I have two Ubuntu 18.04 installations on my machine:

  1. personal /dev/sda1
  2. work (full-disk encryption) /dev/sda3

I installed some updates on my personal partition last night (see log on pastebin: https://pastebin.com/9sv2epHK), and now the bootloader doesn't ask me which partition to boot. (It used to be that before anything graphical showed up, I had to enter a password to decrypt the disk. Only then would I be prompted for which OS to boot.)

Any idea how to fix this? (It's been so long since I set up the machine, that I don't have any fluency in this area.)


Both installataions have the following /etc/lsb-release:


fdisk -l /dev/sda gives the following:

Disk /dev/sda: 119.2 GiB, 128035676160 bytes, 250069680 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x0002928e

Device     Boot     Start       End   Sectors  Size Id Type
/dev/sda1  *         2048 132708952 132706905 63.3G 83 Linux
/dev/sda2       176494590 250068991  73574402 35.1G  5 Extended
/dev/sda3       132710400 175677439  42967040 20.5G 83 Linux
/dev/sda5       225544192 250068991  24524800 11.7G 82 Linux swap / Solaris
/dev/sda6       201019392 225544191  24524800 11.7G 82 Linux swap / Solaris
/dev/sda7       176494592 201017343  24522752 11.7G 82 Linux swap / Solaris
  • Please edit your question and add more details. Which version of Ubuntu do you use? Show the output of cat /etc/lsb-release. Show the partition table. Assuming your hard disk is /dev/sda, show the output of sudo fdisk -l /dev/sda. Which software did you update? You can show the lines matching yesterday's date from /var/log/dpkg.log. – Bodo Dec 16 '19 at 14:58
  • @Bodo, thanks for the guidance! I've added the three items which you indicated. – JellicleCat Dec 16 '19 at 15:20

Well, it seems the updates updated my grub config.

To solve the problem, I decrypted and mounted the work partition, then copied my grub config from the work partition to the personal partition and ran update-grub:


This gives me two volume names: /dev/NAME/swap and /dev/NAME/VOL. I use these values in the commands below.

vgchange -ay # activate all of the volumes so that they can be mounted
cryptsetyp luksOpen /dev/sda3 NAME # this prompts for a password to decrypt the volume
mkdir /media/mydev
mount /dev/mapper/NAME-VOL /media/mydev # Notice that NAME and VOL are separated by a hypen instead of slash here
cp /media/mydev/etc/default/grub /etc/default/grub

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