ENVIRONMENT

• Zabbix server: 6.0.48
• Zabbix proxy: zabbix-proxy-sqlite3-6.0.48-1.el7.wg.x86_64, EL7, OpenIPMI-libs-2.0.27-1.el7.x86_64
• IPMI interface settings on host: authtype RMCP+, privilege User, port 623
• Affected hardware: Supermicro ARS-110M-NR (board R12SPD-A, Ampere aarch64), 18 hosts
  BMC: Manufacturer ID 10876, Product ID 0x1C5F, firmware 51.02.30.00 and 51.05.07.00 (latest), same result
• Working hardware on the same proxy with the same credentials: Supermicro AS-3015MR-H8TNR, SYS-1028R-WTR, HPE iLO 4/5/6

STEPS TO REPRODUCE
1. Host with IPMI interface pointing to the ARS-110M-NR BMC.
2. Item type "IPMI agent", key ipmi.get (or ipmi.sensor[PS1 Status], IPMI sensor "PS1 Status").
3. Test the item ("Get value") or wait for the poll.

RESULT

• ipmi.get returns: []
• ipmi.sensor[...] items become unsupported: "sensor or control PS1 Status@[<bmc ip>]:623 does not exist"
• zabbix[host,ipmi,available] = 1 (the session itself works)

EXPECTED
The 68 sensors that the BMC exposes are discovered, as ipmitool shows them from the same proxy:

  ipmitool -I lanplus -H <bmc> -U <user> -L USER sdr elist   -> 68 sensors (FAN1..6, PS1/PS2 Status, temperatures, voltages)

ANALYSIS
1. The BMC does not set the "SDR Repository Device" bit in the Get Device ID response
(IPMI 2.0, byte 7 "Additional Device Support", bit 1), and "Provides Device SDRs" is 0:

     ipmitool mc info
       Provides Device SDRs      : no
       Additional Device Support : Sensor Device, SEL Device, FRU Inventory Device, Chassis Device

But it does implement the SDR repository: ipmitool sdr elist / sdr dump read 78 valid records (64 full + 4 compact sensor records, all owner 0x20 LUN 0, entity 0.1; 10 FRU locator records).
2. OpenIPMI reads the main SDR repository only when this bit is set (lib/domain.c, got_guid()):

     if (domain->SDR_repository_support && ipmi_option_SDRs(domain))
         rv = ipmi_sdr_fetch(domain->main_sdrs, sdr_handler, domain);
     else
         rv = get_channels(domain);

So no sensors are created. ipmitool does not check the bit.
3. Confirmed with the OpenIPMI CLI from the Zabbix proxy (same user, privilege, RMCP+):

     openipmish -x "domain open t -wait_til_up lan -U <user> -P <pass> -L user -A rmcp+ <bmc>" -x "entity list t"

• ARS-110M-NR: connection up, MC (0.20) active, 0 sensors, only entity 23.1 (chassis power/reset controls)
• AS-3015MR-H8TNR (works in Zabbix): 22 sensors, 23 entities
  Outputs attached.
  4. We have asked Supermicro to set the bit in the BMC firmware (pending). The BMC update to the latest firmware did not change it.

QUESTIONS / REQUEST

• Is there a way in Zabbix to make the IPMI poller read the SDR repository even when the BMC does not advertise "SDR Repository Device" (configuration option, OpenIPMI option, OEM fixup for this manufacturer/product ID)?
• If not, could this be considered as an improvement: fall back to reading the main SDR repository when the Get Device ID flags report neither SDR repository nor device SDRs (ipmitool and FreeIPMI do this)?

ATTACHMENTS

• mc_info_ars.txt ipmitool mc info (before and after BMC update)
• sdr_elist_ars.txt ipmitool sdr elist, ARS-110M-NR
• sdr_dump_ars.bin ipmitool sdr dump, ARS-110M-NR
• openipmish_ars.txt openipmish output, ARS-110M-NR (0 sensors)
• openipmish_blade.txt openipmish output, AS-3015MR-H8TNR (22 sensors)
• ipmi_get_test.png "Test item" with ipmi.get = []
• proxy_output.txt proxy log, IPMI poller at DebugLevel 4 during one poll of the ARS host