Check redfish-memory

Overview

Checks the state of all memory modules (DIMMs) in a Redfish-compatible server via the Redfish API. Alerts when any memory module reports a degraded or failed state. System-level health (processors, storage, power, temperature, indicator LED, etc.) is deliberately ignored by this check so that a system warning unrelated to memory does not mask the module status; use redfish-systems for that.

Important Notes:

  • Tested on DELL iDRAC and DMTF Simulator

  • A check usually completes within a few seconds, but a slow or retried request can take longer. The bundled Director basket allows a 60 second runtime timeout.

  • This check runs with both HTTP and HTTPS. It uses GET requests only.

  • No additional Python Redfish modules need to be installed.

Data Collection:

  • Queries /redfish/v1/Systems to enumerate system members

  • For each member, follows the Memory link and queries every memory module for its capacity, type, speed, identification and health status

  • Uses HTTP Basic authentication if --username and --password are provided

  • Only evaluates systems and memory modules in „Enabled“ or „Quiesced“ state, so absent or disabled slots are skipped

Fact Sheet

Fact

Value

Check Plugin Download

https://github.com/Linuxfabrik/monitoring-plugins/tree/main/check-plugins/redfish-memory

Nagios/Icinga Check Name

check_redfish_memory

Check Interval Recommendation

Every 5 minutes

Can be called without parameters

Yes

Runs on

Cross-platform

Compiled for Windows

No

Help

usage: redfish-memory [-h] [-V] [--always-ok] [--brief]
                      [--cache-expire CACHE_EXPIRE] [--ignore IGNORE]
                      [--insecure] [--inventory] [--match MATCH] [--no-proxy]
                      [--password PASSWORD] [--retries RETRIES] [--test TEST]
                      [--timeout TIMEOUT] [--url URL] [--username USERNAME]

Checks the state of all memory modules (DIMMs) in a Redfish-compatible server
via the Redfish API. Alerts when any memory module reports a degraded or
failed state. System-level health (processors, storage, power, temperature,
indicator LED, etc.) is deliberately ignored by this check so that a system
warning unrelated to memory does not mask the module status; use `redfish-
systems` for that.

options:
  -h, --help            show this help message and exit
  -V, --version         show program's version number and exit
  --always-ok           Always returns OK.
  --brief               Hide items that are OK and show only those in
                        WARN/CRIT state. Alerting is unaffected: all items
                        still drive the overall check state. Default: False
  --cache-expire CACHE_EXPIRE
                        The amount of time after which the credential/data
                        cache expires, in minutes. Default: 15
  --ignore IGNORE       Ignore items whose name matches this Python regular
                        expression. Case-sensitive by default; use `(?i)` for
                        case-insensitive matching. Can be specified multiple
                        times.
  --insecure            This option explicitly allows insecure SSL
                        connections.
  --inventory           Output the parsed components as JSON on stdout and
                        exit OK, instead of running a health check. Use this
                        to collect a hardware inventory: the JSON is a single
                        object keyed by component type, so the output of
                        several Redfish checks can be merged into one
                        inventory document with `jq --slurp`. Ignores --brief,
                        --match and --ignore. Default: False
  --match MATCH         Only check items whose name matches this Python
                        regular expression. Case-sensitive by default; use
                        `(?i)` for case-insensitive matching. Can be specified
                        multiple times.
  --no-proxy            Do not use a proxy.
  --password PASSWORD   Redfish API password.
  --retries RETRIES     Number of extra attempts if a request to the Redfish
                        API fails, before the check gives up. Helps against an
                        occasionally slow or flaky management controller.
                        Default: 3
  --test TEST           For unit tests. Needs "path-to-stdout-file,path-to-
                        stderr-file,expected-retc".
  --timeout TIMEOUT     Network timeout in seconds. Default: 8 (seconds)
  --url URL             Redfish API URL. Default: https://localhost:5000
  --username USERNAME   Redfish API username.

Usage Examples

./redfish-memory --url=https://bmc --username=redfish-monitoring --password='linuxfabrik'

Output:

Everything is ok, checked memory on 1 member.

Member: Contoso 3500, HostName: web483, SKU: 8675309, SerNo: 437XR1138R2

Module      ! Slot   ! Type ! Size    ! Speed MHz ! Manufacturer ! SerialNumber ! State
------------+--------+------+---------+-----------+--------------+--------------+------
DIMM Slot 1 ! DIMM 1 ! DDR4 ! 32.0GiB !           !              !              ! [OK]
DIMM Slot 2 ! DIMM 2 ! DDR4 ! 32.0GiB !           !              !              ! [OK]
DIMM Slot 3 ! DIMM 3 ! DDR4 ! 32.0GiB !           !              !              ! [OK]

States

  • OK if all enabled memory modules report a healthy state.

  • WARN if an enabled memory module health or health rollup state is „Warning“.

  • CRIT if an enabled memory module health or health rollup state is „Critical“.

  • --always-ok suppresses all alerts and always returns OK.

Perfdata / Metrics

Name

Type

Description

memory_modules

Number

Number of enabled memory modules checked.

memory_modules_not_ok

Number

Number of memory modules whose health is not OK.

For Maintainers

You don’t need a physical server with a real BMC (the management controller that serves the Redfish API, e.g. HPE iLO or Dell iDRAC) to develop or test this plugin. The official DMTF Redfish mockup server serves a static, read-only Redfish tree (including a Memory collection with several DIMMs) over plain HTTP, which is exactly what this GET-only plugin needs.

Run the mockup server and point the plugin at it, from the repository root:

podman run \
    --detach --rm \
    --name lfmp-redfish-mock \
    --publish 5000:8000 \
    docker.io/dmtf/redfish-mockup-server:latest
sleep 3
check-plugins/redfish-memory/redfish-memory --url=http://127.0.0.1:5000 --no-proxy
podman stop lfmp-redfish-mock

Use http://127.0.0.1:5000 rather than http://localhost:5000, because localhost may resolve to IPv6 (::1) while the published container port is bound to IPv4.

The fixtures under unit-test/stdout/ were captured from this mockup server. Each scenario is one set of files named <scenario>-systems, <scenario>-system, <scenario>-memory and <scenario>-dimm-N (one per memory module, in collection order); they are the raw Redfish responses the plugin walks. To simulate a fault, copy a healthy set and edit a module’s Status.Health to Critical or Warning. The offline test suite is run with ./run from the unit-test directory.

Credits, License