cut into pages (Members@odata.nextLink) is read on its first page only.
A JSON null reads as '' in Keen, which the collector takes for "not given": a CapacityMiB written null is not returned, a Health written null reads unknown, which raises nothing.
Not checked against a card: the paths and fields are those of the DMTF Redfish schemas (ComputerSystem, Memory), read on redfish.dmtf.org.