HOWTO: Automatically import your public SSH keys into LXD Instances

Just another reason why LXD is so awesome…

You can easily configure your own cloud-init configuration into your LXD instance profile.

In my case, I want cloud-init to automatically ssh-import-id kirkland, to fetch my keys from Launchpad.  Alternatively, I could use gh:dustinkirkland to fetch my keys from Github.

Here’s how!

First, edit your default LXD profile (or any other, for that matter):

$ lxc profile edit default

Then, add the config snippet, like this:

config:
user.vendor-data: |
#cloud-config
users:
- name: root
ssh-import-id: gh:dustinkirkland
shell: /bin/bash
description: Default LXD profile
devices:
eth0:
name: eth0
nictype: bridged
parent: lxdbr0
type: nic
name: default

Save and quit in your interactive editor, and then launch a new instance:

$ lxc launch ubuntu:x
Creating amazed-manatee
Starting amazed-manatee

Find your instance’s IP address:

$ lxc list
+----------------+---------+----------------------+----------------------------------------------+------------+-----------+
| NAME | STATE | IPV4 | IPV6 | TYPE | SNAPSHOTS |
+----------------+---------+----------------------+----------------------------------------------+------------+-----------+
| amazed-manatee | RUNNING | 10.163.22.135 (eth0) | fdce:be5e:b787:f7d2:216:3eff:fe1c:773 (eth0) | PERSISTENT | 0 |
+----------------+---------+----------------------+----------------------------------------------+------------+-----------+

And now SSH in!

$ ssh ubuntu@10.163.22.135
$ ssh -6 ubuntu@fdce:be5e:b787:f7d2:216:3eff:fe1c:773

Enjoy!

:-Dustin

About the author

Dustin's photo

Dustin Kirkland is part of Canonical's Ubuntu Product and Strategy team, working for Mark Shuttleworth, and leading the technical strategy, road map, and life cycle of the Ubuntu Cloud and IoT commercial offerings. Formerly the CTO of Gazzang, a venture funded start-up acquired by Cloudera, Dustin designed and implemented an innovative key management system for the cloud, called zTrustee, and delivered comprehensive security for cloud and big data platforms with eCryptfs and other encryption technologies. Dustin is an active Core Developer of the Ubuntu Linux distribution, maintainer of 20+ open source projects, and the creator of Byobu, DivItUp.com, and LinuxSearch.org. A Fightin' Texas Aggie Class of 2001 graduate, Dustin lives in Austin, Texas, with his wife Kim, daughters, and his Australian Shepherds, Aggie and Tiger. Dustin is also an avid home brewer.

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