Sentinel 8.2 Appliance in Hyper-V Server 2016 does not start after a reboot.

  • 7023143
  • 02-Jul-2018
  • 22-Jun-2020


Sentinel 8.2 


In Hyper-V Server 2016, Sentinel appliance does not start when you reboot it and displays the following message: 

You are in emergency mode. After logging in, type "journalctl xb" to view System logs, "systemctl reboot" to reboot, "systemctl default" or ^D to Try again to boot into default mode.


    Manually modify the disk UUID.

        1) After installing appliance (first boot), Login to root

        2) Verify /dev/disk/by-id entries for partitions are matching in /etc/fstab file.

            fstab partition IDs:


            CAF-HPV:~ # cat /etc/fstab

            /dev/disk/by-id/scsi-14d53465420202020f21b50e22267274c823e145500a372b7-part1 / ext3 acl 1 1

            /dev/disk/by-id/scsi-14d53465420202020f21b50e22267274c823e145500a372b7-part2 swap swap defaults 0 0

            Actual Partition IDs:


            CAF-HPV:~ # ls -l /dev/disk/by-id/*

            lrwxrwxrwx 1 root root   9 Jun 26 22:10 /dev/disk/by-id/ata-Virtual_CD -> ../../sr0

            -rw-r--r-- 1 root root 444 Jun 26 22:10 /dev/disk/by-id/scsi-14d53465420202020f21b50e22267274c823e145500a372b7

            lrwxrwxrwx 1 root root   9 Jun 26 22:24 /dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7 -> ../../sda

            lrwxrwxrwx 1 root root  10 Jun 26 22:24 /dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part1 -> ../../sda1

            lrwxrwxrwx 1 root root  10 Jun 26 22:24 /dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part2 -> ../../sda2

        3) Replace the actual partition IDs in the following files

            - /etc/fstab

            - /etc/default/grub

            - /boot/grub2/grub.cfg

            Examples as below:

            Changing partition IDs in fstab file


            /dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part1 / ext3 acl 1 1

            /dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part2 swap swap defaults 0 0

            Changing partition IDs in default grub file


            GRUB_CMDLINE_LINUX=" root=/dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part1 disk=/dev/disk/by-id/scsi-14d53465420202020811af9f56ec23a4197de0d20c3d787db resume=/dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part2 nomodeset quiet"

            Changing partition ID's in grub.cfg file


            linux   /boot/vmlinuz-4.4.131-94.29-default root=UUID=ace9acb3-ac2b-47f0-960d-5b7cd5b51b47  root=/dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part1 disk=/dev/disk/by-id/scsi-14d53465420202020 811af9f56ec23a4197de0d20c3d787db resume=/dev/disk/by-id/scsi-360022480f21b50e22267145500a372b7-part2 nomodeset quiet

        4) Reboot the VM

              It will detect the scsi partition ID's correctly and boot appliance normally.


This issue occurs because the operating system modifies the disk UUID during installation. Therefore, during reboot it cannot find the disk.