Ubuntu 16.04: Run containers with LXD/LXC

Install packages for LXD/LXC and ZFS with apt.

$ sudo apt install -y lxd lxd-client lxd-tools criu
$ sudo apt install -y zfsutils-linux
$ sudo modprobe zfs # or reboot machine

A criu package is for live migration. ZFS is used for containers store. ZFS should be used when there is a block device/volume for ZFS. If not using ZFS, a directory on filesystem is used.

Initialize LXD and lxd-bridge with interactive mode. "Address to bind LXD to" means which NIC is listened by LXD daemon.

$ sudo lxd init
Name of the storage backend to use (dir or zfs): zfs
Create a new ZFS pool (yes/no)? yes
Name of the new ZFS pool: tank
Would you like to use an existing block device (yes/no)? no
Size in GB of the new loop device (1GB minimum): 20
Would you like LXD to be available over the network (yes/no)? yes
Address to bind LXD to (not including port): 0.0.0.0
Port to bind LXD to (8443 recommended): 8443
Trust password for new clients:
Again:
Do you want to configure the LXD bridge (yes/no)? yes
Warning: Stopping lxd.service, but it can still be activated by:
  lxd.socket
LXD has been successfully configured.

Using –auto option can initialize LXD without interactive mode.

$ sudo lxd init --auto \
--storage-backend zfs \
--storage-pool tank \
--storage-create-loop 20 \
--network-address 0.0.0.0 \
--network-port 8443 \
--trust-password password

A case of dir is as below.

$sudo lxd init --auto \
     --storage-backend dir \
     --network-address 0.0.0.0 \
     --network-port 8443 \
     --trust-password password

lxd-bridge can be initialized without interactive mode.

$ sudo systemctl stop lxd-bridge
$ sudo systemctl --system daemon-reload
$ sudo su -c 'cat <<EOF > /etc/default/lxd-bridge
USE_LXD_BRIDGE="true"
LXD_BRIDGE="lxdbr0"
UPDATE_PROFILE="true"
LXD_CONFILE=""
LXD_DOMAIN="lxd"
LXD_IPV4_ADDR="10.202.80.1"
LXD_IPV4_NETMASK="255.255.255.0"
LXD_IPV4_NETWORK="10.202.80.1/24"
LXD_IPV4_DHCP_RANGE="10.202.80.2,10.202.80.254"
LXD_IPV4_DHCP_MAX="252"
LXD_IPV4_NAT="true"
LXD_IPV6_ADDR=""
LXD_IPV6_MASK=""
LXD_IPV6_NETWORK=""
LXD_IPV6_NAT="false"
LXD_IPV6_PROXY="false"
EOF
'
$ sudo systemctl enable lxd-bridge
$ sudo systemctl start lxd-bridge

Create containers with lxc launch. '.' and '_' cannot be used to containers name.

$ # lxc launch <image> <countainer>
$ lxc launch ubuntu:16.04 ubuntu-16-04

A image of Debian 8 in images.linuxcontainers.org is as below.

images:debian/jessie/amd64

You can get image list with below command.

$ lxc image list <remote>:

The remote servers are images, ubuntu and ubuntu-daily by default. Image size is about 100MByte.

$ lxc image list images:
$ lxc image list ubuntu:
$ lxc image list ubuntu-daily:

A default profile is used for containers network by default.

$ lxc profile list
default
docker
$ lxc profile show default
devices:
  eth0:
    name: eth0
    nictype: bridged
    parent: lxdbr0
    type: nic

Stop containers and export to image.

$ lxc stop ubuntu-16-04
$ lxc publish ubuntu-16-04 --alias ubuntu-16-04
Container published with fingerprint:
fdd934c336bbd506c2f4f068a872ccd7504564b50d27d3a168a4835b6cfe4e96

Image can be export to file.

$ lxc image export fdd934c336bbd506c2f4f068a872ccd7504564b50d27d3a168a4835b6cfe4e96

Exported image can be import on other machine.

$ lxc import fdd934c336bbd506c2f4f068a872ccd7504564b50d27d3a168a4835b6cfe4e96.tar.gz

NIC and port for LXD daemon listening is set when sudo lxc init. You can change NIC and port with below command.

$ lxc config set core.https_address 0.0.0.0:8443

You can change password with below command.

$ lxc config set core.trust_password password

Other machine can add this machine as remote server.

$ lxc remote add myimages 192.168.11.77:8443
Certificate fingerprint:
c2e967e5d788db7fbbd19e1f22b789b74313083094bf5585334fe3d15192ab6a
ok (y/n)? y
Admin password for myimages: # type password
Client certificate stored at server:  myimages