LXD is a manager for Linux-based containers (LXC), offering a user experience similar to virtual machines without the same overheads.
Using LXD to install MAAS into containers is a good choice for users who want to test MAAS, or who may want to continue leveraging an existing container architecture or policy.
Quick questions you may have:
- What should I know going into this installation?
- How do I install MAAS with LXD on Ubuntu 16.04/18.04?
- How do i Install MAAS with LXD on Ubuntu 20.04?
Some networking traps
The managed lxdbr0 bridge â recommended below â automatically employs dnsmasq. If you name the LXD container âmaasâ, you can get into a condition where âmaasâ is being resolved by dnsmasq
for the LXD managed bridge rather than maas DNS itself, where the full fqdn is maas.lxd
rather than maas.maas
. Check this post for details.
Also, you may have to broaden the default root user subuid mapping to include the snap_daemon
user. See this post for details and instructions.
Install with LXD (20.04)
Installing LXD for use with MAAS is quite simple:
snap install lxd
lxd init
If you expect to use multiple networks in your MAAS container (for example, libvirt KVMs), youâll want to take the following steps:
lxc profile copy default maas-profile
lxc profile device set maas-profile eth0 network lxdbr0
From here, you can launch your container and install MAAS in the normal way for your chosen version, adding the -p maas-profile
only if you created a special profile for MAAS networking:
lxc launch --profile maas-profile ubuntu:20.04 focal-maas
lxc exec focal-maas bash
Then, proceed with a normal MAAS install in a container.
Install with LXD (16.04/18.04)
MAAS running with LXD has the following requirements:
- a network bridge on the LXD host (e.g. lxdbr0)
- LXD and ZFS
- a container profile
Install LXD and ZFS
Begin by installing LXD and ZFS:
sudo apt install lxd zfsutils-linux
sudo modprobe zfs
sudo lxd init
The sudo lxd init command will trigger a series of configuration questions. Except in the case where the randomly chosen subnet may conflict with an existing one in your local environment, all questions can be answered with their default values.
The bridge network is configured via a second round of questions and is named lxdbr0 by default.
Create a LXC profile for MAAS
First create a container profile by making use of the âdefaultâ profile:
lxc profile copy default maas-profile
Second, bind the network interface inside the container (eth0) to the bridge on the physical host (lxdbr0):
lxc profile device set maas-profile eth0 parent lxdbr0
Thirdly, the maas container profile needs to be edited to include a specific set of privileges. Enter the following to open the profile in your editor of choice:
lxc profile edit maas-profile
And replace the {}
after config with the following (excluding config:
):
config:
raw.lxc: |-
lxc.cgroup.devices.allow = c 10:237 rwm
lxc.apparmor.profile = unconfined
lxc.cgroup.devices.allow = b 7:* rwm
security.privileged: "true"
The final step adds the 8 necessary loop devices to LXC:
for i in `seq 0 7`; do lxc profile device add maas-profile loop$i unix-block path=/dev/loop$i; done
When correctly configured, the above command outputs Device loop0 added to maas-profile
for each loop device.
Launch and access the LXD container
Launch the LXD container:
lxc launch -p maas-profile ubuntu:20.04 focal-maas
Once the container is running, it can be accessed with:
lxc exec focal-maas bash
Then, proceed with a normal MAAS install in a container.