Unexpected errors from LXC

shell session

adams ~$ sudo lxc-create -t download -n test-ubuntu -- -d ubuntu -r trusty -a amd64 ; sudo lxc-start -n test-ubuntu -d ; sudo lxc-ls -f test-ubuntu ; sudo lxc-stop -n test-ubuntu -k ; sudo lxc-destroy -n test-ubuntu
Setting up the GPG keyring
Downloading the image index
Downloading the rootfs
Downloading the metadata
The image cache is now ready
Unpacking the rootfs

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You just created an Ubuntu container (release=trusty, arch=amd64, variant=default)
The default username/password is: ubuntu / ubuntu
To gain root privileges, please use sudo.

lxc_container: Invalid argument - failed to setns for CLONE_NEWNET
lxc_container: Invalid argument - failed to enter namespace
lxc_container: Invalid argument - failed to setns for CLONE_NEWNET
lxc_container: Invalid argument - failed to enter namespace
NAME         STATE    IPV4  IPV6  AUTOSTART  
-------------------------------------------
test-ubuntu  RUNNING  -     -     NO         
adams ~$