Superdome2 16 server I2C busses error

akash7 — Fri, 10 Apr 2026 03:51:17 GMT

Hi Team,

I have superdome2 16s server and getting an error in the management buses/I2C buses error. Last night we replaced the IOX 9 box, but the IO cards are not replaced . Please suggest.

IOX 9:

Health: Degraded
Power:
Bay 1: On
Bay 2: On
Unit Identification LED: Off
Diagnostic Status:
Internal Data OK
Management Processor OK
Thermal Warning OK
Thermal Danger OK
Cooling OK
Device Failure OK
I2C Buses ------------Failed
Firmware Mismatch OK
Indicted OK

Power Subsystem:
Status: OK
Redundancy State: Redundant
Power Capacity: 1500 Watts DC
Present Power: 91 Watts AC
PS 1: OK
PS 2: OK

Cooling Subsystem:
Status: OK
Fans Good/Wanted/Needed: 4/4/3
Fan 1: 6780 RPM (79%)
Fan 2: 6960 RPM (81%)
Fan 3: 6660 RPM (77%)
Fan 4: 6780 RPM (79%)

Xfabric Link Status:
Link 1: OK
Link 3: OK
Link 4: OK
Link 6: OK

IO Slots Status:
Bay Slot Status
---- ---- -----------------
1 1 OK
1 2 OK
1 3 OK
1 4 OK
1 5 OK
1 6 OK
2 1 OK
2 2 OK
2 3 OK
2 4 OK
2 5 OK
2 6 OK

Thermal Sensor Status:
Locale Status Temp Caution Critical
--------------------------------- ------ -------- ------- --------
IOX Ambient Zone OK 24C/ 75F 45C 50C

Re: Superdome2 16 server I2C busses error

akash7 — Thu, 09 Apr 2026 07:15:16 GMT

Please reply. Why has this error not been resolved after the IOX box replacement? How to find the exact error and solution.

Re: Superdome2 16 server I2C busses error

Rakshitha_K — Thu, 09 Apr 2026 13:39:21 GMT

Hi @akash7 ,

On Superdome 2, “I2C Buses: Failed” on an IOX generally means something on the internal I2C management chain is stuck or not responding. Because I2C is a shared bus, a single faulty device can pull the bus low and make the entire shelf report failed. Since you replaced the IOX 9 chassis but reused the existing I/O cards, the most likely causes are:

- A faulty or marginal PCIe I/O card in IOX 9 that’s holding the I2C lines
- A card with incompatible/old firmware causing I2C timeouts
- A seating/connector issue or contamination in a slot
- Less likely (but possible): a bad fan/FRU on the shelf or a backplane issue in the replacement unit, though other sensors look OK

Recommended isolation steps

Please schedule a brief maintenance window and do the following in order:

1) Soft reset the IOX shelf
- From the Superdome 2 OA/management interface, perform a reset of IOX 9’s management controller or power-cycle the IOX 9 shelf if there is a supported option. Sometimes an I2C bus lock clears with a controller reset.
- If there’s no software reset option, you can perform a cold power cycle by removing power to the shelf (both PSUs) for at least 60 seconds, then reapply power. Do this only during a window and after confirming redundancy and impact.

2) Reseat external items
- Verify and reseat the Xfabric cables to IOX 9 and the Xfabric modules on both ends. Your links show OK, but it’s quick to eliminate a marginal connection.
- Check both IOX 9 PSUs and fan trays: reseat them. Ensure both fans spin up and the LEDs look normal.

3) Check for obvious slot issues
- Inspect each IOX 9 PCIe slot for bent pins, debris, or damage.
- Ensure cards are fully seated and locking mechanisms engaged.

4) Remove all I/O cards from IOX 9 and retest
- Power down or offline the IOX shelf per HPE procedures (to avoid hot-plug impact on the management bus).
- Remove all PCIe cards from IOX 9.
- Power up IOX 9 and check if “I2C Buses” changes from Failed to OK.
- If I2C now reports OK with no cards installed: add cards back one at a time (or in small batches), checking the I2C status after each addition to identify the offending card/slot.
- If I2C still reports Failed with all cards removed: the replacement IOX shelf itself may have a backplane or management FRU issue. Proceed to step 7 and contact HPE.

5) Verify firmware baselines
- Ensure the complex firmware bundle (system/Onboard Administrator/Xfabric/IOX) is at a supported and consistent level.
- Check each I/O card’s firmware and option ROM versions against the Superdome 2 supported matrix for your exact model and OS. Update any cards that are behind. Even though “Firmware Mismatch: OK” is shown for the shelf, individual adapter firmware mismatches can still cause I2C issues.

6) Identify the culprit card
- When the I2C fails after reinserting cards, the last card/slot you reintroduced is the likely culprit. Swap that card into a different known-good slot or a different IOX to confirm the fault follows the card.
- If the fault stays with the slot, inspect that slot for damage and consider the IOX backplane as a suspect.

7) Collect logs and engage HPE if needed
- From the OA/complex manager, collect a full support/diag bundle (OA logs, hardware inventory, event logs). On Superdome 2, HPE may ask for an “sx3000/complex” log pack and IOX logs.
- Note the exact IOX 9 FRU part numbers and firmware, plus the list of cards/slots and their firmware versions.
- Open a case with HPE if:
- I2C still fails with all cards removed, or
- The issue follows the replacement shelf, or
- You identify a specific card model repeatedly causing I2C failures even with current firmware.

Regards,
Rakshitha K

Query: Superdome2 16 server I2C busses error

support_s — Tue, 12 May 2026 07:20:20 GMT

Hello,

Let us know if you were able to resolve the issue.

If you are satisfied with the answers then kindly click the "Accept As Solution" button for the most helpful response so that it is beneficial to all community members.

Please click on "Thumbs Up/Kudo" icon to give a "Kudo".

topic Query: Superdome2 16 server I2C busses error in Integrity Servers

Superdome2 16 server I2C busses error

Re: Superdome2 16 server I2C busses error

Re: Superdome2 16 server I2C busses error

Query: Superdome2 16 server I2C busses error