What is OpenStack?

OpenStack is a collection of programs that are used to create a cloud environment. The term “cloud computing” is used to refer to the decentralised calling up of programs and data. In a cloud, data is saved in several, sometimes physically distant locations. This requires an infrastructure that allows for decentralised access, in order to guarantee maximum security. Data which may be of a sensitive nature should not only be made highly available, but it should also be protected from unauthorised access and data loss.

Cloud solutions offer the unbeatable benefit of also functioning on connected devices with less powerful hardware components. The flexibly scalable computing power is in the cloud itself. All that is needed is a fast and stable internet connection, which makes setting up a complex network less expensive. There are no high purchase prices at all for the acquisition of hardware. The only costs incurred for working with a cloud solution are normally those related to the actual resources being used. It is also possible to operate a cloud environment on rented virtual servers, which also makes it interesting for small businesses and start-ups that cannot afford large IT expenses.

The OpenStack software pack includes all of the necessary components for creating a cloud environment. Despite being a relatively young project, it is still well-developed and secure. OpenStack was created in 2010 by the U.S. space agency NASA and the company Rackspace. NASA wanted software for its project-related work that would make it possible to create flexible and temporary computer networks. Since then, notable companies such as AT&T, RedHat, Canonical (the developer of Ubuntu), Intel, IBM, and Huawei have contributed to its development.

The software only runs on Linux operating systems, and was published with an Apache Licence. As such, the source code is openly available to anyone and the program can be used for free without any limitations. The 20th version of OpenStack was released in October 2019 under the name “Train.”

The OpenStack cloud is made up of several components, of which the most important are:

• Nova (compute service)
• Keystone (identity service)
• Glance (image service)
• Neutron (networking)
• Cinder (block storage)
• Swift (object storage)
• Horizon (dashboard)

Nova is the computing component of the OpenStack cloud and the first one with which OpenStack was launched in 2010. To some extent, it is its backbone, and it is responsible for the most important task: managing the virtual computer. Nova has been developed to the point that it can manage entire groups of virtual computers. Individual computers are synaptically connected to one another, and the number of nodes varies. To create virtual machines, Nova primarily uses the licence-free KVM hypervisors that are integrated into the Linux kernel, as well as XEN hypervisors that were created by the University of Cambridge.

Keystone is responsible for authentication and assigning permissions to users (identity). In cloud computing, not only individual PCs, but also entire networks are mapped. As such, user authentication and isolating partitions are very important. Keystone assigns individual access information to each of the cloud’s users (called “roles”) with very explicit rights.

Glance provides image services, meaning images of the data carriers of virtual machines. Glance can also secure and retrieve images. This makes it possible to create a sort of template library for required systems, which can then be generated in the network as often as desired. In addition, Glance ensures availability since the required machines can be reconstructed at any given time.

Neutron (formerly Quantum) provides the virtual network infrastructure of OpenStack. It can be used to divide sub-networks, manage IP addresses, and create virtual networks (VLANs) virtual networks (VLANs). Neutron also supports VPN (Virtual Private Networking). It enables data exchange among the components of OpenStack, for example, between individual virtual machines. Neutron also provides a firewall for the network.

Cinder is responsible for the provision of permanent memory in the form of block storage, like hard drives. Cinder does so through virtualisation. As such, the volume can be modified accordingly (scalability). Cinder block memory functions like a physical hard drive on a computer. Saving data is simple since Cinder makes a user’s hard drives available to them through centralised APIs, and it also has a snapshot function.

Swift is the object store. It can integrate distributed memory in which seemingly randomly distributed data objects can be used on connected drives. Redundancy will be created if needed since the objects can be physically stored multiple times. In addition, storage created by Swift can also be used by Cinder or Glance. It is also possible to use distributed object storage that has been generated by Ceph or GlusterFS as a substructure.

Horizon acts as the dashboard. In other words, Horizon is the graphic user interface through which the components in the OpenStack network can be managed. User management can also be managed in the process. The design and functionality of Horizon are customisable.

The OpenStack cloud is the software-based replica of an incredibly complex IT infrastructure. The modules that must normally exist physically are each virtually generated by one of the aforementioned components. Required memory is created by Swift, and then optionally made available as block storage through Cinder. The functionality of an individual server and computer within the network is generated and managed by Nova. The pool of available virtual machines is provided by Glance.

Neutron handles networking, as well as protection through a firewall and monitoring. Keystone manages the authentication and authorisation of users. Once the system has been built, it can be comfortably administered through Horizon. If more storage space or performance is needed for a short period, both of these factors can be adjusted correspondingly.

The OpenStack cloud offers the following advantages:

• Few prerequisites are needed to use it: Cloud services can be used on any device with internet access
• High data security and reliability
• Scalable storage volume and performance
• Cloud services enable collaboration
• Access is not limited by location
• High distribution and acceptance
• Uniform standards

Unfortunately, there are also certain disadvantages to using OpenStack:

• Highly-dynamic range of functions: OpenStack is an open and very dynamic cloud-computing solution. New functions are added regularly, but some other functions can also be removed.
• OpenStack does not offer any sort of organised support. A lot of documentation and helpful articles can be found online, but it can take quite a bit of time and effort to find the right ones. Unlike commercial solutions, there is no dedicated customer support.
• KVM and XEN are primarily supported as hypervisors, which can lead to problems when integrating other virtualisation solutions such as VMWare. For example, users report network problems when using VMWare along with OpenStack.

Due to the absence of a licence, using OpenStack is extremely inexpensive. Once the system has been set up, it can be easily managed. The use of virtual servers that include hosting services is already possible through a small cloud solution that costs £10 to £20 per month. That means OpenStack can be used as a platform for private cloud applications, for example, a bit like a Wiki. It can even be used to implement sideline projects or even start-up ideas, such as online shops.

OpenStack is an ideal option for SMBs to get started in the cloud-computing world, as well as for the transfer of data and applications. For example, it also offers the possibility of creating a public cloud. Rights management within the OpenStack cloud, in particular, offers a wide range of possibilities for optimally managing the collaboration of various user profiles.

Large companies can transfer parts of their network infrastructure, such as particularly sensitive data or programs, and also use OpenStack within the framework of a multi-cloud approach or use it as a component of a hybrid Cloud. The failure of application servers is lower as a result since servers can be replicated as often as desired. Data is made redundant in any case in the system, so that the loss of data through hardware damage is virtually impossible.

Anyone who would prefer not to use OpenStack can replicate the required services using virtual servers or online storage, for example. Using solutions such as Owncloud or Nextcloud is also possible.

Other similar solutions are:

• OpenNebula (free)
• VMWare (fee-based)
• Microsoft AzureStack (fee-based)
• Google Anthos (fee-based)

In addition, more and more companies are using the convenient option of using a service provider to set up and manage a cloud (managed cloud).

No matter what you decide, there are several good arguments for getting into cloud computing. When it comes to efficiency and flexibility, cloud computing is absolutely unbeatable. There is also the environmental factor to cloud computing that makes it favourable since the purchase of unnecessary hardware can be avoided or done without altogether.

But the most important factor is definitely the security of your data. It takes a lot of trust to place your own data or that of your clients into the hands of external service providers. As such, the effort of creating your own cloud with an established product like OpenStack can pay off very quickly.