One to read: A Beginner’s Guide to IPFS

One to read: “A Beginner’s Guide to IPFS”

Ever wondered about IPFS (the “Inter Planetary File System”) – a new way to share and store content. This doesn’t rely on a central server (e.g. Facebook, Google, Digital Ocean, or your home NAS) but instead uses a system like bittorrent combined with published records to keep the content in the system.

If your host goes down (where the original content is stored) it’s also cached on other nodes who have visited your site.

These caches are cleared over time, so are suitable for short outages, or you can have other nodes who “pin” your content (and this can be seen as a paid solution that can fund hosts).

IPFS is great at hosting static content, but how to deal with dynamic content? That’s where PubSub comes into play (which isn’t in this article). There’s a database service which sits on IPFS and uses PubSub to sync data content across the network, called Orbit-DB.

It’s looking interesting, especially in light of the announcement from CloudFlare about their introduction of an available IPFS gateway.

It’s looking good for IPFS!

This was automatically posted from my RSS Reader, and may be edited later to add commentary.

One to read/watch: IPsec and IKE Tutorial

Ever been told that IPsec is hard? Maybe you’ve seen it yourself? Well, Paul Wouters and Sowmini Varadhan recently co-delivered a talk at the NetDev conference, and it’s really good.

Sowmini’s and Paul’s slides are available here: https://www.files.netdevconf.org/d/a18e61e734714da59571/

A complete recording of the tutorial is here. Sowmini’s part of the tutorial (which starts first in the video) is quite technically complex, looking at specifically the way that Linux handles the packets through the kernel. I’ve focused more on Paul’s part of the tutorial (starting at 26m23s)… but my interest was piqued from 40m40s when he starts to actually show how “easy” configuration is. There are two quick run throughs of typical host-to-host IPsec and subnet-to-subnet IPsec tunnels.

A key message for me, which previously hadn’t been at all clear in IPsec using {free,libre,open}swan is that they refer to Left and Right as being one party and the other… but the node itself works out if it’s “left” or “right” so the *SAME CONFIG* can be used on both machines. GENIUS.

Also, when you’re looking at the config files, anything prefixed with an @ symbol is something that doesn’t need resolving to something else.

It’s well worth a check-out, and it’s inspired me to take another look at IPsec for my personal VPNs :)

I should note that towards the end, Paul tried to run a selection of demonstrations in Opportunistic Encryption (which basically is a way to enable encryption between two nodes, even if you don’t have a pre-established VPN with them). Because of issues with the conference wifi, plus the fact that what he’s demoing isn’t exactly production-grade yet, it doesn’t really work right, and much of the rest of the video (from around 1h10m) is him trying to show that working while attendees are running through the lab, and having conversations about those labs with the attendees.

Podcast/Talk Summary – OggCamp “Main stage ‘Extravaganza'”

Format: Five podcasting guys standing in front of an audience. No slides. Discussion. 200ish attendees

Audio: https://latenightlinux.com/late-night-linux-extra-episode-05/

Slot: Slot 9 Saturday (Closing Session) 16:00-17:00

Notes: My first main stage show. Two questions proposed by the podcasters and a discussion with the audience. Slightly waffly on my part, mostly because I was tired. I also was taking the “mic around to the audience”. Skilfully mastered by Joe Ressington.

Well worth a listen – I’d like to know your views on anything raised in the podcast in the comments!

Oh, and at the end, I tried to make a point, but couldn’t remember the exact quote – here it is: “Be who you needed when you were younger” – Brad Montague

Enjoy :)

Experiments with USBIP on Raspberry Pi

At home, I have a server on which I run my VMs and store my content (MP3/OGG/FLAC files I have ripped from my CDs, Photos I’ve taken, etc.) and I want to record material from FreeSat to play back at home, except the server lives in my garage, and the satellite dish feeds into my Living Room. I bought a TeVii S660 USB FreeSat decoder, and tried to figure out what to do with it.

I previously stored the server near where the feed comes in, but the running fan was a bit annoying, so it got moved… but then I started thinking – what if I ran a Raspberry Pi to consume the media there.

I tried running OpenElec, and then LibreElec, and while both would see the device, and I could even occasionally get *content* out of it, I couldn’t write quick enough to the media devices attached to the RPi to actually record what I wanted to get from it. So, I resigned myself to the fact I wouldn’t be recording any of the Christmas Films… until I stumbled over usbip.

USBIP is a service which binds USB ports to a TCP port, and then lets you consume that USB port on another machine. I’ll discuss consuming the S660’s streams in another post, but the below DOES work :)

There are some caveats here. Because I’m using a Raspberry Pi, I can’t just bung on any old distribution, so I’m a bit limited here. I prefer Debian based images, so I’m going to artificially limit myself to these for now, but if I have any significant issues with these images, then I’ll have to bail on Debian based, and use something else.

  1. If I put on stock Raspbian Jessie, I can’t use usbip, because while ships its own kernel that has the right tools built-in (the usbip_host, usbip_core etc.), it doesn’t ship the right userland tools to manipulate it.
  2. If I’m using a Raspberry Pi 3, there’s no supported version of Ubuntu Server which ships for it. I can use a flavour (e.g. Ubuntu Mate), but that uses the Raspbian kernel, which, as I mentioned before, is not shipping the right userland tools.
  3. If I use a Raspberry Pi 2, then I can use Stock Ubuntu, which ships the right tooling. Now all I need to do is find a CAT5 cable, and some way to patch it through to my network…

Getting the Host stood up

I found most of my notes on this via a wiki entry at Github but essentially, it boils down to this:

On your host machine, (where the USB port is present), run

sudo apt-get install linux-tools-generic
sudo modprobe usbip_host
sudo usbipd -D

This confirms that your host can present the USB ports over the USBIP interface (there are caveats! I’ll cover them later!!).

You now need to find which ports you want to serve. Run this command to list the ports on your system:

lsusb

You’ll get something like this back:

Bus 001 Device 004: ID 9022:d662 TeVii Technology Ltd.
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. SMC9514 Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

And then you need to find which port the device thinks it’s attached to. Run this to see how usbip sees the world:

usbip list -l

This will return:

- busid 1-1.1 (0424:ec00)
unknown vendor : unknown product (0424:ec00)
- busid 1-1.3 (9022:d662)
unknown vendor : unknown product (9022:d662)

We want to share the TeVii device, which has the ID 9022:d662, and we can see that this is present as busid 1-1.3, so we now we need to bind it to the usbip system, with this command:

usbip bind -b 1-1.3

OK, so now we’re presenting this to the system. Perhaps you might want to make it available on a reboot?

echo "usbip_host" >> /etc/modules

I also added @reboot /usr/bin/usbipd -D ; sleep 5 ; /usr/bin/usbip bind -b 1-1.3 to root’s crontab, but it should probably go into a systemd unit.

Getting the Guest stood up

All these actions are being performed as root. As before, let’s get the modules loaded in the kernel:

apt-get install linux-tools-generic
modprobe vhci-hcd

Now, we can try to attach the module over the wire. Let’s check what’s offered to us (this code example uses 192.0.2.1 but this would be the static IP of your host):

usbip list -r 192.0.2.1

This hands up back the list of offered appliances:

Exportable USB devices
======================
- 192.0.2.1
1-1.3: TeVii Technology Ltd. : unknown product (9022:d662)
: /sys/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.3
: (Defined at Interface level) (00/00/00)
: 0 - Vendor Specific Class / unknown subclass / unknown protocol (ff/01/01)

So, now all we need to do is attach it:

usbip attach -r 192.0.2.1 -b 1-1.3

Now I can consume the service from that device in tvheadend on my server. However, again, I need to make this persistent. So, let’s make sure the module is loaded on boot.

echo 'vhci-hcd' >> /etc/modules

And, finally, we need to attach the port on boot. Again, I’m using crontab, but should probably wrap this into a systemd service.

@reboot /usr/bin/usbip attach -r 192.0.2.1 -b 1-1.3

And then I had an attached USB device across my network!

Unfortuately, the throughput was a bit too low (due to silly ethernet-over-power adaptors) to make it work the way I wanted… but theoretically, if I had proper patching done in this house, it’d be perfect! :)

Interestingly, the day I finished this post off (after it’d sat in drafts since December), I spotted that one of the articles in Linux Magazine is “USB over the network with USB/IP”. Just typical! :D

Using Python-OpenstackClient and Ansible with K5

Recently, I have used K5, which is an instance of OpenStack, run by Fujitsu (my employer). To do some of the automation tasks I have played with both python-openstackclient and Ansible. This post is going to cover how to get those tools to work with K5.

I have access to a Linux virtual machine (Ubuntu 16.04) and the Windows Subsystem for Linux in Windows 10 to run “Bash on Ubuntu on Windows”, and both accept the same set of commands.

In order to run these commands, you need a couple of dependencies. Your mileage might vary with other Linux distributions, but, for Ubuntu based distributions, run this command:

sudo apt install python-pip build-essential libssl-dev libffi-dev python-dev

Next, use pip to install the python modules you need:

sudo -H pip install shade==1.11.1 ansible cryptography python-openstackclient

If you’re only ever going to be working with a single project, you can define a handful of environment variables prefixed OS_, like this:

export OS_USERNAME=BloggsF
export OS_PASSWORD=MySuperSecretPasswordIsHere
export OS_REGION_NAME=uk-1
export OS_USER_DOMAIN_NAME=YourProjectName
export OS_PROJECT_NAME=YourProjectName-prj
export OS_PROJECT_ID=baddecafbaddecafbaddecafbaddecaf
export OS_AUTH_URL=https://identity.uk-1.cloud.global.fujitsu.com/v3
export OS_VOLUME_API_VERSION=2
export OS_IDENTITY_API_VERSION=3

But, if you’re working with a few projects, it’s probably worth separating these out into clouds.yml files. This would be stored in ~/.config/openstack/clouds.yml with the credentials for the environment you’re using:

---
clouds:
  root:
    identity_api_version: 3
    regions:
    - uk-1
    auth:
      auth_url: https://identity.uk-1.cloud.global.fujitsu.com/v3
      password: MySuperSecretPasswordIsHere
      project_id: baddecafbaddecafbaddecafbaddecaf
      project_name: YourProjectName-prj
      username: BloggsF
      user_domain_name: YourProjectName

Optionally, you can separate out the password, username or any other “sensitive” information into a secure.yml file stored in the same location (removing those lines from the clouds.yml file), like this:

---
clouds:
  root:
    auth:
      password: MySuperSecretPasswordIsHere

Now, you can use the Python based Openstack Client, using this invocation:

openstack --os-cloud root server list

Alternatively you can use the Ansible Openstack (and K5) modules, like this:

---
tasks:
- name: "Authenticate to K5"
  k5_auth:
    cloud: root
  register: k5_auth_reg
- name: "Create Network"
  k5_create_network:
    name: "Public"
    availability_zone: "uk-1a"
    state: present
    k5_auth: "{{ k5_auth_reg.k5_auth_facts }}"
- name: "Create Subnet"
  k5_create_subnet:
    name: "Public"
    network_name: "Public"
    cidr: "192.0.2.0/24"
    gateway_ip: "192.0.2.1"
    availability_zone: "uk-1a"
    state: present
    k5_auth: "{{ k5_auth_reg.k5_auth_facts }}"
- name: "Create Router"
  k5_create_router:
    name: "Public"
    availability_zone: "uk-1a"
    state: present
    k5_auth: "{{ k5_auth_reg.k5_auth_facts }}"
- name: "Attach private network to router"
  os_router:
    name: "Public"
    state: present
    network: "inf_az1_ext-net02"
    interfaces: "Public"
    cloud: root
- name: "Create Servers"
  os_server:
    name: "Server"
    availability_zone: "uk-1a"
    flavor: "P-1"
    state: present
    key_name: "MyFirstKey"
    network: "Public-Network"
    image: "Ubuntu Server 14.04 LTS (English) 02"
    boot_from_volume: yes
    terminate_volume: yes
    security_groups: "Default"
    auto_ip: no
    timeout: 7200
    cloud: root

Using riot.im as a bridge to Freenode

Over the last few months, I’ve been using Riot.im (the client for Matrix.org) as my primary IRC client, and access to other end-to-end-encrypted chats.

A few weeks ago I decided I wanted to use my “normal” IRC nickname on Freenode, so looked into how to do it. It’s surprisingly easy, but there are a few gotchas.

Making Matrix know your password

First of all you need to message the IRC bridge bot and tell it your nickserv password: !storepass chat.freenode.net MyComplexPassword

Next, you need to chat with NickServ directly and authenticate with it: identify MyNormalNick MyComplexPassword

Lastly, you go back to your chat with the bridge bot, and tell it your nickname: !nick chat.freenode.net MyNormalNick

If, in the process of doing this, you find you can’t log in as yourself, message NickServ and tell it to release your account from being protected: release MyNormalNick MyComplexPassword

Setting topics

While the bridge bot will let you set a topic (!cmd TOPIC #channel Something) this didn’t really work for me, so instead, I use ChanServ to do it for me: topic #channel My New Topic

Just remember that you must have ops granted to you for that channel through ChanServ to be able to make such changes.

You can also set modes for people, or the channel, ban people, voice or op them through ChanServ, just send the command help in the chat to ChanServ for more guidance!

And, if you’re stuck, feel free to come ask for help! I’m (predictably) JonTheNiceGuy!