[Cialug] Help with Understanding Drives

[Todd Walton]

Hey all,

I have a laptop with Ubuntu 16.04 on it that I know has one or more disks,
one or more of which might be SSD, and that the root and/or home partitions
are LUKS encrypted. I want to reinstall Linux on this laptop but I want to
save the user data on it, so I'm trying to figure out how to shuffle all
this around.

Using fdisk tells me there are two drives, "sda" and "nvme0n1". An lsblk
shows those two drives as well. I haven't seen "nvme" drives before, so I'm
not familiar with how Linux handles them.

Could the nvme drive be just the encrypted filesystem on top of the sda
partitions? How do I tell if those two are truly two different physical
disks or not? If the nvme is truly a separate physical disk, how could it
be that whoever set up this laptop wouldn't have used it at all? (I don't
see it being mapped to any filesystems.) The two have slightly different
sizes, so maybe they really are two physical disks. I don't know what's up
with all that "Microsoft" this-and-that. If it's a recovery drive that came
built into the laptop surely it wouldn't be 238 freakin' gigs.

===================================

@ ~> sudo fdisk -l

Disk /dev/nvme0n1: 238.5 GiB, 256060514304 bytes, 500118192 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: gpt
Disk identifier: F97E0C07-C73B-41D7-8CEC-57EDFB9C366C

Device             Start       End   Sectors   Size Type
/dev/nvme0n1p1      2048    534527    532480   260M EFI System
/dev/nvme0n1p2    534528    567295     32768    16M Microsoft reserved
/dev/nvme0n1p3    567296 498069503 497502208 237.2G Microsoft basic data
/dev/nvme0n1p4 498069504 500117503   2048000  1000M Windows recovery
environment

Disk /dev/sda: 232.9 GiB, 250059350016 bytes, 488397168 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: 0x522a56e1

Device     Boot   Start       End   Sectors   Size Id Type
/dev/sda1  *       2048    999423    997376   487M 83 Linux
/dev/sda2       1001470 468860927 467859458 223.1G  5 Extended
/dev/sda5       1001472 468860927 467859456 223.1G 83 Linux

Disk /dev/mapper/sda5_crypt: 223.1 GiB, 239541944320 bytes, 467855360
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

Disk /dev/mapper/ubuntu--vg-root: 215.6 GiB, 231487832064 bytes, 452124672
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

Disk /dev/mapper/ubuntu--vg-swap_1: 7.5 GiB, 8006926336 bytes, 15638528
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

===================================

@ ~> lsblk

NAME                    MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
sda                       8:0    0 232.9G  0 disk
├─sda5                    8:5    0 223.1G  0 part
│ └─sda5_crypt          253:0    0 223.1G  0 crypt
│   ├─ubuntu--vg-root   253:1    0 215.6G  0 lvm   /
│   └─ubuntu--vg-swap_1 253:2    0   7.5G  0 lvm   [SWAP]
└─sda1                    8:1    0   487M  0 part  /boot
nvme0n1                 259:0    0 238.5G  0 disk
├─nvme0n1p3             259:7    0 237.2G  0 part
├─nvme0n1p1             259:5    0   260M  0 part
├─nvme0n1p4             259:8    0  1000M  0 part
└─nvme0n1p2             259:6    0    16M  0 part

===================================

Help?

--
Todd