Friday 27 April 2018

SSO from Chromebooks to Azure AD.

This post has been extended with an related article that references the Azure user interface for 2019 and also includes some tips and tricks gained from recent deployments.

You can find the new post here.


Following on from a recent post showing how to auto-provision users from Azure to Google G Suite it seems like a good idea to complete the picture by describing Single Sign-On (SSO) from Google to Azure AD. The idea is you can pick up a Chromebook and be presented with a Microsoft dialog rather than the standard Google login challenge.

Like the user provisioning example this procedure does not require local federation (ADFS) but relies on the equivalent cloud based service bundled with the Azure AD Free tier. Under this arrangement users can get SSO access for up to ten apps which is pretty generous as the whole of Google G Suite is considered to be a single app.

For this example we’ll use the, account that the Azure provisioning service created for us in the earlier blog. It follows that the domain must be configured in both Azure and Google and the user account logon name is the same on both systems.

The configuration setting for both auto provisioning and SSO can be found in the Azure Portal under Enterprise Apps.

Clicking in the New Application icon presents you with comprehensive list of SaaS applications that come with pre-built templates that allow them to integrate with Azure directory services. Again the best way of finding the right option is to simply search for “google apps”.

Choosing this option opens up a blade on the right that allows you to enter some basic config  details and name the service. Once you are back at the main menu you can configure SSO which turns out to be quite straightforward compared with working with ADFS.

From the drop menu select SAML-based Sign-on. This creates a whole range of input boxes.

The key fields are Sign on URL and Identifier which can be customized to suit your setup. The data below worked for me.

Sign on URL:


From here the default settings should suffice. Make sure that the User Identifier is set to user.userprincipalname.

In the SAML Signing Certificate section check the box Make certificate active and save the config. Download and store the certificate (*.crt) that’s created for you.

All that’s left to do is to collect some information and transfer this to Google, luckily Microsoft makes this pretty easy.  Clicking on the section below provides a simple tutorial on how to update Google G Suite.

The key information you need is conveniently listed in the Quick Reference section towards the bottom of the help dialog.

The values will be different for your Azure tenancy but you will need both URL’s and the certificate you downloaded earlier before heading off to the Google Admin console.

Configuring G Suite and Chromebooks for SSO.
Single Sign On  is managed under the Security icon within the Set up single sign-on (SSO) section.
One note of warning, currently its not possible to turn on SSO for a subset of Google users. Continuing down this route will  require all your non-admin G Suite users to authenticate with their Azure AD credentials

In the dialog shown above paste in the URL’s into the relevant fields  and upload the certificate. The Change password URL is standard for all configs:

If you encounter errors, try saving each entry in turn. In particular the certificate upload seems to work better as a single load and save action.

Optionally, check the Use a domain-specific issuer box to enable a domain-specific issuer. If you enable this feature, Google sends an issuer specific to your domain,, where is replaced with your actual domain name.

If you don't check the box to enable a domain-specific issuer when you set up SSO, Google sends the standard issuer, as recorded in the Identifier field in the Azure section above.

When you are ready, check-in the Setup SSO option but be aware this action will affect every account in your organisation. Unchecking the option turns off SSO without the removing all the data.

As a simple test, logging into the Chrome browser will now pass the request to Azure for authentication. Once you have that working you can prepare the Chromebooks to accept third party authentication by setting some some additional device and user policies.

In Chrome Management  - User settings search for "SAML". Enable SAML-based SSO and set the logon frequency.

In Chrome Management  - Device settings search for "SAML" again and allow users to go directly to the SAML SSO page.

So long as the user and device are within the scope of the new policies the chromebook will now present the Microsoft Azure login page instead of the standard Google dialog, which I must admit looks a little weird when you first see it.

Remember, authentication takes place against the Azure directory - so the user account needs to be in Azure with a matching account in Google to provide the user policies. Typing in a valid Google account without an Azure account won’t pass the test. In the same way trying to gain access using a valid Azure account that does not match an active G Suite account gives a Google error.

The whole process is pretty simple and allows Chromebook to authenticate against Azure AD (MS Office 365) without requiring local servers and the complexity of ADFS.

However the big advantage of running  federation services in the cloud is fault tolerance.  Creating a highly available cluster to support a tier one component like authentication is not something schools should be doing anymore.  Federation is just a cloud service like everything else, you might as well make use of it.

So can you do it the other way round and use the Google SAML federation services to answer for Azure logins?   Surprisingly yes.

It's now possible, under specific circumstances to logon to Windows using a G Suite account.

Thursday 5 April 2018

How to drop Windows apps on a Chromebook.

Here’s something to consider over a coffee: What does a Microsoft Windows computer actually do?

Since the majority of school computers in the UK run Windows and a lot of time and money is spent keeping those devices working you would hope it’s something pretty important.

Perhaps it’s keeping all of your files and data safe ?

That’s true but security and file storage is actually managed by the backroom server while file management is a standard feature of every mainstream operating system, just like printing and browsing the web. These are important functions but any desktop (or mobile) operating system could fulfil those roles. So what’s the answer ?

The fact is, you need a Windows computer to run Windows programs.

All the other stuff like virus protection, security patching, backup and all the fancy user interface features and dialogs just allow the operating system to run Windows programs in a secure and predictable manner.

It’s been a long time since the Windows operating system  itself added anything useful to the user experience (Minesweeper?). In fact the main challenge for the school administrator is to lock-down the desktop to ensure users have as little contact as possible with the underlying feature set.

I suspect the ideal configuration for a Windows desktop in schools would be a template of shortcuts linked to the main productivity apps with some additional icons for logging off and rebooting.

Even with this minimalist approach the network admin still has to deploy and update each application while making sure an installation of one application doesn't break all the others as well patching the underlying OS.

Over the last decade there have been multiple attempts to fix this problem including terminal services and VDI but in many respects they only make the problem worse. You have to add additional server hardware, manage even more instances of the operating system and, after all that effort, the local desktop doesn't even get the chance to do the one thing it's good at - which is running Windows programs.

Let’s be honest if you were starting from scratch you’d think of a better way of doing this.

So lets kick the bucket and think about what that alternative might look like might look like.

The local device would be lightweight, easily managed, simple to licence, fundamentally secure, self maintaining and provide the base functions of file management, print and web browsing.   The system should start quickly, present a security challenge and then simply act as a platform to launch the apps that you need to do your work done. In many respects you are describing Google’s Chrome OS, the operating system that runs on a Chromebook.

Alternatively this imaginary device could be running Windows 10 S mode which is basically a Windows 10 Pro with a simplified, locked-down configuration which also meets some of the criteria listed above,

Unfortunately the one feature that both operating systems lack is the ability to run the type of legacy Windows program that education uses on a day to day basis. Chrome OS is a non-starter for this purpose and in order to run a local copy of SmartNotebook or a specialised STEM program on Windows 10 S you have to upgrade to the Windows 10 Pro edition which takes us back to where we started.

On the face of it the problem seems unsolvable but there may be a solution on the horizon.

Purchase a Chromebook today and it can run any Android app from the Google Play Store. The Android Skype app knows nothing about Chrome OS and believes it’s running on fully featured Android stack (V6.0 Marshmallow).  In fact it’s a clever trick that makes use of technology commonly described as containers.

Containers allow the underlying OS to present itself in different ways to processes that it’s hosting. The idea is similar to machine virtualization but in this case it not the hardware that virtualized but the operating system kernel and for this reason is very lightweight and carries few additional overheads. This is how a Chromebook with only 4GB of memory can appear to run two operating systems at the same time. Another important feature of a container is that it ensures the isolation of the running processes which means it’s very secure.

So if containers can represent an Android run-time environment what else can they do?

Recent articles suggest that Chromebooks will soon have the ability to present Linux as a container which means that schools could safely access a range of open-source software rich in code development and media editing titles.

Which leads to the final point - could Chromebooks run a Windows application in a container?

The answer appears to be a qualified yes.
Recently Droplet technology announced a deployment package that can do just this. The hosted applications behaves exactly as it would if it were running in on a Windows operating system  - because it is.

All the technology runs locally and works without an active internet connection.  It’s not an emulation or a graphical offload, the application runs natively and is responsive and fully featured.

But let’s bring the conversation back to reality. If you have a school whose curriculum is based heavily on MS Office and locally installed Windows applications then your future is best served by the toolset provided by Microsoft.

But for schools moving towards SaaS the technical direction is often blocked by a dozen or so Windows programs that are central  to the curriculum. This is a problem that a container technology like Droplet could easily solve.

Eventually containers could be used to deploy applications across a range of OS types (including Windows) creating a true ‘run anywhere’ solution that doesn’t require a mass of backend server hardware.

There are still a number of problems to overcome, mainly around managing resources on a shared deployment but the future of local applications lies with containers. It’s a proven technology that underpins most cloud services and its about to make a splash in the mainstream market.