I'm running xubuntu Xenial, which has recently stopped booting correctly. H/W is an Intel NUC, boot disk is an M.2 SSD with 4 partitions:
Device Start End Sectors Size Type
/dev/sdb1 2048 1050623 1048576 512M EFI System
/dev/sdb2 1050624 42993663 41943040 20G Linux filesystem
/dev/sdb3 495923200 500117503 4194304 2G Linux swap
/dev/sdb4 42993664 495923199 452929536 216G Linux filesystem
(There is an additional SATA disk which is sda) All packages are up to date, kernel:
Linux sam 4.4.0-31-generic #50-Ubuntu SMP Wed Jul 13 00:07:12 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
It seems ubuntu is now running systemd by default. If I boot by selecting the 'upstart' version in the advanced options grub menu, the system comes up correctly with all partitions mounted as expected.
However when booting the default (systemd) version, the boot process hangs for a while before switching to emergency mode, displaying the message:
device-mapper: table: 252:1: multipath: error getting device
iwlwifi 0000:02:00.0: Unsupported splx structure
I think the first line relates to sdb, the second may be a red herring. dmesg gives a little additional info:
[ 1.402062] sd 3:0:0:0: [sdb] 500118192 512-byte logical blocks: (256 GB/238 GiB)
[ 1.402110] sd 3:0:0:0: [sdb] Write Protect is off
[ 1.402113] sd 3:0:0:0: [sdb] Mode Sense: 00 3a 00 00
[ 1.402115] sd 3:0:0:0: Attached scsi generic sg1 type 0
[ 1.402130] sd 3:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 1.403377] sdb: sdb1 sdb2 sdb3 sdb4
[ 1.403672] sd 3:0:0:0: [sdb] Attached SCSI disk
[ 2.206562] systemd[1]: systemd 229 running in system mode. (+PAM +AUDIT +SELINUX +IMA +APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ -LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD -IDN)
...
[ 2.344978] device-mapper: multipath: version 1.10.0 loaded
[ 2.345721] random: nonblocking pool is initialized
[ 2.378781] systemd[1]: Started Journal Service.
[ 2.402535] device-mapper: multipath round-robin: version 1.0.0 loaded
[ 2.403529] device-mapper: table: 252:1: multipath: error getting device
[ 2.403557] device-mapper: ioctl: error adding target to table
[ 2.513670] EXT4-fs (sdb2): re-mounted. Opts: errors=remount-ro
[ 2.536537] systemd-journald[952]: Received request to flush runtime journal from PID 1
At this point I see that /dev contains sdb and sdb2 and /dev/sdb2 is mounted (in rw, not ro), but sdb1, sdb3 & sdb4 are missing in /dev!
fdisk and gdisk correctly report these partitions.
mount -a expectedly fails due to missing devices.
Any thoughts are welcome!
Appending additional info requested by @heynnema:
fstab (UUIDs now commented since I tested with PARTUUIDs):
# /dev/sdb1
# LABEL=EFI /boot/efi vfat umask=0077 0 1
# UUID=1503-761C /boot/efi vfat umask=0077 0 1
PARTUUID=1c683c73-95ec-4de6-a98b-841650f2317c /boot/efi vfat umask=0077 0 1
# /dev/sdb2
# LABEL=xubuntu / ext4 errors=remount-ro,noatime 0 1
# UUID=c05b54a3-c2bf-4248-a020-1a6acddb99f6 / ext4 errors=remount-ro,noatime 0 1
PARTUUID=12fbd056-2e67-496e-b7d6-f5a097acaf12 / ext4 errors=remount-ro,noatime 0 1
# /dev/sdb3
# UUID=9ca249b6-b9da-4756-952e-4dbc13426527 none swap sw 0 0
PARTUUID=da8eb3c4-5d8b-45a9-b186-e114956ed69f none swap sw 0 0
# /dev/sdb4
# LABEL=Home /home ext4 defaults,noatime 0 2
# UUID=2d69cba0-ddb1-4746-a593-6d2811caf0a7 /home ext4 defaults,noatime 0 2
PARTUUID=548b1699-6832-4c0f-8fea-a053855e796d /home ext4 defaults,noatime 0 2
# HT-Data
# UUID=214a0d73-d36c-4ad6-8988-dbecdbc153f7 /media/HT-data ext4 defaults 0 1
PARTUUID=793ff092-6e09-4e22-b849-4d939c87ec46 /media/HT-data ext4 defaults 0 1
blkid (upstart):
/dev/sda1: LABEL="HT-Data" UUID="214a0d73-d36c-4ad6-8988-dbecdbc153f7" TYPE="ext3" PARTLABEL="home" PARTUUID="793ff092-6e09-4e22-b849-4d939c87ec46"
/dev/sdb1: LABEL="EFI" UUID="1503-761C" TYPE="vfat" PARTLABEL="EFI System Partition" PARTUUID="1c683c73-95ec-4de6-a98b-841650f2317c"
/dev/sdb2: LABEL="xubuntu" UUID="c05b54a3-c2bf-4248-a020-1a6acddb99f6" TYPE="ext4" PARTUUID="12fbd056-2e67-496e-b7d6-f5a097acaf12"
/dev/sdb3: UUID="9ca249b6-b9da-4756-952e-4dbc13426527" TYPE="swap" PARTUUID="da8eb3c4-5d8b-45a9-b186-e114956ed69f"
/dev/sdb4: LABEL="Home" UUID="2d69cba0-ddb1-4746-a593-6d2811caf0a7" TYPE="ext4" PARTUUID="548b1699-6832-4c0f-8fea-a053855e796d"
blkid (systemd):
/dev/sdb2: LABEL="xubuntu" UUID="c05b54a3-c2bf-4248-a020-1a6acddb99f6" TYPE="ext4" PARTUUID="12fbd056-2e67-496e-b7d6-f5a097acaf12"
/dev/mapper/SAMSUNG_HM500JI_S1WFJD0SC83565-part1: LABEL="HT-Data" UUID="214a0d73-d36c-4ad6-8988-dbecdbc153f7" SEC_TYPE="ext2" TYPE="ext3" PARTLABEL="home" PARTUUID="793ff092-6e09-4e22-b849-4d939c87ec46"
/dev/sda: PTUUID="2cddf033-6053-4295-96a2-b3fd22295c95" PTTYPE="gpt"
/dev/mapper/SAMSUNG_HM500JI_S1WFJD0SC83565: PTUUID="2cddf033-6053-4295-96a2-b3fd22295c95" PTTYPE="gpt"
Booting from USB, fsck returns 0 for each partition.
