Ubuntu "live" Server 20.04 - How to create custom partition /boot + LVM on a single disk?

Question

This is what I want to accomplish and I have to use the "legacy" image to do this but Canonical is phasing out the Debian installer in favor of their "live" installer so I need to get this figured out. Here is what I am trying to create:

/boot - 1G, ext4

LVG volume group
- /root - 4G, ext4
- /var - 2G, ext4
- /home - 1G, ext4
- /tmp - 1G, ext4
- /bak - 1G, ext4

The problem is that I have a single 30 GB drive (Virtual Disk) and the storage configuration screen looks like this:

To continue you need to: Mount a filesystem at / and Select a boot disk
FILE SYSTEM SUMMARY
  No disks or partitions mounted.
AVAILABLE DEVICES
[ VBOX_HARDDISK_abc123, local disk, 30G ]
[ Create volume group (LVM) ]
USED DEVICES
  No used devices

If I select the "local disk" and choose "Use As Boot Device" then my option to create a volume group (LVM) or RAID goes away.

If I select "Create volume group," then the option is to use the entire disk which then removes the option to "select a boot disk" to continue. I can create a /boot inside the LVM but that is NOT where I want it to reside AND you cannot select it to actually boot from that anyway.

I could add a 1GB disk because it is a virtual machine but I am thinking about the process for a physical machine as well that only "presents" a single disk for the OS to use.

This is the guide with detailed steps I maintain for my base server rollout for 18.04 that I am trying to update for 20.04 - https://hammondslegacy.com/forum/viewtopic.php?f=40&t=244

Solution

Alright, I assume that you tried to format and/or mount the 3rd (root) partition. You have to leave it unformatted and unmounted, this way the option for LVM remains.

NOTE: When you create the Logical Volumes inside of your Volume Group make sure to format and mount them, otherwise the installer will fail.

At the Storage Configuration step, move to AVAILABLE DEVICES and make the following changes:

1. Create EFI or BIOS partition; select Use As Boot Device.
2. Create boot partition; select Add GPT Partition, set the size, format as ext4 and mount at /boot.
3. Create root partition; select Add GPT Partition, leave size empty (uses remaining disk space), do NOT format and do NOT mount (leave unformatted/leave unmounted).
4. Create Volume Group; select Create volume group (LVM), name it and select partition 3 with the checkbox.
5. Create Logical Volume(s); Move to the newly created Volume Group, select Create Logical Volume, name it, set size (blank for remaining disk space), format it and mount it.
6. Repeat step 5 for all the Logical Volumes you want to create.

Hope this helps.

Comments

[ford04]

upvoted, works.

[pepoluan]

you're a savior!! thanks!!!