Public bug reported: Successfully upgraded to vivid. During an update to the kernel the system regenerated the grub menu which ignored the root partition on my SSD.
Output from parted -l Model: ATA OCZ-AGILITY3 (scsi) Disk /dev/sda: 60.0GB Sector size (logical/physical): 512B/512B Partition Table: msdos Disk Flags: Number Start End Size Type File system Flags 1 1049kB 368MB 367MB primary ntfs boot 2 369MB 60.0GB 59.7GB extended 5 369MB 60.0GB 59.7GB logical ext4 Model: ATA WDC WD15EADS-00R (scsi) Disk /dev/sdb: 1500GB Sector size (logical/physical): 512B/512B Partition Table: msdos Disk Flags: Number Start End Size Type File system Flags 1 32.3kB 632GB 632GB primary ntfs 4 632GB 1496GB 864GB primary ext4 3 1496GB 1500GB 4721MB primary linux-swap(v1) update-grub correctly identifies the partitions on: sdb1 sdb4 It ignores the partition on sda5 Thus the default kubuntu which boots is the one on sdb4 which is an older copy of kubuntu 13.10 rather than the later 15.04 on sda5. Interestingly running update-grub on the old copy of Kubuntu correctly generates a grub.cfg with an entry for sda5. For this reason I believe this is a late change to the grub code base which is causing this defect. This is a section of dmesg relating to the drives. dmesg | grep sd [ 19.434247] sd 2:0:0:0: [sda] 117231408 512-byte logical blocks: (60.0 GB/55.8 GiB) [ 19.434287] sd 2:0:0:0: [sda] Write Protect is off [ 19.434290] sd 2:0:0:0: [sda] Mode Sense: 00 3a 00 00 [ 19.434302] sd 2:0:0:0: Attached scsi generic sg0 type 0 [ 19.434303] sd 2:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 19.434632] sd 3:0:0:0: [sdb] 2930275055 512-byte logical blocks: (1.50 TB/1.36 TiB) [ 19.434665] sd 3:0:0:0: Attached scsi generic sg1 type 0 [ 19.434702] sd 3:0:0:0: [sdb] Write Protect is off [ 19.434705] sd 3:0:0:0: [sdb] Mode Sense: 00 3a 00 00 [ 19.434736] sd 3:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 19.434877] sda: sda1 sda2 < sda5 > [ 19.435134] sd 2:0:0:0: [sda] Attached SCSI disk [ 19.480834] sdb: sdb1 sdb3 sdb4 [ 19.481269] sd 3:0:0:0: [sdb] Attached SCSI disk [ 20.906552] EXT4-fs (sda5): mounted filesystem with ordered data mode. Opts: (null) [ 21.872733] Adding 4610648k swap on /dev/sdb3. Priority:-1 extents:1 across:4610648k FS [ 22.096519] EXT4-fs (sda5): re-mounted. Opts: errors=remount-ro [ 22.270531] EXT4-fs (sdb4): mounted filesystem with ordered data mode. Opts: (null) The sda drive is a SSD and the sdb drive is a standard hard disk drive. Output from update-grub, note the missing sda5 entry. root@Office:/boot/grub# update-grub Generating grub configuration file ... Found linux image: /boot/vmlinuz-3.19.0-26-generic Found initrd image: /boot/initrd.img-3.19.0-26-generic Found linux image: /boot/vmlinuz-3.19.0-25-generic Found initrd image: /boot/initrd.img-3.19.0-25-generic Found memtest86+ image: /boot/memtest86+.elf Found memtest86+ image: /boot/memtest86+.bin Found Windows 8 (loader) on /dev/sda1 Found Microsoft Windows XP Professional on /dev/sdb1 Found Ubuntu 13.10 (13.10) on /dev/sdb4 done ProblemType: Bug DistroRelease: Ubuntu 15.04 Package: grub-pc 2.02~beta2-22ubuntu1.1 ProcVersionSignature: Ubuntu 3.19.0-26.28-generic 3.19.8-ckt4 Uname: Linux 3.19.0-26-generic x86_64 NonfreeKernelModules: nvidia ApportVersion: 2.17.2-0ubuntu1.3 Architecture: amd64 CurrentDesktop: KDE Date: Wed Sep 9 13:07:04 2015 InstallationDate: Installed on 2014-03-23 (534 days ago) InstallationMedia: Kubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1) SourcePackage: grub2 UpgradeStatus: Upgraded to vivid on 2015-08-10 (29 days ago) ** Affects: grub2 (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug vivid ** Attachment added: "Faulty grub.cfg file." https://bugs.launchpad.net/bugs/1493615/+attachment/4459513/+files/grub.cfg -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1493615 Title: update-grub ignores linux partition To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1493615/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs