License Challenges — Containers v Virtual Machines
Containers are simplified virtual machine (VM) Images where the App is separated from the Kernel. This means that Containers do not contain operating system images which makes them more lightweight and portable.
Containers have many benefits to an organisation such as;
· They require less system resources.
· Due to the portability of Containers they can be easily deployed to multiple OS and hardware platforms.
· They are easier to manage, i.e. they can be easily deployed, patched, and scaled due to their portability.
· They can be used to increase resource utilisation of servers because multiple Containers can be deployed on the same machine.
As beneficial as Containers are to businesses they herald a change to the traditional way of deploying applications and this in turn poses new challenges for license management. As a part of any Cloud migration strategy, time should be taken to evaluate the benefits of leveraging containers instead of VMs as a way to improve performance and reduce cost.
Much like software licensing in any environment, ongoing and proactive management is important to complying with license policies. My post will include a quick overview of Containers v Virtual Machines and then take you through some of the license challenges to watch out for.
How are Containers different from Virtual Machines (VMs)?
Containers and VMs are simply different ways of achieving virtualisation. Virtual Machines are basically hardware level virtualisation because the virtualisation starts at a hardware level. We start with the hardware and the virtualisation is enabled by the hypervisor. The diagram below provides an illustration of the setup of a basic VM.
Containers are considered operating system level virtualisation as you will see below. The virtualisation happens at one level higher than the hardware level virtualisation.
In both instances the aim is to achieve isolation of machines. For VMs we are splitting the system resources across VMs that are relatively independent of each other whereas with Containers we are dealing with process isolation. Unlike VMs, Containers are sharing the same operating system and the same kernel.
Terminology
There are some key terms to be familiar with when discussing Containers;
1. Container Runtime Environments: these are software technologies that enable Containers to run on a computer. The most used/popular Container runtime environment is Docker.
2. Container Orchestration Platforms: these are tools used to automate the deployment, management, scaling and networking of Containers. The market leaders for Container Orchestration tools are Kubernetes (K8) and OpenShift.
3. Container Registries: this is a repository or a collection of repositories used to store, distribute and access Container Images.
Containers and Software Licensing
Depending on the software and license metric imposed Containers may have no impact, some impact or significant impact on license management. As with all software licenses, active management is important. The following will require extra attention;
· User based licenses — if an application is containerised and multiple Containers are created, essentially the same application duplicated multiple times, every use/access of that application on all Containers will need to add up to the sum of, or below the licensed quantity. This is particularly true for concurrent licenses and total users’ licenses.
· Metered/Consumption based licenses — using the same example above and depending on the type of measurement criteria, if an application is duplicated using Containers, the use of the application may also increase.
The challenges Containers pose for ITAM professionals revolves around the following;
· Staying abreast of licensing terms and conditions that govern the use of the software they are using.
· Reporting: How are Containers reported within your organisation? Not every SAM tool will provide you with the visibility of the software that is running on Containers.
· Metering: how will license restrictions be enforced and metered.
· Processes: due to the agility of Containers, they can be deployed quickly and this might mean they by-pass processes that may require significant approvals and keep them on the ITAM manager’s radar.
Summary
Containerisation offers significant benefits such as portability, efficiency, agility and flexibility to name but a few however they also pose challenges to the ITAM manager. These challenges are not insurmountable but require sharpened processes to curtail unknown deployments (shadow IT) and increased vigilance to ensure that software license restrictions are not breached either by excessive or improper use.
Further Information
As independent enterprise vendor license experts, we have deep expertise in the application and management of a wide range of vendors including Microsoft, Oracle and IBM and can advise and guide on any license queries you may have.
Please go to our website or contact us with any questions.
