Most storage array expose a store controller device to logical unit 0.
Following LP #1567602, when this happens and the alua driver is loaded, Ubuntu doesn't create the sg device for it, and linux fails to discover the disks that are attached to higher logical unit numbers.
With kernel version 4.4.0-31, we tried a number of things:
- With a disk mapped to LUN0, everything is working.
- Without a disk mapped to LUN0, nothing works - linux doesn't see disks mapped to higher LUNs, calling rescan_scsi_bus throws a stack trace to syslog: https://gist.github.com/grzn/20c05ce3fc96062ec9572fd5b8093b55
- When turning on SCSI logging to the maximum (https://access.redhat.com/articles/337903 - 0xfffffff), we see that after ALUA driver rejected the SCSI controller nothing happens (look for 18:0:0:0 which is a controller here (https://gist.github.com/grzn/f8b65dd07b2df5f3f72ca8121d8c93ad) vs 19:0:00 which is a disk here (https://gist.github.com/grzn/48da86b7f7390dab2983927862cda949).
- When removing the scsi_dh_alua driver and then reloading the lpfc driver, everything is working as expected when no disk is mapped to LUN0.
---
AlsaDevices:
total 0
crw-rw---- 1 root audio 116, 1 Sep 12 18:00 seq
crw-rw---- 1 root audio 116, 33 Sep 12 18:00 timer
AplayDevices: Error: [Errno 2] No such file or directory
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1:
DistroRelease: Ubuntu 16.04
HibernationDevice: RESUME=UUID=1b089ce2-057f-44d6-9e53-5ee1b7fb5be9
IwConfig: Error: [Errno 2] No such file or directory
Lsusb: Error: command ['lsusb'] failed with exit code 1:
MachineType: VMware, Inc. VMware Virtual Platform
Package: linux (not installed)
PciMultimedia:
ProcFB: 0 svgadrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic root=UUID=6738fbd7-7243-4860-949f-717dfd084c43 ro quiet splash
ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13
RelatedPackageVersions:
linux-restricted-modules-4.4.0-31-generic N/A
linux-backports-modules-4.4.0-31-generic N/A
linux-firmware 1.157.3
RfKill: Error: [Errno 2] No such file or directory
Tags: xenial xenial
Uname: Linux 4.4.0-31-generic x86_64
UnreportableReason: The report belongs to a package that is not installed.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:
_MarkForUpload: False
dmi.bios.date: 09/17/2015
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: 6.00
dmi.board.name: 440BX Desktop Reference Platform
dmi.board.vendor: Intel Corporation
dmi.board.version: None
dmi.chassis.asset.tag: No Asset Tag
dmi.chassis.type: 1
dmi.chassis.vendor: No Enclosure
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvr6.00:bd09/17/2015:svnVMware,Inc.:pnVMwareVirtualPlatform:pvrNone:rvnIntelCorporation:rn440BXDesktopReferencePlatform:rvrNone:cvnNoEnclosure:ct1:cvrN/A:
dmi.product.name: VMware Virtual Platform
dmi.product.version: None
dmi.sys.vendor: VMware, Inc.
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1622894
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.