Expand Disk LXD VM

Centos

Existing size is about 10G on Centos host called nas

lxc config device set nas root size=100GiB
lxc shell nas

Add tools and expand (you can use fdisk/parted but this is easer)

lsblk
df -h

yum install e2fsprogs cloud-utils-growpart gdisk
growpart /dev/sda 2
resize2fs /dev/sda2

lsblk
df -h

Ubuntu

Ubuntu Script example (replace overide with set for existing)

set -e

readonly VM="myhost"
readonly CPU="8"
readonly MEM="4GB"
readonly DSK="60GB"

lxc init images:ubuntu/focal ${VM} -p default -p vm --vm
lxc config set ${VM} limits.cpu ${CPU}
lxc config set ${VM} limits.memory ${MEM}
lxc config device override ${VM} root size=${DISK}
lxc start ${VM}

sleep 10  # `lxc start` needs a `--wait`.

lxc exec ${VM} -- apt update
lxc exec ${VM} -- apt install cloud-initramfs-growroot -y
lxc exec ${VM} -- growpart /dev/sda 2
lxc exec ${VM} -- resize2fs /dev/sda2

Profile As well if you want

config:
  user.user-data: |
    apt_mirror: http://us.archive.ubuntu.com/ubuntu/
    ssh_pwauth: yes
    users:
      - name: ubuntu
        passwd: "\$6\$s.wXDkoGmU5md\$d.vxMQSvtcs1I7wUG4SLgUhmarY7BR.5lusJq1D9U9EnHK2LJx18x90ipsg0g3Jcomfp0EoGAZYfgvT22qGFl/"
        lock_passwd: false
        groups: lxd
        shell: /bin/bash
        sudo: ALL=(ALL) NOPASSWD:ALL
    growpart:
      mode: auto
      devices:
        - '/'
        - '/dev/sda'
        - '/dev/sda2'
      ignore_growroot_disabled: false
description: VN profile
devices:
  config:
    source: cloud-init:config
    type: disk
  eth0:
    nictype: bridged
    parent: lxdbr0
    type: nic
  root:
    path: /
    pool: default
    size: 100GB
    type: disk
name: vm