AIX Support have shared some tools they use for investigating this type of problem.
Install the devscan tool from there and use it to probe the SAN through the adapter.
Original Message:
Sent: Fri November 21, 2025 02:13 AM
From: Vivek M
Subject: LPAR Disk Path Issue- Disk Showing Only 6 Paths Instead of 8
I checked Mapping is available at vios side .
Best Regards,
Vivek M
IBM INDIA PVT LTD
Email :- vivek.m1@ibm.com
Ph No :- +91 7095361012

Original Message:
Sent: 11/20/2025 11:02:00 AM
From: Richard Westerik
Subject: RE: LPAR Disk Path Issue- Disk Showing Only 6 Paths Instead of 8
If the "cfgmgr" command on the AIX partition does not bring back the fscsi devices and doesn't add paths to "lspath" or "lsmpio, you can check the Virtual I/O Server(s).
Login as padmin and execute the following command:
lsmap -all -npiv
It will lists all mappings from the physical fcs port on the VIO server to the corresponding (virtual) fcs port on the AIX partition. The vfcmap can restore mapping that are missing.
If all mappings appear valid, physical cabling from VIOS to SAN switch, zoning & mapping should be checked.
------------------------------
Richard Westerik
Principal specialist
Simac IT NL bv
Ede
+31651575123
Original Message:
Sent: Thu November 20, 2025 04:51 AM
From: Vivek M
Subject: LPAR Disk Path Issue- Disk Showing Only 6 Paths Instead of 8
#lsdev -Ccadapter | grep -i fcs
fcs0 Available C2-T0 Virtual Fibre Channel Client Adapter
fcs1 Available C4-T0 Virtual Fibre Channel Client Adapter
fcs2 Available C5-T0 Virtual Fibre Channel Client Adapter
fcs3 Available C6-T0 Virtual Fibre Channel Client Adapter
fcs4 Available C7-T0 Virtual Fibre Channel Client Adapter
fcs5 Available C8-T0 Virtual Fibre Channel Client Adapter
#errpt -aj 26623394 | more
---------------------------------------------------------------------------
LABEL: FCP_ERR12
IDENTIFIER: 26623394
Date/Time: Fri Oct 10 12:04:54 IST 2025
Sequence Number: 1492
Machine Id: 00FC025A4B00
Node Id: drpbgbrpsrv
Class: H
Type: TEMP
WPAR: Global
Resource Name: fscsi2
Resource Class: driver
Resource Type: emfscsi
Location:
Description
COMMUNICATION PROTOCOL ERROR
Recommended Actions
PERFORM PROBLEM DETERMINATION PROCEDURES
Detail Data
SENSE DATA
0000 0020 0000 00AC 0000 0902 0202 0401 C050 760C 712C 00FA 0000 0000 0014 020D
0000 0000 0000 0AEA 0000 0000 0000 03EC 0000 0000 0000 0201 0600 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
5005 0768 1316 4E4E 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0015 0001 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0018 0100 0000 FC02 0000 0121 0001 0000 0000 5005 0768 1316 4E4E 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
------------------------------
Vivek M
Original Message:
Sent: Thu November 20, 2025 03:14 AM
From: Anas AlSaleh
Subject: LPAR Disk Path Issue- Disk Showing Only 6 Paths Instead of 8
HI
from the output all the fscsi0 , fscsi1 and fscsi3 are up except the fscsi2 reported error on error report ( 26623394 1010120425 T H fscsi2 COMMUNICATION PROTOCOL ERROR).
can you please share the output from below command , i need to see the status of FCS adapters from LPAR it self
# lsdev -Ccadapter | grep -i fcs
thank you
------------------------------
Anas AlSaleh
IBM Power Systems Software Specialist
Saudi Business Machines ( SBM )
Riyadh
Original Message:
Sent: Thu November 20, 2025 02:21 AM
From: Vivek M
Subject: LPAR Disk Path Issue- Disk Showing Only 6 Paths Instead of 8
Dear ,
All commands output file attached. Kindly review it
------------------------------
Vivek M
Original Message:
Sent: Sat November 15, 2025 10:58 PM
From: Anas AlSaleh
Subject: LPAR Disk Path Issue- Disk Showing Only 6 Paths Instead of 8
hi ,
what is the output from below commands please
- # lsmpio
- # lsmpio -ar
- # lsmpio -are
- # errpt
Thanks
------------------------------
Anas AlSaleh
IBM Power Systems Software Specialist
Saudi Business Machines ( SBM )
Riyadh
Original Message:
Sent: Fri November 14, 2025 05:28 AM
From: Vivek M
Subject: LPAR Disk Path Issue- Disk Showing Only 6 Paths Instead of 8
Hi all,
In my LPAR configuration, the disk should have 8 paths from 4 FCS adapters, but unfortunately, 2 paths from one FC adapter *(fcs2) are missing. Now it is showing only 6 paths. I checked, and all FCS adapters are in an available state. Please help me resolve this issue.
#lspath -l hdisk1
Enabled hdisk1 fscsi0
Enabled hdisk1 fscsi0
Enabled hdisk1 fscsi1
Enabled hdisk1 fscsi1
Enabled hdisk1 fscsi3
Enabled hdisk1 fscsi3
x Disk-Adapter-I/O qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqx
xName %busy read write xfers Disks Adapter-Type x
xvscsi2 0.0 0.0 0.0 KB/s 0.0 1 Virtual SCSI Client A x
xfcs3 0.0 32.0 16.0 KB/s 3.0 22 Virtual Fibre Channel x
xfcs0 0.0 40.0 16.0 KB/s 3.5 22 Virtual Fibre Channel x
xfcs1 0.0 56.0 0.0 KB/s 3.5 22 Virtual Fibre Channel x
xTOTALS 4 adapters 128.0 32.0 KB/s 10.0 23 TOTAL(MB/s)=0.2
------------------------------
Vivek M
------------------------------