Ttyjfyk

I have a laptop with Arch on it, and I sized the root partition too small. Now I want to expand the partition by taking some from the home partition. I will put the details of the specifics below. My question(s) to you is

1) Am I just expanding the root? Or shrinking the home? Or is it both? If both then does order matter? I see several online tuts that sort of do them different ways. So it's confusing to me.

2) Should I follow the arch documentation exactly? It's not like other tuts I've seen which may not be distro specific. Also asking because it mentions things like make a new partition under expand, but never says anything about what to do with the old one. It would be great if you could explain this if the answer is yes.

3) Do I need to update my fstab afterwards?

4) If all goes well, I should still have my data on these partitions right? Obviously I'm backing up just to be sure.

Here are my specific details:

> df -h
Filesystem Size Used Avail Use% Mounted on
dev 7.7G 0 7.7G 0% /dev
run 7.7G 1.2M 7.7G 1% /run
/dev/mapper/archvg-root 9.8G 9.3G 0 100% /
tmpfs 7.7G 723M 7.0G 10% /dev/shm
tmpfs 7.7G 0 7.7G 0% /sys/fs/cgroup
tmpfs 7.7G 16K 7.7G 1% /tmp
/dev/nvme0n1p1 749M 62M 688M 9% /boot
/dev/mapper/archvg-home 456G 3.0G 430G 1% /home
tmpfs 1.6G 16K 1.6G 1% /run/user/1000
/dev/fuse 250G 78M 250G 1% /run/user/1000/keybase/kbfs

> lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
nvme0n1 259:0 0 477G 0 disk
├─nvme0n1p1 259:1 0 750M 0 part /boot
└─nvme0n1p2 259:2 0 476.2G 0 part
 └─archlv 254:0 0 476.2G 0 crypt
 ├─archvg-swap 254:1 0 2G 0 lvm [SWAP]
 ├─archvg-root 254:2 0 10G 0 lvm /
 └─archvg-home 254:3 0 464.2G 0 lvm /home

> sudo pvdisplay -m
 --- Physical volume ---
 PV Name /dev/mapper/archlv
 VG Name archvg
 PV Size 476.20 GiB / not usable <1.32 MiB
 Allocatable yes (but full)
 PE Size 4.00 MiB
 Total PE 121908
 Free PE 0
 Allocated PE 121908
 PV UUID m11dPA-mPYo-6dLS-mXPF-V1Ww-jXuO-QXfB8e

 --- Physical Segments ---
 Physical extent 0 to 511:
 Logical volume /dev/archvg/swap
 Logical extents 0 to 511
 Physical extent 512 to 3071:
 Logical volume /dev/archvg/root
 Logical extents 0 to 2559
 Physical extent 3072 to 121907:
 Logical volume /dev/archvg/home
Logical extents 0 to 118835

Here is the steps I plan on taking

Boot from a live USB

# Step 1: Clone the current partition to a new partition
> dd if=/dev/mapper/archvg-root of=/dev/mapper/archvg2-root bs=4M

# Step 2: Extend the new partition
> cryptsetup open /dev/mapper/archvg2-root archlv

# Step 3: Enlarge the PV to use all the available remaining space of the partition
> pvresize /dev/mapper/archlv

## Review
> pvdisplay -m

# Step 4: Resize /home Logical Volume (trying to make it 100G)
> lvresize -L +90.2G /dev/CryptVolumeGroup/root

## Review
> pvdisplay -m

# Step 5: Resize encrypted volume (Trying to give it some space)
> resize2fs -p /dev/CryptVolumeGroup/root 101G

# Reboot

Here are other references of other's doing this differently which I'm still looking into if they have better methods or not.

• 
  https://serverfault.com/questions/394902/resizing-a-luks-encrypted-volume (He's unmounting, not mentioned in Arch docs. Not sure I need to)


• Extend a LUKS encrypted partition to fill disk


• 
  https://blog.tinned-software.net/increase-the-size-of-a-luks-encrypted-partition/ (seems like less steps)

If more detailed information about the specifics is helpful, please let me know and I'll update this with them.