Public bug reported: 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. ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1622894 Title: sg devices are not being created for SCSI storage controller devices starting from v4.4.0-30 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1622894/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
