Pillar Axiom 300 Storage System
 

PLA-Support>Sun Systems>DISK>Pillar Axiom>SN-DK: Ax300
 

In this Document

Goal

Fix

Applies to:

Goal

This article only applies to AX300 systems where there are two separate sources of AC Power. This article does not apply to the Ax500 or Ax600 or other Axiom models with redundant Slammer Power Supplies.

Fix

Hardware    Software
AX300        N/A

The rewiring should be done with the Axiom placed in
Shutdown, to avoid triggering a reset of the Slammer CUs.

Details

If there are two independent sources of AC power to an Ax300, loss of one of those sources will power off one Pilot CU and one Slammer CU. This leaves one surviving Pilot CU and Slammer CU, which should provide continuing data access as long as the external fabric and hosts are configured correctly. The surviving Slammer CU may go offline shortly after the power is lost.

The Ax300 Installation Guide has an error in the AC wiring for the Pilots for situations where there are two separate AC power sources available.

If one AC source fails, the surviving Pilot CU and Slammer CU do not have an ethernet connection, since the connection is through a Pilot CU or Slammer CU that has no power.

The surviving Slammer CU will detect that it is not receiving any heartbeats or heartbeat responses on the Private Management Network, the PMI and also does not see another Slammer CU on the Private Interconnect fabric, the PI. The CU will reset itself, in an attempt to re-establish communication with either its buddy Slammer CU or a Pilot CU.

FIX

The Ax300 Installation Guide and Ax300 Wiring Diagram will be modified to indicate this change.

The AC wiring to the Pilot CUs should be changed such that the top Pilot CU and the top Slammer CU have the same AC Power source. The bottom Pilot CU and the bottom Slammer CU should be changed to have the same AC Power source. This ensures that there is a PMI ethernet connection from the surviving pilot to the surviving Slammer CU.

The fix requires a maintenance period, since the Axiom should be shutdown for safety.

Place the Axiom in Shutdown

Trace the AC power to the Slammers and Pilot CUs.

Wire the AC to the top Pilot CU so it comes from the same PDU or external AC source as the top Slammer CU

Wire the AC to the bottom Pilot CU so it comes from the same PDU or external AC source as the bottom Slammer CU

Make sure both Pilot CUs are powered on. Some models have an power switch next to the AC cord. Others have a BIOS that turns on DC power when AC is supplied.

NOTE: check the DC indicator on the front panel of the Pilot CU. There are LEDs on the back of the Pilot that may be on when DC power is not.

Restart the Axiom and check that all components boot to Green and Normal status.

The information in the figure below will replace the current wiring in the Pillar Axiom 300 Advanced Hardware Installation Guide Table 40: Sample power cabling scheme with 230V power

Revised AC Power Wiring Diagram

The only cables shown are AC power and the PMI Ethernet. The top Pilot CU has a direct PMI ethernet connection to the top Slammer CU (green line), and the bottom Pilot CU has a direct PMI ethernet connection to the bottom CU (violet line). The revised wiring where the top Pilot and Slammer CU share AC power source (blue lines) and the bottom Pilot and Slammer CU share AC Power (red lines) ensures that there is at least one other CU node on the PMI.

This solution has no attachment