** Summary changed: - Multipath JBOD storage devices are not shown via /dev/mapper but each path as a single device. + multipathd bcache disks do not get picked up by multipath-tools during boot
** Description changed: - As in the title, if machine has multipath storage device connected e.g. - JBOD via SAS controller, then each disk in the JBOD is reported N times, - depend how many paths you have. It's problematic when you do - commissioning as things are done multiple times, badblock test takes - forever as each disk is done multiple times and also configuring when - you do e.g. Ceph OSD deployment as you don't see a device you are going - to use, you have to first ssh into a system and check all /dev/mapper to - find a correct device for OSD. + [ Impact ] + + When using multipathd disks as bcache, multipath-tools does not pick the + disks up at boot time. + + [ Test Case ] + + 1) get an image + $ wget https://cdimage.ubuntu.com/ubuntu-server/daily-live/pending/noble-live-server-amd64.iso + + 2) Create bcache disk + $ fallocate -l 20G image.img + $ make-bcache -C image.img + + 3) Boot into iso with multipathed bcache disk + $ kvm -m 2048 -boot d -cdrom ./noble-live-server-amd64.iso -device virtio-scsi-pci,id=scsi -drive file=image.img,if=none,id=sda,format=raw,file.locking=off -device scsi-hd,drive=sda,serial=0001 -drive if=none,id=sdb,file=image.img,format=raw,file.locking=off -device scsi-hd,drive=sdb,serial=0001 + + Select "Try or install Ubuntu" wait for the OS to load. Press F2 to + escape to a shell to check multipathed devices. ** Description changed: [ Impact ] When using multipathd disks as bcache, multipath-tools does not pick the disks up at boot time. + + This is due to an interaction between bcache-tools and multipath-tools. + The udev rules for bcache-tools, specifically + /lib/udev/rules.d/69-bcache.rules occupies the disk during boot so + multipath-tools fails to interact with the disks. [ Test Case ] 1) get an image $ wget https://cdimage.ubuntu.com/ubuntu-server/daily-live/pending/noble-live-server-amd64.iso 2) Create bcache disk $ fallocate -l 20G image.img $ make-bcache -C image.img 3) Boot into iso with multipathed bcache disk $ kvm -m 2048 -boot d -cdrom ./noble-live-server-amd64.iso -device virtio-scsi-pci,id=scsi -drive file=image.img,if=none,id=sda,format=raw,file.locking=off -device scsi-hd,drive=sda,serial=0001 -drive if=none,id=sdb,file=image.img,format=raw,file.locking=off -device scsi-hd,drive=sdb,serial=0001 Select "Try or install Ubuntu" wait for the OS to load. Press F2 to escape to a shell to check multipathed devices. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1887558 Title: multipathd bcache disks do not get picked up by multipath-tools during boot To manage notifications about this bug go to: https://bugs.launchpad.net/bcache-tools/+bug/1887558/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
