Fault LED is lit for no apparent reason on a FAS or AFF HA storage system with internal-only SAS storage

Applies to

• Platforms:
  • AFF A220, AFF A200, AFF A150, AFF C190, ASA A150
  • FAS2820, FAS2750, FAS2720, FAS2650, FAS2620, FAS2554, FAS2552, FAS2520
• High-availability configuration (2 processor control modules (PCM) are inserted in the chassis and are configured for HA operation)
• Internal SAS storage only (no external SAS storage shelves are attached)
• 0a or 0b SAS ports on the PCMs are directly connected to the SAS ports on the other PCM

Issue

This article applies if any of the following symptoms are observed.

1. EMS event: When port 0b on PCM A is connected directly to port 0b on PCM B, you will occasionally see this EMS event in the event log: config.invalid.PortToPort

Fri Dec 09 14:30:00 PST [node1: pmcsas_intrd_0: config.invalid.PortToPort:error]: SAS adapter "0b" is attached to another SAS adapter.

2. Environment: Run the environment shelf nodeshell command from one of the nodes. The listed SAS cable serial number on the internal shelf's [2] and [4] SAS expander ports are identical. Expander port [2]  is the 0a port on PCM A and port [4] is the 0a port on PCM B. 

      SAS cable information by element:
      [1] Internal connector
      [2] Vendor: Amphenol
      Type: QSFP passive copper 0.5-1.0m  ID: 01 Swaps: 0
      Serial number: APF14131767EE1  Part number: 112-00176+A0
      [3] Internal connector
      [4] Vendor: Amphenol
      Type: QSFP passive copper 0.5-1.0m  ID: 00 Swaps: 0
      Serial number: APF14131767EE1  Part number: 112-00176+A0 

3. sysconfig -a: Run the sysconfig -a nodeshell command from both nodes. The following conditions are observed:

• System Storage Configuration: Single-Path HA
• The SAS 0b ports on both nodes show the identical QSFP serial number.

 

                slot 0: SAS Host Adapter 0b (PMC-Sierra PM8001 rev. C, SAS, <UP>)
                                Firmware rev:       01.11.06.00
                                Base WWN:           5:00a098:00361ff:74
                                Phy State:          [4] Enabled, 6.0 Gb/s
                                                    [5] Enabled, 6.0 Gb/s
                                                    [6] Enabled, 6.0 Gb/s
                                                    [7] Enabled, 6.0 Gb/s
                                QSFP Vendor:        Amphenol        
                                QSFP Part Number:   112-00176+A0    
                                QSFP Type:          Passive Copper 0.5m ID:01
                                QSFP Serial Number: APF14131767EDC

                slot 0: SAS Host Adapter 0b (PMC-Sierra PM8001 rev. C, SAS, <UP>)
                                Firmware rev:       01.11.06.00
                                Base WWN:           5:00a098:0035e3d:b4
                                Phy State:          [4] Enabled, 6.0 Gb/s
                                                    [5] Enabled, 6.0 Gb/s
                                                    [6] Enabled, 6.0 Gb/s
                                                    [7] Enabled, 6.0 Gb/s
                                QSFP Vendor:        Amphenol        
                                QSFP Part Number:   112-00176+A0    
                                QSFP Type:          Passive Copper 0.5m ID:00
                                QSFP Serial Number: APF14131767EDC

 

4. SAS-Expander-Map: Run the sasstat expander_map nodeshell command from one of the nodes. The output contains only one entry on channel 0a.

Expanders on channel 0a: 
Level  1: WWN 500a098003xxxxxx, ID  0, Serial Number ' SHFFG1416xxxxxx', Product 'DS212IOM6E      ', Rev '0142', Slot A

Expanders on channel 0b: