Category Archives: Ubuntu

Ubuntu cloud images and how to find the most recent cloud image


sstream-query --json --max=1 --keyring=/usr/share/keyrings/ubuntu-cloudimage-keyring.gpg arch=amd64 release_codename='Xenial Xerus' ftype='disk1.img' | jq -r '.[].item_url'

This will show you the URL for the most recent Ubuntu 16.04 Xenial cloud image in QCOW format.

There are a few ways to find the most recent Ubuntu cloud image an the simplest method is to view the release page which lists the most recent release.

Another method is to use the cloud image simple streams data which we also update every time we (I work on the Certified Public Cloud team @ Canonical) publish an image.

We publish simple streams data for major public clouds too but this post deals with the base Ubuntu cloud image. I will follow up this post with details on how to use the cloud specific streams data.

Simple streams

Simple streams is a structured format describing the Ubuntu cloud image releases.

You can parse the Ubuntu’s release cloud image stream json yourself or you can use a combination of sstream-query and jq (install packages “ubuntu-cloudimage-keyring“, “simplestreams” and “jq“) to get all or specific data about the most recent release.

Query all data from most recent release

sstream-query --json --max=1 --keyring=/usr/share/keyrings/ubuntu-cloudimage-keyring.gpg arch=amd64 release='xenial' ftype='disk1.img'

This will return all data on the release including date released and also the checksums of the file.

 "aliases": "16.04,default,lts,x,xenial",
 "arch": "amd64",
 "content_id": "",
 "datatype": "image-downloads",
 "format": "products:1.0",
 "ftype": "disk1.img",
 "item_name": "disk1.img",
 "item_url": "",
 "label": "release",
 "license": "",
 "md5": "9cb8ed487ad8fbc8b7d082968915c4fd",
 "os": "ubuntu",
 "path": "server/releases/xenial/release-20180126/ubuntu-16.04-server-cloudimg-amd64-disk1.img",
 "product_name": "",
 "pubname": "ubuntu-xenial-16.04-amd64-server-20180126",
 "release": "xenial",
 "release_codename": "Xenial Xerus",
 "release_title": "16.04 LTS",
 "sha256": "da7a59cbaf43eaaa83ded0b0588bdcee4e722d9355bd6b9bfddd01b2e7e372e2",
 "size": "289603584",
 "support_eol": "2021-04-21",
 "supported": "True",
 "updated": "Wed, 07 Feb 2018 03:58:59 +0000",
 "version": "16.04",
 "version_name": "20180126"

Query only the url to the most recent release

sstream-query --json --max=1 --keyring=/usr/share/keyrings/ubuntu-cloudimage-keyring.gpg arch=amd64 release_codename='Xenial Xerus' ftype='disk1.img' | jq -r '.[].item_url'

This will show you the URL for the most recent Ubuntu 16.04 Xenial cloud image in QCOW format.


Query only the serial of the most recent release

sstream-query --json --max=1 --keyring=/usr/share/keyrings/ubuntu-cloudimage-keyring.gpg arch=amd64 release_codename='Xenial Xerus' ftype='disk1.img' | jq ".[].version_name"

This will show you the serial of the most recent Ubuntu 16.04 Xenial cloud image.


The above streams are signed using keys in the ubuntu-cloudimage-keyring keyring but you can replace the –keyring option with –no-verify to bypass any signing checks. Another way to bypass the checks is to to use the unsigned streams.

It is also worth noting that OpenStack can be configured to use streams too.

I hope the above is helpful with your automation.

Xerox DocuMate 3220 scanner on Ubuntu

TLDR; This blog post is confirming that the Xerox DocuMate 3220 does work on Ubuntu and shows how to add permissions for non root users to use it.


I was using my wife’s old printer/scanner all in one for scanning documents and it worked well but it was a pain to scan multiple documents so I decided to get a business scanner with auto feed and duplex scanning.

I went for the Xerox DocuMate 3220 as it stated it was SANE compatible so would work on Linux.


With an RRP of ~€310 I managed to get a refurbished model for €98 delivered from ebay but sadly I didn’t do enough research as the scanner is not SANE supported.

In my research in trying to add the scanner to the xerox_mfp SANE backend config (which didn’t work) I discovered that VueScan was available for Linux and it’s supported scanners did list some of the Xerox DocuMate series. I had used VueScan on my old MacBook Pro and was very happy with so I gave it a shot. Note that VueScan is not Open Source and not free but it is excellent software and well worth the €25 purchase price.

Lo and behold it found the scanner and it supported all of the scanner’s features.

  • Flatbed scanning
  • Auto feed
  • Duplex auto feed

However VueScan would only detect the scanner when run as root due to libusb permissions.

To add permissions for non root users to use the scanner I made the following changes. This guide should also be helpful when changing permissions for any USB device. The following changes were made on an Ubuntu 17.10 machine.

# Add myself to the scanner group. You can do this through the “Users and Groups” GUI too.

philroche@bomek:$ sudo usermod -a -G scanner philroche

# Find the scanner vendor id and product id

Running dmesg we can see the scanner listed with idVendor=04a7 and idProduct=04bf

philroche@bomek$ dmesg
usb 1-2.4.3: new high-speed USB device number 26 using xhci_hcd
usb 1-2.4.3: New USB device found, idVendor=04a7, idProduct=04bf
usb 1-2.4.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-2.4.3: Product: DM3220
usb 1-2.4.3: Manufacturer: Xerox
usb 1-2.4.3: SerialNumber: 3ASDHC0333

Note: The device number will most likley be different on your system.

Running lsusb we can see that the scanner is also listed as “Visioneer”

philroche@bomek:$ lsusb
Bus 001 Device 026: ID 04a7:04bf Visioneer

Note: As with the the device number, the Bus used is likley to be different on your system.

We can see above that the device is on bus 001 as device 026. Using this info we can get full udev (Dynamic device management) info.

philroche@bomek:$ udevadm info -a -p $(udevadm info -q path -n /dev/bus/usb/001/026)
looking at device '/devices/pci0000:00/0000:00:14.0/usb1/1-2/1-2.4/1-2.4.3':
 ATTR{bNumInterfaces}==" 1"
 ATTR{version}==" 2.00"

This is the info we need to create our udev rule

# Add Udev rules allowing non root users access to the scanner

Create a new udev rule

philroche@bomek:$ sudo nano /etc/udev/rules.d/71-xeroxdocument3220.rules

Paste the following text to that new file

SUBSYSTEM=="usb", ATTR{manufacturer}=="Xerox", ATTR{product}=="DM3220", ATTR{idVendor}=="04a7", ATTR{idProduct}=="04bf", MODE="0666", GROUP="scanner"

This adds a rule to allow any user in the “scanner” group (which we added ourselves to earlier) permission to use the usb device with vendor 04a7 and product 04bf.

Note you will have to log out and log in for any group changes to take effect or run su - $USER

# Reload the udev rules

philroche@bomek:$ sudo udevadm control --reload-rules

# Test these new udev rules

philroche@bomek:$ udevadm test $(udevadm info -q path -n /dev/bus/usb/001/026)

You shouldn’t see any permissions related errors.

Now when you run VueScan as a non-root user you should see no permissions errors.

# Start VueScan

philroche@bomek:$ ./vuescan


Creating a VPN server on AWS using PiVPN

One of the streaming services I use called NowTV recently launched an Irish service alongside their UK service which I was using. The Irish service costs _double_  the cost in UK. They have also begun geoblocking all Irish users and also users of VPN Services like ExpressVPN and PrivateInternetAccess from using the UK service.

To get around this I decided to set up my own VPN server on AWS in their London datacenter to get around the geoblocking.

The easiest way I have found to set up a VPN server is to use PiVPN ( which was designed for use on Raspberry Pi but can be installed on any Debian based machine.

There has been a few recent guides on how to install PiVPN but this one focusses on installing on AWS.

A prerequisite for this guide is that you have an AWS account. If this is your first time using AWS then you can avail of their free tier for the first year which means you could have the use of a reliable VPN server free for a whole year. You will also need an SSH keypair.

The steps are as follows:

  1. Start up an instance of Ubuntu Server on AWS in the London region
  2. Install PiVPN
  3. Download VPN configuration files for use locally

1. Start up an instance of Ubuntu Server on AWS in the London region

Log in to your AWS account and select the London region, also referred to as eu-west-1.

Selection_141 (copy).png

Create a new security group for use with your VPN server.


This new group sets up the firewall rules for our server and will allow only access to port 22 for SSH traffic and UDP port 1194 for all VPN traffic.


Launch a server instance


We will choose Ubuntu Server 16.04 as it is a Debian based distro so PiVPN will install.


Choose the t2.micro instance type. This is the instance type that is free tier elligible.


Leave instance details default


Leave storage as the default 8GB SSD


No need to add any tags


Choose the security group we previously created.


Review settings – nothing to change here.


Click Launch and specify either a new SSH keypair or an existing SSH key pair. I have chosen an existing pair which is called “philroche”.


Check the checkbox abount key access and click Launch Instances. Your instance will now launch.


Click View Instances and once state has changed to running note the IPv4 Public IP. You now have an instance on Ubuntu Server running on AWS in their London datacentre.


2. Install PiVPN

SSH in to your new server using the private key from the pair specified when launching the server.

ssh -i ~/.ssh/philroche ubuntu@%IPV4IPAddress%

substituting %IPV4IPAddress% for the IP address of your server


Once logged in update the packages on the server.

sudo apt-get update


Start the PiVPN installer.

curl -L | bash

For more detail on this, see


You are then guided through the process of installing all the required software and configuring the VPN server:





Choose the default ubuntu user.



We do want to enable unattended upgrades of security patches.


Choose UDP as the protocol to use.


Choose the default port 1194.



Create a 2048 bit encryption key.



Choose to use your servers public IP address.


Choose whichever DNS provider you would like to use. I chose Google.


Installation is now complete 🙂


Choose to reboot the server.



Once the server has rebooted, checking the AWS dashboard for it’s status, SSH back in to the server.

Now we need to configure a VPN profile that we can use to connect to the VPN server.

The easiest way to do this is to use the ​​​​pivpn command line utility.

pivpn add


This will guide you through the process of creating a profile. Make sure to use a strong password and note both the profile name and the password as you will need these later.


Set up is now complete so you can logout.


3. Download VPN configuration files for use locally

The only thing left to do is to download the profile you created from the server so that you can use it locally.

scp -i ~/.ssh/philroche ubuntu@%IPV4IPAddress%:/home/ubuntu/ovpns/%PROFILENAME%.ovpn .

substituting %IPV4IPAddress% for the IP address of your server and %PROFILENAME% with the name of the profile you created.

This will download the .ovpn file to your current directory.


Once downloaded you can import this to your VPN client software of choice.

I used the profile on a small Nexx WT3020 I had with OpenWRT installed. I connect this to my NowTV box so I can continue to use NowTV UK instead of the overpriced NowTV Ireland.


I hope this guide was helpful.