Manually provision an existing LXC container in Juju-local

Question

Is it possible to manually provision an existing LXC controller in juju (1.24)?

I have tried following (ubuntu-trusty):

1. Setup juju local
2. Create an lxc container, install systemd-services and dbus-x11 packages in the contrainer
3. Manually provision the container through Ssh (juju add-machine ssh:user@container-ip)
4. Remove following line from agent.conf in the container ("- localhost:17070") and restart jujud in container. This was required, or juju-agent in the container will remain in pending state.
5. Deploy mysql to the continer using --to juju switch

MysqL charm deployment starts, takes a long itme, and then "install hook" fails.

Doing manual provision using a KVM machine works (though I have to do step 4 anyway, or agent state will remain pending).

I am doing a clustered installation of MySQL, and want to use LXC (instead of KVM) on multiple physical machines, due to LXC being comparitively light weight.

Thanks for any hints.

Answer 1

I figured-out a solution myself:

After bootstrapping a fresh juju local environment, add a machine to the environment:

juju add-machine

This shall create machine-1. After the machine-1 is ready (check through juju status), a juju template would have been created named similar to juju-trusty-lxc-template.

Now you can create clones of this template to create as many lxc-containers you want, and add them to juju environment manually (this can be created on a remote machine as well) through ssh.

sudo lxc-clone juju-trusty-lxc-template -n lxc-001
sudo lxc-clone juju-trusty-lxc-template -n lxc-002

Start the containers

sudo lxc-start -d -n lxc-001
sudo lxc-start -d -n lxc-002

and then add the the containers to juju through ssh

juju add-machine ssh:lxc-001 #this shall create machine-2
juju add-machine ssh:lxc-002 #this shall create machine-3

After juju finishes installing agents on the machine, you have to remove reference to localhost:170702 in agent.conf file inside containers and restart jujud inside continers. You can quickly do this through:

juju run --machine 2 'sudo sed -i "s/\- localhost:17070//" /var/lib/juju/agents/machine-*/agent.conf && sudo pkill jujud -hup'
juju run --machine 3 'sudo sed -i "s/\- localhost:17070//" /var/lib/juju/agents/machine-*/agent.conf && sudo pkill jujud -hup'

Check through juju status if agents are in started state, and you are done, ready to deploy a service to these machines.

Hope this helps.

Note: In default juju configuration, lxc containers will get DHCP address from bridge created from juju. These addresses are not accessable on LAN. You may want to create a custom bridge and let juju use that (change network-bridge: your-lan-br0 in ~/.juju/environments.yaml before bootstrapping). This is also necessary if you add a container from another physical machine. You may also want to configure static addresses for lxc-containers (dnsmasq).