Besides the default base os image, you may download additional images with different OS's. Look at the GitHub listing for list of supported templates. (what are the rules on this? ie I would guess only can run containers that are older than the base?).
Where is the website? Where does it download to and how long is it kept. When container created where is it located and what are the key config files?
# create container and downloaded in one step,
sudo lxc-create --template download --name my-container
# will download a list to show
# pick version,
# will receive prompts about downloading which may take a while
Downloading the image index
Downloading the rootfs
Downloading the metadata
The image cache is now ready
Unpacking the rootfs
You just created an Ubuntu container (release=trusty, arch=amd64, variant=default)
To enable sshd, run: apt-get install openssh-server
For security reason, container images ship without user accounts
and without a root password.
Use lxc-attach or chroot directly into the rootfs to set a root password
or create user accounts.
If you already know the exact distribution, release and architecture you may run as one command,
sudo lxc-create --template download --name my-container -- --dist ubuntu --release trusty --arch amd64