Monday 2 January 2017

Why moving servers to the cloud doesn't work.

It's a safe bet that 2017 will see increasing levels of hype around the adoption of cloud services for both business and education.

In the UK, schools are being encouraged to move in this direction by policy guidelines  issued by the Department of Education while at the same time licence changes from Microsoft are aimed at making MS Azure more attractive when compared with the on-site options.

Throughout the year Google will continue to work actively in this arena, promoting their cloud service (G Suite for Education and Google Classroom) as well as other initiatives such as Expeditions. At the BETT show, to be held in London later this month its likely that the vast majority of new software will be launched as cloud based applications (SaaS) rather than local server installs. It all appears to be heading in one direction.

Building a new school using cloud services is one challenge but migrating an existing school raises a whole range of issues. Most sites have long standing dependencies on locally installed software and legacy systems for both administration and teaching which makes this a far more difficult task.
Faced with this scenario it's tempting to simply take the existing server estate and replicate to an IaaS platform like Microsoft Azure.

Job done, your school is in the cloud with all the boxes ticked.

Because many school servers already run on virtualized server platforms such as Microsoft Hyper-V or VMWare this seems like a low risk solution and in some respects it is but it comes with one major drawback - it doesn’t work.

This is not a particular shortcoming of MS Azure but more a set of constraints that you face when moving workloads to Infrastructure As A Service (IaaS) by simply replicating the onsite architecture.

This might come as a bit of a surprise. Isn’t the whole point of the blog an attempt to reduce the number of on-premise servers and move to the cloud. It’s The Serverless School after all  - so what's going on.

Why wouldn't rebuilding the onsite infrastructure in the cloud bring the benefits we expect ?

It doesn't change anything.
Migrating servers to the cloud is not a catalyst for change. The servers are off site but same problems remain. Some pinch points are removed such as remote access, expansion capacity and the hardware upgrade cycle but you are still managing services in a similar way and it’s pretty much the same system.

Shifting to the cloud without anybody noticing it's a significant technical achievement but for a school it just represents a missed opportunity. Moving systems to an IaaS platform is not a transformative process.

Its slowww.
Actually users will notice a change - it’s going to be slower. Placing servers on the end of a wire that carries less than 10% of the throughput of a local connection is going to have an impact. SaaS applications don’t have the same problem because they have been designed to perform on low-bandwidth internet connection. In contrast the user experience provided by a locally installed application when accessing files or loading user profiles relies heavily on a responsive data connection and when this doesn't exist the results can be ugly.

The bill please.
Onsite servers are very inefficient. In most schools they are only used for about eight hours and even when they are working, utilise only a fraction of the total capacity. Throughout the whole day they’ll be consuming energy to heat them up and more energy to cool them down. They also require support, backup systems, redundant capacity and every five years they’ll need replacing. Migrating servers to an IaaS platform seems an obvious solution. So you rebuild or migrate your servers to IaaS and all it well... and then you get the monthly invoice.
OMG - why is it so expensive ?
IaaS appears costly because it’s measured against a misleadingly low value for on-site computing. On premise always looks cheap because most of the costs are hidden, unrecognised or simply not taken into account.

When you move your server estate to IaaS you see the true cost of under utilising processing power and storage and it can be quite a shock. IaaS is a great deal if your servers are working 24/7 to provide a service but if you export your inefficiencies to the cloud you simply get stuck with a checkbill for doing nothing.

There are workarounds some of these problems of course.

You can rationalise the number of servers and consolidate some of the services onto a single image.
"You started with six virtual servers but after the VLE install, the backup upgrade, the reporting software and the other stuff you 'need' you now have twelve although you’re not sure what they all do."
You could introduce some scheduling software in order to keep the cost down as well as keeping some of the core services local to speed things up, but now you have two systems, one on-site and one in the cloud and you're sure whether you have halved your problem or doubled it.

By the time you’ve re-engineered everything to make it work in the same way as it did on-premise wouldn’t it be simpler to consider a SaaS based solution.

Other considerations when moving VM infrastructure to the Cloud
Serverless School Serverless Serverless

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