Actually Useful Getting Started Guide to LXD on Ubuntu

OK, this will still be kinda brief, but hopefully helps get you going with LXC containers (via LXD) quickly in a way that’s actually useful.

I have typically used things like Digital Ocean and AWS to quickly launch a testbed, deploy some modified packages and, check the changes and then tear it all down quickly.  This works well for me but I’ve recently been trying to break my dependence on foreign services for this work.  So I’ve been using LXD more and more which is just as fast, and is local so I can do this sort of work without an internet connection if need be.  Below, I’ll outline a few very quick things to make using containers a bit more easy.  Note, all of the info below assumes you are using Ubuntu 16.04 LTS or later, with LXD installed (LXD is installed by default on 16.04 and newer).  Also, you should have at least some familiarity with lxc and lxd.  For more information on those, see https://linuxcontainers.org/lxc/introduction/.

Tip 1:  import images locally with useful aliases.

By default, when you launch a container, the image will be pulled from the internet if it does not already exist.  Also, if you want to use that container base again locally, you sometimes need to find an ugly fingerprint ID to reference it with.  I’ve prefer to locally import the images I want.  Not only does this let me create my own, easily remembered names for this, I can pull a variety of images from various sources and have my own local, off-line catalog of LXD images to create containers from.

First, see what images are available.  Since I do all my work on ubuntu, I only need to check the default ubuntu remote.  This is done with the ‘image’ command for lxc:

 

bladernr@galactica:~$ lxc image list ubuntu:
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| ALIAS | FINGERPRINT | PUBLIC | DESCRIPTION | ARCH | SIZE | UPLOAD DATE |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| p (5 more) | 4c1e4092ead8 | yes | ubuntu 12.04 LTS amd64 (release) (20170417) | x86_64 | 156.78MB | Apr 17, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| p/armhf (2 more) | 68a83fae9fd3 | yes | ubuntu 12.04 LTS armhf (release) (20170417) | armv7l | 135.58MB | Apr 17, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| p/i386 (2 more) | 056784ac045d | yes | ubuntu 12.04 LTS i386 (release) (20170417) | i686 | 141.27MB | Apr 17, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| t (5 more) | 536ea2799fc7 | yes | ubuntu 14.04 LTS amd64 (release) (20170405) | x86_64 | 119.89MB | Apr 5, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| t/arm64 (2 more) | 26b9b1fb1b15 | yes | ubuntu 14.04 LTS arm64 (release) (20170405) | aarch64 | 110.96MB | Apr 5, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| t/armhf (2 more) | 5e367a0ad31c | yes | ubuntu 14.04 LTS armhf (release) (20170405) | armv7l | 111.58MB | Apr 5, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-----------------------------lets--------------------+---------+----------+-------------------------------+
| t/i386 (2 more) | 38df07c91eac | yes | ubuntu 14.04 LTS i386 (release) (20170405) | i686 | 118.24MB | Apr 5, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+

There are a LOT of images available so I’ve trimmed the output significantly.  I’m mostly interested in Trusty for now, which has the alias ‘t’, so let’s import that image locally using the ‘copy’ subcommand of the ‘image’ lxc command:

bladernr@galactica:~$ lxc image copy ubuntu:t local: --alias=ubuntu-trusty
Image copied successfully!
bladernr@galactica:~$ lxc image list
+---------------+--------------+--------+---------------------------------------------+--------+----------+-------------------------------+
| ALIAS | FINGERPRINT | PUBLIC | DESCRIPTION | ARCH | SIZE | UPLOAD DATE |
+---------------+--------------+--------+---------------------------------------------+--------+----------+-------------------------------+
| ubuntu-trusty | 536ea2799fc7 | no | ubuntu 14.04 LTS amd64 (release) (20170405) | x86_64 | 119.89MB | Apr 24, 2017 at 10:58pm (UTC) |
+---------------+--------------+--------+---------------------------------------------+--------+----------+-------------------------------+
| ubuntu-xenial | f452cda3bccb | no | ubuntu 16.04 LTS amd64 (release) (20160627) | x86_64 | 310.30MB | Jul 15, 2016 at 5:55pm (UTC) |
+---------------+--------------+--------+---------------------------------------------+--------+----------+-------------------------------+lets

What this does is download a copy of the arch appropriate trusty container image hosted on the default Ubuntu image store and make it available locally on my desktop.  As you can see, I have both Trusty and Xenial images, with nice aliases that can be easily remembered later on when deploying containers.

I have the release versions of the images, that’s all I need.  Because I’m just prototyping and testing locally, I don’t really worry too much about the latest package updates being installed on my containers.

Ubuntu has two different remotes (streams) to get images from:

bladernr@galactica:~$ lxc image list ubuntu: |head -10
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| ALIAS | FINGERPRINT | PUBLIC | DESCRIPTION | ARCH | SIZE | UPLOAD DATE |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| p (5 more) | 4c1e4092ead8 | yes | ubuntu 12.04 LTS amd64 (release) (20170417) | x86_64 | 156.78MB | Apr 17, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| p/armhf (2 more) | 68a83fae9fd3 | yes | ubuntu 12.04 LTS armhf (release) (20170417) | armv7l | 135.58MB | Apr 17, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| p/i386 (2 more) | 056784ac045d | yes | ubuntu 12.04 LTS i386 (release) (20170417) | i686 | 141.27MB | Apr 17, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-------------------------------------------------+---------+----------+-------------------------------+
| t (5 more) | 9e0493502f9d | yes | ubuntu 14.04 LTS amd64 (release) (20170424) | x86_64 | 120.03MB | Apr 24, 2017 at 12:00am (UTC) |


bladernr@galactica:~$ lxc image list ubuntu-daily: |head -10
+--------------------+--------------+--------+-----------------------------------------------+---------+----------+-------------------------------+
| ALIAS | FINGERPRINT | PUBLIC | DESCRIPTION | ARCH | SIZE | UPLOAD DATE |
+--------------------+--------------+--------+-----------------------------------------------+---------+----------+-------------------------------+
| p (5 more) | 12bb0982a94b | yes | ubuntu 12.04 LTS amd64 (daily) (20170424) | x86_64 | 155.64MB | Apr 24, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-----------------------------------------------+---------+----------+-------------------------------+
| p/armhf (2 more) | d95c2d1be3f8 | yes | ubuntu 12.04 LTS armhf (daily) (20170424) | armv7l | 136.64MB | Apr 24, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-----------------------------------------------+---------+----------+-------------------------------+
| p/i386 (2 more) | 4f516ec69c8f | yes | ubuntu 12.04 LTS i386 (daily) (20170424) | i686 | 139.71MB | Apr 24, 2017 at 12:00am (UTC) |
+--------------------+--------------+--------+-----------------------------------------------+---------+----------+-------------------------------+
| t (5 more) | 9e0493502f9d | yes | ubuntu 14.04 LTS amd64 (daily) (20170424) | x86_64 | 120.03MB | Apr 24, 2017 at 12:00am (UTC) |

The first of those contains only the “release” versions of the Ubuntu images.  That is, the versions that appear on each GA Release Day, or LTS Point Release Day.  The second, ubuntu-daily, provides images from the daily builds of Ubuntu, which are updated far more frequently.  This also gives you access to daily builds of the latest development / interim release such as the soon to be opened Ubuntu 17.10.

Tip 2: Configuring a user for easy login and actually getting work done.

The default Ubuntu images are missing two very important things, ssh keys and a default password for the ‘ubuntu’ user.  There are a few different ways to tackle this.  If a root access is all you need, then this will suffice:

bladernr@galactica:~$ lxc exec subtle-marlin /bin/bash
root@subtle-marlin:~#

This will get you a root login, but I often need to have a non-privileged login.  So the first thing we need to configure the user.  This is accomplished using cloud-init and can be set using the profiles for lxc.  Specifically, I’m setting this in the default profile.  To access/edit this profile, as of lxc version 2.0.7-0ubuntu1~16.04.2, you need to use the lxc profile command to edit the default profile and add a few things.

To edit it use the command lxd profile edit <name> (Note, this command may be different on other versions of lxc, such as lxc edit profile <name>.

bladernr@galactica:~$ lxc profile list
default
docker
juju-controller
juju-default

Note that there are several profiles already created by default.  We’re only interested in the ‘default‘ profile, so let’s edit that:

### This is a yaml representation of the profile.
### Any line starting with a '# will be ignored.
###
### A profile consists of a set of configuration items followed by a set of
### devices.
###
### An example would look like:
### name: onenic
### config:
### raw.lxc: lxc.aa_profile=unconfined
### devices:
### eth0:
### nictype: bridged
### parent: lxdbr0
### type: nic
###
### Note that the name is shown but cannot be changed

config:
 user.vendor-data: |
  #cloud-config
  users:
  - name: ubuntu
    ssh-import-id: bladernr
    lock_passwd: false
    sudo: ALL=(ALL) NOPASSWD:ALL
    shell: /bin/bash
description: ""
devices:
 eth0:
  name: eth0
  nictype: bridged
  parent: lxdbr0
  type: nic
name: default

In that example, I have added modified the user.vendor-data section to set a few items for the “ubuntu” user.  First, I used ssh-import-id to import my own ssh keys.  I believe this pulls from launchpad, but it may pull locally.  I’m honestly not sure which.  Next, I set lock_passwd to ‘false’.  letsIf you leave this unset, it defaults to ‘true’ which will prevent password logins.  Of course, the ssh logins via key are MUCH more secure, but as I mentioned before, these are very short lived development instances, so security is of no concern to me, as proven in the next line.

On this next line, I tell cloud-init to setup sudo privileges for the ‘ubuntu’ user so that no password is required when performing ANY task via sudo.  That is about as close as you can get to using the root user instead.  It is VERY dangerous because anyone who gains access to ‘ubuntu’ now has full, unfettered root access.  So don’t do this at home.  Again, for my use, these are short lived test and dev instances where security is not important.  I would NEVER do this on anthing that is even close to production level.

In fact, on a production system you should probably consider leaving only the ssh-import-id set to only allow logins via ssh and key-based authentication.  You should definitely NOT set sudo as I have done here, also.

Finally, I set the shell to /bin/bash so when I ssh in, I’ll have a nice bash shell.

There are other items you can set in here, such as password, ssh authorized_keys, group membership and so on.  You can find out more about cloud config in the cloudinit documentation.

Conclusion

So there you go.  Those two tips should help setting up LXC/LXD to be much easier and less hassle when launching instances for testing your code, prototyping and other needs.  Please do remember that I do some fairly ugly things (security wise) and you should make better choices there for production.

Once you have those things configured, you should be able to quickly launch instances and connect to them via SSH and be able to perform whatever tasks you need.

 

 bladernr@galactica:~$ lxc list
+---------------+---------+----------------------+------+------------+-----------+
| NAME | STATE | IPV4 | IPV6 | TYPE | SNAPSHOTS |
+---------------+---------+----------------------+------+------------+-----------+
| subtle-marlin | RUNNING | 10.148.80.232 (eth0) | | PERSISTENT | 0 |
+---------------+---------+----------------------+------+------------+-----------+
bladernr@galactica:~$ lxc launch ubuntu-trusty demo
Creating demo
Starting demo
bladernr@galactica:~$ lxc list
+---------------+---------+----------------------+------+------------+-----------+
| NAME | STATE | IPV4 | IPV6 | TYPE | SNAPSHOTS |
+---------------+---------+----------------------+------+------------+-----------+
| demo | RUNNING | 10.148.80.217 (eth0) | | PERSISTENT | 0 |
+---------------+---------+----------------------+------+------------+-----------+
| subtle-marlin | RUNNING | 10.148.80.232 (eth0) | | PERSISTENT | 0 |
+---------------+---------+----------------------+------+------------+-----------+
bladernr@galactica:~$ ssh ubuntu@10.148.80.217
The authenticity of host '10.148.80.217 (10.148.80.217)' can't be established.
ECDSA key fingerprint is SHA256:gyn682YAhs+LyZc7i0s9akfBoZCOnSYErMeds4MbaKI.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '10.148.80.217' (ECDSA) to the list of known hosts.
Welcome to Ubuntu 14.04.5 LTS (GNU/Linux 4.4.0-70-generic x86_64)

* Documentation: https://help.ubuntu.com/

System information as of Tue Apr 25 13:30:23 UTC 2017

System load: 0.77 Memory usage: 0% Processes: 15
 Usage of /home: unknown Swap usage: 47% Users logged in: 0

Graph this data and manage this system at:
 https://landscape.canonical.com/

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.

ubuntu@demo:~$

Getting started with Juju 2.0 on AWS

This is a bit of a first timers guide to setting up Juju 2.0 to work with AWS.  To be honest, it’s been quite a while since I really messed with Juju and AWS (or anything outside of MAAS), and this is the first time I’ve really looked at Juju 2.0 anyway.  So this is me sharing the steps I had to take to get Juju 2 talking to my AWS Virtual Private Cloud (VPC) to spin up instances to prototype things.

First, let’s talk about the parts here.   You should already know what Amazon Web Services is, what a Virtual Private Cloud is, and have an account at Amazon to use them.  You should know a bit about what Juju is as well, but as this is a first timer guide, here’s all you really need to know to get started.  Juju is an amazing tool for modeling complex workload deployments.  It takes all the difficult bits of deploying any workload that has a “Charm” in minutes.  All the brain-share needed to install and configure these workloads is encapsulated in the “Charm”.  To configure, you can pass YAML files with full deployment configuration options, use Juju commands to set individual configuration options, or pass them via the juju gui.  Juju is very extensively documented at https://jujucharms.com, and I highly recommend you RTFM a bit to learn what Juju can do. Continue reading

Setting up Intel AMT to act as a remote KVM in Linux

I’ve been running MAAS for some time now on an Intel NUC, specifically the DC53427HYE model from a few years ago.  There are very few NUC models that offer vPRO support which is why I chose this one to begin with.  It had been running well for quite  a while with Ubuntu 14.04 and MAAS up to version 1.9 from the MAAS stable PPA.  And then tragedy struck…

It all started when I decided I was going to try to upgrade my server to Xenial, the coming Ubuntu 16.04 LTS Alpha.  I realize the perils of running Alpha level stuff, but this box is as much a development box as it is a production server at home, so I chose the risk, and paid the price.  My upgrade, using do-release-upgrade, left me with a half-configured, semi-functional machine and no easy way to recover.  Thus, I decided it was time to just reinstall from scratch.

Truth be told, this was coming anyway.  I’m working on a set of training slides involving my team’s custom MAAS setup for Ubuntu Server Certification so I wanted to get some good screen shots from various stages of building the server and using it.  Thus, I chose to really put AMT to the test on my NUC and see if it could deliver.  Keep in mind, this is a pretty quick run-through, and if it fails, I’ll likely result to something more manual, like the iPhone screen shot method.

First, I needed to reset AMT/MEBx as I had long forgotten the password I originally set.  This is fairly easy on this board (and most NUCs).  You unplug the NUC, crack the case, find the BIOS/MEBx reset pins near the RAM sockets, and jumper pins 1 and 2 for 5 seconds.  Put it all back together, and when the NUC boots, hit CTRL+P to get the MEBx login and you’re back to the original password of “admin”.  You’ll need to change the password on first entry, as before.  You may also need to check the BIOS settings as well to make sure nothing has changed.  Mine did register a CMOS battery failure alert that I cleared from the System Event Log.  Beyond that, at this point AMT is available remotely once you have set the network settings in the MEBx console and enabled Remote Management.

AMT Web Interface

AMT Web Interface

Note, if you have trouble finding the reset pins I mentioned earlier or are not sure which pins are 1 and 2 (there are three pins) refer to the technical manual for your NUC board.  For this particular board, you’re looking for this guide.

Now that MEBx is reconfigured, I wanted to set up remote KVM via the AMT engine.  This proved to be a little more obscure.  There are ways to easily enable this in Windows.  You simply download a Management Console binary, install that along with RealVNC and then do some config and off you go.  Doing this on Linux proved to be a bit more difficult.  To do this, you’ll need to start with wsmancli.  Thankfully, the painful parts (deciphering WSMAN) were already done, and I learned the process by following from this post at serverfault.com.

First, you need to install wsmancli which is available from the Ubuntu repos.

bladernr@sulaco:~$ sudo apt-get install wsmancli

Next, it helps to set up a few shell variables for important things:

bladernr@sulaco:~$ AMT_IP=192.168.0.20
bladernr@sulaco:~$ AMT_PASSWORD=1Nsecure!
bladernr@sulaco:~$ VNC_PASSWORD="1N\$ecure"

Note that for the VNC Password, it must be EXACTLY 8 characters, consisting of at least one of each of these: Lower Case, Upper Case, Number, Special Character. Additionally, I had to escape the ‘$’ since that, itself, is a shell variable.  We’ll see if that way leads to madness.  Remember that you need to escape the ‘$’ here, but when you reference it outside the shell, the exape character ‘\’ shouldn’t be necessary.  Also, it’s probably a better idea to not use ‘$’ as part of the password anyway.  Just sayin’.

Now, we need to configure things using wsmancli:

bladernr@sulaco:~$ # Enable KVM
bladernr@sulaco:~$ wsman put http://intel.com/wbem/wscim/1/ips-schema/1/IPS_KVMRedirectionSettingData -h $AMT_IP -P 16992 -u admin -p ${AMT_PASSWORD} -k RFBPassword=${VNC_PASSWORD}

bladernr@sulaco:~$ # Enable KVM redirection to port 5900
bladernr@sulaco:~$ wsman put http://intel.com/wbem/wscim/1/ips-schema/1/IPS_KVMRedirectionSettingData -h $AMT_IP -P 16992 -u admin -p ${AMT_PASSWORD} -k Is5900PortEnabled=true

bladernr@sulaco:~$ # Disable opt-in policy
bladernr@sulaco:~$ wsman put http://intel.com/wbem/wscim/1/ips-schema/1/IPS_KVMRedirectionSettingData -h $AMT_IP -P 16992 -u admin -p ${AMT_PASSWORD} -k OptInPolicy=false

Now, on that third line, I ran into trouble.  I’m not sure why that one kept failing with this error:

Connection failed. response code = 0
Couldn't resolve host name

When the others worked fine.  So since this is just disabling the default requirement for Opt-In on KVM connections, I went back into MEBx itself.  You can find the setting under User Consent.  Set Opt-In from KVM to None, so that no opt-in is required for remote connections.

bladernr@sulaco:~$ # Disable session timeout
bladernr@sulaco:~$ wsman put http://intel.com/wbem/wscim/1/ips-schema/1/IPS_KVMRedirectionSettingData -h $AMT_IP -P 16992 -u admin -p ${AMT_PASSWORD} -k SessionTimeout=0

bladernr@sulaco:~$ # Enable KVM
bladernr@sulaco:~$ wsman invoke -a RequestStateChange http://schemas.dmtf.org/wbem/wscim/1/cim-schema/2/CIM_KVMRedirectionSAP -h ${AMT_IP} -P 16992 -u admin -p ${AMT_PASSWORD} -k RequestedState=2

These last two first set the session timeout to 0, so that you are never disconnected, and then finally turn KVM on.

I use Remmina for VNC, RDP and similar connections, so I configured a new connection in Remmina and gave it a go.  It failed.  Looking at the debug log, the connection was quickly terminated.  So first I changed the VNC password.

bladernr@sulaco:~$ wsman put http://intel.com/wbem/wscim/1/ips-schema/1/IPS_KVMRedirectionSettingData -h $AMT_IP -P 16992 -u admin -p ${AMT_PASSWORD} -k RFBPassword=Vnc-p@55

The new password was accepted (that was my third attempt at a memorable password that meets all of Intel’s ridiculous requirements.  All things considered, however, I don’t believe the issue was the password.  See the end for the root cause of my issues connecting initially.  Once I had set a new password, I re-configured Remmina and tried again.  And again, failure:

[VNC]VNC server supports protocol version 4.0 (viewer 3.8)
[VNC]We have 2 security types to read
[VNC]0) Received security type 2
[VNC]Selecting security type 2 (0/2 in the list)
[VNC]1) Received security type 128
[VNC]Selected Security Scheme 2
[VNC]VNC authentication succeeded
[VNC]Desktop name "Intel(r) AMT KVM"
[VNC]Connected to VNC server, using protocol version 3.8
[VNC]VNC server default format:
[VNC] 16 bits per pixel.
[VNC] Least significant byte first in each pixel.
[VNC] TRUE colour: max red 31 green 63 blue 31, shift red 11 green 5 blue 0
[VNC]read (104: Connection reset by peer)

But it looks like the password is accepted, so we’re good there.  We’re just missing one piece.

It turns out it was one more bit of annoyance from Intel.  I finally was able to dig up the KVM settings info from Intel after some Googling.  Right there on that page is the following:

If the Intel AMT platform is currently displaying the MEBx, it is not possible to open a KVM session.

I still had MEBx open on the NUC so I could manually change settings if I needed to.  I still don’t know why I was unable to set the Opt-In policy remotely.  That should have worked, but in the end, the result was what I wanted.  I now have KVM control via AMT on my NUC.

Remote KVM via AMT

 

Adventures with Ubuntu Snappy: Prologue

A short while back at IoT World, we introduced a neat little bundle of kit to demonstrate Ubuntu Snappy.  This kit consisted of a Raspberry Pi 2 (the updated Pi that Ubuntu can run on), a PiGlow and really sharp Pibow case, both provided by Pimoroni.  Needless to say, it was a real hit.

An offer came up to get my hands on one of these great, specially made Ubuntu branded versions of the kit and I had to jump on that, because it just looks so darned cool.  Happy coincidence, I was already planning on obtaining a Pi 2 to replace my older RPi that I had toyed with off and on over the last couple years.

Today, my new Ubuntu Snappy Core Raspberry Pi Fun Pack arrived and I had to just stop working and start playing a bit, because, “Hey, new toys!”

So this first post will be an introduction and first steps.Finished. What a sharp looking Raspberry Pi 2. Case and piglow by Pimoroni (http://www.pimoroni.com)OS is Ubuntu Snappy Core (http://developer.ubuntu.com/en/snappy

First, the hardware.  I won’t go into detail on the Raspberry Pi 2 hardware itself.  By now, it’s well known, and it’s well discussed and documented elsewhere to the point where I have nothing Earth shattering to add to that discussion.  You can see some basic information at RaspberryPi.org or search the Goog.

I will point out the two add-on’s though.  First the Pibow case is a plastic case specially made for the Pi 2 and B+ systems.  It consists of two clear panels with several layers of custom designed frames in between.  They sell different configs that range from skeleton cases to full box.  For us, they created one in Ubuntu Orange and laser engraved the Ubuntu logo and Circle of Friends on the top cover.  It looks pretty sharp.

The PiGlow is another neat addition.  It plugs into the pin array on the Pi2 and provides a programmable LED light show.  There are ample instructions for making them flash and I’ll get to a brief demo in another post, perhaps.  The PiGlow is easily programmable with python, and they provide instructions for installing the necessary libraries to interface with the PiGlow via a Python script.  This means it should be quite easy to add a colorful, animated status marker to any python script by adding a few lines of code.  There is video of the PiGlow as well on the Pimoroni site, so enjoy!

Now let’s talk about the OS.  Because of the upgraded ARM Cortex-V7 chip, the Pi 2 can finally run Ubuntu.  Previous incarnations of the RPi used an older ARM v6 chip that Ubuntu was not ported for (though you could get various Debian versions to run on that chip).  In April 2015, we launched Ubuntu 15.04 (Vivid Vervet) and with it came Ubuntu Snappy.  Snappy is a new transactional version of the OS formerly known as Ubuntu Core, thus, Ubuntu Snappy Core.  The key difference is that with Snappy, we no longer use apt to manage package installations.  Instead, packages come in Snaps, which are transactional packages that we first developed for the Ubuntu Phone.  If you’ve never heard of Transactional packages, that’s ok, because you’ve more than likely used them any time you install or update an application on your smartphone.

In a brief nutshell, Transactional Packages are an All-or-Nothing installation that consists of bits of unmodifiable code as well as user-modifiable code.  The unmodifiable parts are the core elements of the application, the UI, the libraries, the binary executables, and so forth.  The user-modifiable parts are things like custom user configurations, downloaded or added data like documents, photos, icons, and other similar things.  When you upgrade an app, you essentially completely replace the unmodifiable bits with the newer version of those bits, unlike traditional package updates that may only update a single library file or binary executable.  One of the two biggest benefits to this are that you never have to worry about update creep, where update after update after update could, possibly, cause things to break as they leave behind old, conflicting or unneeded files.  The other is that if an update breaks, you can very easily roll back to the last working version.  So, for example, if you have Candy Crush version 1.2.3 installed and install 1.2.5 and discover that 1.2.5 is actually broken and you can no longer play Candy Crush, you could simply roll right back to version 1.2.3 and continue on crushing those candies.  And neither the update nor the rollback has touched your user-modifiable data (your records, progress and such in this case).

So the first thing I wanted to do was get this sucker on my network.  My network, however, is very tightly controlled at home.  All IP addresses are handed out by DHCP, on an assigned basis, so if your device’s MAC address isn’t specifically listed in dhcp.conf on my server, you won’t get an address.  And for wireless devices, even connecting to the access point is MAC controlled, so if your phone, tablet or laptop is not on the ACL on the WiFi access point, you can’t even join the network to ask for an IP address.  Sure, it’s not 100% secure, but nothing ever is, and this is “Secure Enough” for my needs and location.

Now, for my first idea, I wanted to replace my home DNS/DHCP server with a small IoT type device like a Raspberry Pi.  I currently use a hacked together Shuttle PC for this purpose, with a giant external 400W power supply that was made necessary because the small Shuttle PSUs are notoriously flaky, and mine didn’t last three months before it started shutting itself off randomly trying to keep up with the power needs of the CPU on the machine.  So that’s a lot of energy being used for a system that essentially does nothing but hand out DHCP requests and answer DNS queries.  Transit also serves as a bastion point so I can access my LAN remotely so I will try to set this up to do likewise.

First, however, I need the Snappy Pi to have a static IP address.  By default, it comes configured for dynamic addressing for it’s onboard ethernet device.  So I needed to modify /etc/network/interfaces.d/eth0eth0-orig

 

To change the file, a couple things had to happen.  First, I needed to be the root user.  Sudo may have worked, but it’s just as easy to become root to do a lot of things.  So sudo -i to become root.

Now, we just need to edit the file.  There is a problem though.  The root filesystem is mounted read-only by default.  This is great for security, but when you need to edit core files, it makes things a bit difficult.  So, you need to remount the root filesystem read-write so you can edit the core files that are not already designed to be user-writable (learn about the Snappy Core filesystem).  This is simply accomplished like so:

root@localhost:/etc/network/interfaces.d# mount -o remount,rw /

after this, you should be able to edit the eth0 file to use a static addresseth0-fixedI edited the file to add the address, netmask, broadcast and gateway lines and saved the eth0 file.  Then, I shut the interface down and brought it back up and I was in business.  I also took a moment to verify that it all worked by rebooting the RPi.  This highlights a couple things:

  1. On reboot, the root filesystem is again mounted read-only, so if you need to modify more core files, you will need to remount the filesystem once more.
  2. allow-hotplug is an interesting thing.  It’s intention is to only bring the device up on hotplug events.  However, because the ethernet device is always plugged in, on reboot, the kernel detects a hotplug event and brings the device up at boot time, regardless.  That means, if you don’t have it plugged in to a switch and turn it on, you could wait a bit while it tries to obtain a dhcp address.  I noted that after rebooting the RPi with the ethernet cable removed, the eth0 device was still shown as up with the prescribed IP address.

One thing I forgot to mention was that because I’m not using DHCP, I also need to list some nameservers.  Eventually, this file will list itself as it will be running Bind9, but for now, I’m going to give it Google’s public DNS addresses by creating a file called “tail” in /etc/resolvconf/resolv.conf.d that looks simply like this:

ubuntu@localhost:~$ cat /etc/resolvconf/resolv.conf.d/tail 
nameserver 8.8.8.8
nameserver 8.8.4.4

Now that I’m rebooted and have an IP address, lets take a brief whirlwind tour of Snappy before I end this prologue to my Snappy Adventure.

As I mentioned before, Snappy doesn’t use apt to manage packages, it uses a new tool called, not surprisingly, “snappy”.  So first, lets get just a bit of information about my system

ubuntu@localhost:~$ snappy info
release: ubuntu-core/devel
frameworks: webdm
apps:

 

 

So there you have it… there is much more available at https://developer.ubuntu.com/en/snappy/tutorials/ about snappy and its use.

I can deploy a full Openstack cloud in under 75 minutes… We’re that f#@$ing cool.

openstackI’ve been in Taiwan for the last week and a half working with a customer on a proof of concept solution. All that time was spent setting up and tearing down and rebuilding a fully HA OpenStack Icehouse deployment using Juju and MAAS and Ubuntu 14.04. But the highlight of the week is one of the coolest things we have done in a while.

So you have the background, what I’m about to describe uses the three biggest tools that Canonical produces for the server space. MAAS, Metal-As-A-Service is a bare metal management system that handles provisioning of Ubuntu (and other OSes) in a quick and repeatable way on bare metal, maasbe that on traditional servers or the newer scale-out density server systems like the SeaMicro SM15000, HP Moonshot, and similar.

The next piece is Juju. Juju does for software what MAAS does for hardware. It’s a service orchestration tool that allows you to rapidly deploy services like Hadoop, LAMP stacks, OpenStack, Nagios, OpenVSwitch and pretty much anything you can imagine. And even better, with Juju you can deploy these services just about anywhere you’d want to, from AWS to Azure to Digital Ocean, on Virtual Machines, on a single machine, anywhere in LXC or in this case, to bare metal using MAAS as the provisioning system.

The final piece of puzzle is Canonical’s datacenter management tool called Landscape. Landscape provides a means to manage all your hardware in one location, handling system updates, security alerts, users and so forth. And now, it provides a means to very, VERY easily deploy OpenStack, a task that is not at all trivial.

Recently, Canonical announced The Canonical Distribution of Openstack. This is our way of giving you a cloud, on your hardware, in the easiest way you can imagine. The first time I saw this work, sitting at UTSA to set up a demo for the OpenCompute Summit in Paris, I felt giddy and thought, “This is fucking cool.” And it is.

landscapeUsing Landscape, MAAS and Juju, we have reduced an OpenStack deployment to a few mouse clicks. Once you have MAAS configured and hardware commissioned and ready to roll, you install Landscape using our openstack-installer tool. After that, getting OpenStack running is simply a matter of registering the MAAS server so Landscape knows about the hardware, choosing a few options and away you go.

For now, it’s in Public Beta and the options are limited but more are scheduled and coming in the near future. In essence, if you can plug it into an OpenStack deployment, we want you to be able to do so as easily and smoothly as possible.  Currently, the only hypervisor is KVM though support for other hypervisors is planned. For networking, OpenVSwitch is the way we roll. Object storage is provided by one of either Ceph or Swift and Block Storage is provided by either Ceph or Cinder (via iSCSI). Once you’ve selected your components, you simply need to select the hardware you want to deploy.

For Hardware, you need a minimum of 5 registered systems in MAAS, which need 2 hard drives each and one of which needs to have two NICs on valid networks. The 2-NIC system is used for Quantum Gateway. The second hard disk in each node is used for the Ceph or Swift storage clusters. Once you’ve selected your hardware, you simply click “Install” and wait.

Landscape will give you a status/progress report and when it’s done it will show you your new Cloud, give you the URL and access credentials for the OpenStack Dashboard (Horizon) as well as the openstack credentials (private key). From there you can log into the dashboard, create an instance (it downloads Ubuntu 14.04 and 12.04 by default, but you can add any cloud image you want via Glance) and you’re in business.

And all that, from the time you click Install to the time you log into the Dashboard, takes less than 75 minutes. And that time was on a system with small 2.5″ hard drives spinning at 5400 RPM. On a system with pure SSD storage, it would be a whole lot faster.  Use a local mirror of the Ubuntu archives rather than the internet and the speed increases even more.

So there we sat, walking a Vice President through 6 or 7 mouse clicks to a full OpenStack Juno deployment and yeah, it was that fucking cool.

Horizon