In an Azure environment, exporting a disk for Flexible Storage Sharing (FSS) may fail with "Disk not supported for FSS operation" error

Last published : Jun 10, 2026
For Flexible Storage Sharing, you must first export all the non-shared disks for network sharing. If your deployment setup involves JBOD type of disks, you may notice the following while exporting the non-shared disks:
  • The disk export operation fails with the "Disk not supported for FSS operation" error
# vxdisk export DiskName

VxVM vxdisk ERROR V-5-1-531 Device DiskName : export failed: Disk not supported for FSS operations

  • The checkfss disk command fails with the "Disk not valid for FSS operation" error
# vxddladm checkfss DiskName

VxVM vxddladm INFO V-5-1-18714 DiskName is not a valid disk for FSS operation

This issue occurs if a JBOD definition is not added to the disks.
Workaround:
Before exporting a disk for network sharing, add a JBOD definition on the disk.
Note: You can add a JBOD definition to a disk only if the disk SCSI inquiry supports a unique serial number. You cannot export a disk for network sharing, if the disk's SCSI inquiry fails to have a unique serial number.
To add a JBOD definition to a disk, perform the following steps:
  1. Run a query on the standard disk pages (0, 0x80, and 0x83) to find the available unique serial number.
For page 0:
# /etc/vx/diag.d/vxscsiinq -d /dev/vx/rdmp/DiskName
For page 0x80:
# /etc/vx/diag.d/vxscsiinq -d -e 1 -p 0x80 /dev/vx/rdmp/DiskName
For page 0x83
# /etc/vx/diag.d/vxscsiinq -d -e 1 -p 0x83 /dev/vx/rdmp/DiskName
Following is a sample output of the command for page number 0x83 that contains the unique serial number.
------- Identifier Descriptor 1 -------
ID type             : 0x1 (T10 vendor ID based)
Protocol Identifier : 0x0
Code set            : 0x1
PIV                 : 0x0
Association         : 0x0
Length              : 0x18
Data                : 4d5346542020202069c0ae2f82ab294b834866ff...
        /dev/vx/rdmp/DiskName: Raw data size 32
Bytes:  0 -  7  0x00  0x83  0x00  0x1c  0x01  0x01  0x00  0x18 ........
Bytes:  8 - 15  0x4d  0x53  0x46  0x54  0x20  0x20  0x20  0x20 MSFT
Bytes: 16 - 23  0x69  0xc0  0xae  0x2f  0x82  0xab  0x29  0x4b i../..)K
Bytes: 24 - 31  0x83  0x48  0x66  0xff  0x1d  0xd3  0xf5  0xcb .Hf.....
  1. Note the following values from the command output in step 1:
opcode= 0x12 (18) (This is a standard opcode)
pagecode= page number that contains the unique serial number (for example, 083)
offset= byte offset where the serial number starts (For example, in the output here the offset value is 8)
length= length of the unique serial number that is provided in the Length field (24 or 0x18)
  1. Add JBOD definition.
# vxddladm addjbod vid=vendorid serialnum=opcode /pagecode /offset /length
For example, # vxddladm addjbod vid=MSFT serialnum=18/0x83/8/24
  1. Scan disks.

# vxdisk scandisks

  1. Verify if the JBOD definition has been added sucessfully.
# vxddladm checkfss DiskName
The command output displays a confirmation message.