Category: General

Using cloud-init with SmartOS

SmartOS provides the ability to inject cloud-init data into a zone/VM. This is extremely useful for automating some of the menial tasks one would normally have to perform manually like setting up users, installing packages, or pulling down a git repo. Basically, anything you can stuff into cloud-init user-data is at your disposal.

However, since SmartOS zone definitions are in JSON and cloud-init data is in yaml, it’s not immediately obvious how to supply this information. What it boils down to is, escape all double-quotes (“) and line-feeds.

Here’s our cloud-init config which creates a new user and import their ssh key from launchpad.net.

#cloud-config

users:
  - default
  - name: shaner
    ssh_import_id: shaner
    lock_passwd: false
    sudo: "ALL=(ALL) NOPASSWD:ALL"
    shell: /bin/bash

So following the above escape rules above, here’s our full SmartOS zone spec, including the cloud-init data. Note the cloud-init:user-data key.

{
  "brand": "kvm",
  "alias": "ubuntu-xenial",
  "ram": "2048",
  "vcpus": "2",
  "resolvers": [
    "192.168.1.1",
    "1.1.1.1"
  ],
  "nics": [
    {
      "nic_tag": "admin",
      "ip": "192.168.1.50",
      "netmask": "255.255.255.0",
      "gateway": "192.168.1.1",
      "model": "virtio",
      "primary": true
    }
  ],
  "disks": [
    {
      "image_uuid": "429bf9f2-bb55-4c6f-97eb-046fa905dd03",
      "boot": true,
      "model": "virtio"
    }
  ],
  "customer_metadata": {
    "cloud-init:user-data": "#cloud-config\n\nusers:\n  - default\n  - name: shaner\n    ssh_import_id: shaner\n    lock_passwd: false\n    sudo: \"ALL=(ALL) NOPASSWD:ALL\"\n    shell: /bin/bash"
  }
}

Let’s go ahead and create the zone on our SmartOS box.

[root@vmm01 /opt/templates]# vmadm create < ubuntu-xenial.json
Successfully created VM 0e908925-600a-4365-f161-b3a51467dc08
[root@vmm01 /opt/templates]# vmadm list 
UUID                                  TYPE  RAM      STATE             ALIAS
0e908925-600a-4365-f161-b3a51467dc08  KVM   2048     running           ubuntu-xenial

After a bit of time, we can try logging in as our new user we requested. Recall, we asked cloud-init to pull in our public ssh key from launchpad so, if you get prompted for a password, something is wrong.

shaner@tp25:~$ ssh 192.168.1.50
The authenticity of host '192.168.1.50 (192.168.1.50)' can't be established.
ECDSA key fingerprint is SHA256:hFPjwUJjd7N/Gb9EE37fTVt2Lk6NVzoLKvhFN7wYw2M.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.1.50' (ECDSA) to the list of known hosts.
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.4.0-116-generic x86_64)
Certified Ubuntu Cloud Image

   __        .                   .
 _|  |_      | .-. .  . .-. :--. |-
|_    _|     ;|   ||  |(.-' |  | |
  |__|   `--'  `-' `;-| `-' '  ' `-'
                   /  ;  Instance (Ubuntu 16.04.3 LTS 20180222)
                   `-'   https://docs.joyent.com/images/linux/ubuntu-certified
                         http://www.ubuntu.com/cloud#joyent

 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/advantage

  Get cloud support with Ubuntu Advantage Cloud Guest:
    http://www.ubuntu.com/business/services/cloud

0 packages can be updated.
0 updates are security updates.



The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

shaner@0b8d7a26-ffe4-e859-eb56-d96d02bf213e:~$ sudo ls
shaner@0b8d7a26-ffe4-e859-eb56-d96d02bf213e:~$ sudo apt-update && sudo apt-upgrade -y

There’s a LOT you can do with cloud-init data. See the below links for more info.

Cloud-init examples: https://cloudinit.readthedocs.io/en/latest/topics/examples.html
Joyent Datasource: https://github.com/number5/cloud-init/blob/master/cloudinit/sources/DataSourceSmartOS.py
Joyent Ubuntu Image documentation: https://docs.joyent.com/public-cloud/instances/virtual-machines/images/linux/ubuntu-certified