[GTALUG] Thinkpad [3]: Aligning size of dm-crypt and partition/filesystem

[o1bigtenor]

On Wed, Jun 15, 2016 at 9:43 AM, Matt Price via talk <talk at gtalug.org> wrote:
> Final question! In order to enable suspend to disk, I ended up shrinking my
> root partition (I also added an M.2 SSD, so the whole thing was a bit
> complex). In the end I got it to work, but I made some kind of an error and
> currently my on-disk “crypt” is a little larger than the partition and file
> system that I am using for root, so I have some wasted space on the disk:
>
> ➜  ~ sudo fdisk /dev/sda
>
> Command (m for help): p
> Disk /dev/sda: 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: 9B4C2E92-6C7D-4C69-B67B-1823E4DB9BA6
>
> Device         Start       End   Sectors   Size Type
> /dev/sda1       2048   1026047   1024000   500M EFI System
> /dev/sda2    1026048 106907647 105881600  50.5G Linux filesystem
> /dev/sda3  106907648 483340287 376432640 179.5G Linux LVM
> /dev/sda4  483340288 500117503  16777216     8G Linux swap
>
> ➜  ~ sudo cryptsetup status cryptsetup
> /dev/mapper/cryptsetup is active and is in use.
>   type:    LUKS1
>   cipher:  aes-xts-plain64
>   keysize: 256 bits
>   device:  /dev/sda2
>   offset:  4096 sectors
>   size:    105877504 sectors
>   mode:    read/write
>
> Anyone out there have advice abot how to safely and reliably expand the
> partition and the file system so that they both end precisely where the
> crypt does?
>
> Thanks again guys! as always, it’s much appreciated.
>

No ideas on the other two problems but on this one I would recommend
using something like:

boot your system using a system rescue disc
adjust your partition(s)  (carefully please) using gparted
close

reboot as regular

Should be real easy (assuming that the empty space is right beside
where you want it.
Recommend a backup before but then you already know that - - yes?

Let us know what you use