Serverless Architecture: Overview of Serverless Computing

Every developer strives to speed up product development while maintaining enough flexibility and confident control over the process. Microservices application architecture helps solve these tasks and, over the past 10 years, has begun actively competing with the traditional monolithic approach. To begin, let’s look at the difference between them. Microservices Architecture vs. Monolith The difference between these two software development approaches is easiest to illustrate with an example. Let’s imagine two online stores: one implemented as a monolith and the other as microservices. A monolithic online store is a single, indivisible structure that combines all components: databases (catalog, customer data), shopping cart, order and payment forms. All of these elements are tightly interconnected and located on the same server. In a microservices system, each component is an independent module that developers can work on separately. And naturally, nothing requires hosting these modules on a single server. Thus, microservices architecture is a kind of constructor that allows you to add new elements painlessly as you scale the application. A monolith, on the other hand, can be compared to a solid wall: scaling here is only possible by adding another identical monolith. It’s worth adding that microservices are sometimes mistakenly perceived as a set of very small services. This is not the case: for example, the database of a large online store may contain millions of records and occupy tens of gigabytes, yet still be just one of the modules within the microservices architecture of the whole application. Comparing Microservices and Monoliths by Key Criteria Now let’s look at the main characteristics of microservices technology in comparison with a monolith and see how both approaches solve the same developer tasks. Release Cycles Development speed and frequency of updates increase with microservices thanks to modularity: changes are made not to the entire codebase but to individual modules. With a monolith, however, the whole platform must be updated first, which increases testing and debugging time. As a result, development slows down and updates are released less frequently. Technology Stack The microservices model offers significantly greater flexibility because each service can be written in its own programming language and may use different libraries and data-storage technologies. With a monolith, the situation is different: changing the technology stack is nearly impossible. Developers are forced to stick to the initial tools. Developer Onboarding Each module in a microservices architecture is self-contained, making it possible to bring in programmers who are familiar with the functionality of a specific service. This substantially lowers the onboarding threshold. With a monolith, new developers must dive into the code of the entire application, understand the functions of every block, and only then begin productive work. Thus, maintaining a monolith is more dependent on specific team members. Optimization Characteristics The modularity of microservices architecture also positively affects optimization, since developers can optimize each service separately. Optimizing a monolithic structure is more difficult because the team must account for links between indivisible blocks, and updating any one of them inevitably affects the entire application. Application Scalability The distributed structure of microservices and their ability to run on separate servers make scaling fast and easy. In monoliths, scaling one component inevitably requires scaling the entire application as a whole. Fault Tolerance Because services are hosted on different servers and have a modular structure, microservices architecture achieves independence of each module. This significantly increases system resilience: a failure in one service does not cause the entire application to fail. With a monolith, the situation is different: all components are tightly interconnected, so the failure of one module can make the entire application inoperable. Do I Need to Switch to Microservices Right Now? As we’ve seen, microservices have advantages in many key areas. But does this mean you need to abandon monoliths as an outdated approach and immediately switch to microservices? The answer depends on the current state of your project. And let’s say right away: rushing to adopt microservices is not always the right choice. Distributed architecture also has its drawbacks. First, microservices require ensuring network connectivity between modules. If a network connection is unstable, this leads to delays and data inconsistencies, which create potential problems in application behavior. Second, each module of a microservices system requires separate testing and health monitoring. Additionally, you will need to allocate cloud resources for each module, which may increase costs. Third, with the microservices approach, teams responsible for different modules may encounter interaction issues. This means you may need a connecting link in the form of DevOps specialists who can streamline collaboration and speed up development. All the factors listed above allow us to conclude that the transition to microservices must be timely. Usually, during the early stages of a project, this is unnecessary, especially if developers have limited human or financial resources. Switching to a microservices architecture makes sense when there is a clear need for significant scaling, and scaling a monolith has already become difficult. Microservices may be right for you if: You have a large team. In this case, it makes sense to divide the team into separate, independent groups, each responsible for its own service; You have a complex, branched application. In this case, it’s far more convenient to update and maintain modules separately than to rebalance the entire system each time; Your application traffic is highly variable. For example, you see sharp spikes in load during certain periods. Microservices' distributed structure allows quick scaling during peak loads, after which you can easily return to normal capacity levels; Your application is frequently updated. Working with separate modules in this scenario is much simpler, and new releases will be significantly faster. If your project meets at least one of these criteria, this is a reason to consider breaking it into independent elements. However, if your application is relatively small and does not require frequent updates, it is reasonable not to rush away from monolithic architecture. Useful Tools for Organizing Microservices A modern development approach requires a containerization platform. In most cases, developers use Docker for these purposes. Docker tools allow them to isolate the application from the infrastructure, meaning they can work with it equally well locally or in the cloud, which is very convenient for development. Once containers become numerous, an orchestrator becomes essential for managing and organizing groups of containers. Kubernetes is most commonly used as an orchestrator due to its strong compatibility with Docker. Another necessary tool is a load balancer, which ensures even distribution of network traffic across all cloud resources. This significantly increases the application’s fault tolerance.

A cloud hosting provider is a company that offers users virtual resources for remote infrastructure management and application deployment. Unlike traditional web hosting, cloud-based service providers allow for flexible configuration of rented resources, helping clients save on hardware, software, and system administration costs. In this article, we’ll review the key factors to consider when choosing a cloud hosting provider, starting with the core services these companies offer. Provided Services There are three main service models that cloud hosting companies typically offer. Ideally, a reliable provider should support all three: IaaS (Infrastructure as a Service): Basic infrastructure resources such as virtual servers, networks, and storage. PaaS (Platform as a Service): Software platforms for various tasks: database management, big data analytics, containerized app development, machine learning systems, and more. SaaS (Software as a Service): Fully managed software solutions that run on the provider’s infrastructure, reducing the load on the client’s computer or mobile device. Key features offered by best cloud providers include: A firewall to protect against DDoS attacks and malware. Automated backups with redundant data storage across multiple locations for disaster recovery. Data encryption to ensure confidentiality; even provider staff cannot access your information. Pricing When evaluating pricing, focus not just on the base rate but on what’s included in the package. Some providers attract customers with low prices, but cheaper plans often come with limited resources or features. For instance: Low-cost plans may not suit clients who handle large data volumes due to disk space limits or slow storage performance. Some providers may offer a “cheap” cloud server but fail to mention that your virtual resources are shared with other clients, reducing performance. Keep in mind: a high-performance server cannot be truly cheap. Company Experience As a rule, the longer a provider has been in the cloud hosting  business, the more reliable it tends to be. However, reputation also matters: look for verified online reviews rather than marketing claims. If a provider has been operating for over 5 years and maintains a solid reputation, it’s usually a trustworthy choice. A broad range of services is also a good indicator of expertise. Certification and Standards A strong advantage is certification under ISO 27001, the international standard for information security management. While not legally required, it shows that the company has a well-structured approach to security: defined access levels, regular internal and external audits, and continuous process improvement. Free Trial Period A trial period can significantly influence a provider’s credibility. If a provider offers 5–10 days (not just a day or two) for testing, it’s a positive sign that they’re confident in the quality of their services. Hardware Pay attention to the performance of CPUs and disk subsystems. Ideally, a provider should offer configurations for different needs, from entry-level setups to high-performance solutions using modern server-grade processors and NVMe drives, which significantly outperform traditional SSDs in speed and reliability. Reliability and SLA A reliable provider must guarantee service uptime in its Service Level Agreement (SLA), typically expressed as a minimum annual availability percentage. The SLA should also guarantee that you receive the computing power and software specified in your plan and that you can modify configurations, add or remove resources, and perform other key management tasks. Data Center Location Providers often advertise the geographic location of their servers as an advantage, but the data center’s certification level is far more important. Look for certification under Tier III, which represents the optimal reliability level (Tier I being the lowest and Tier IV the highest and most expensive). Tier III data centers can perform maintenance without downtime thanks to redundant infrastructure components. Technical Support The quality of technical support is a key differentiator. Pay attention to: Response time. It should be clearly stated in your contract. Willingness to help with tasks like auditing or migrating infrastructure from other services. Professionalism and courtesy—hallmarks of a customer-oriented provider. Contract Termination Even with the best cloud hosting provider, circumstances may change. Before signing up, check: How and when you can retrieve your data. How the provider destroys virtual machines and ensures complete data deletion upon termination. Checklist: Choosing a Cloud Hosting Provider Before making your decision, verify that your provider offers: Support for IaaS, PaaS, and SaaS models with additional features. Flexible, well-priced service packages. 5+ years of experience in the market. (Optional) ISO 27001 certification. A 5–10 day trial period for testing. Multiple hardware configurations with scalable performance. SLA-backed uptime guarantees and resource reliability. A Tier III–certified data center. Qualified, responsive technical support. A secure and transparent contract termination process.

When setting up a virtual server, an important decision is choosing the best server OS for your tasks. The operating system will largely determine the server's overall functionality and affect its performance and security. In this article, we'll examine several available options and discuss the advantages and disadvantages of each so you can make an informed choice. How Operating System Choice Affects Your Server Let's define the list of factors that the hosting operating system influences: Performance An operating system is software that manages hardware and provides an interface for interacting with it. Like any software, the operating system consumes part of the computing resources. For example, Windows Server will consume more than Ubuntu Server due to factors like the graphical interface. Before installing a particular operating system, determine whether you need the services and functionality it provides. A graphical interface won't affect web server functionality at all. Are you willing to spend additional resources on more comfortable administration? Compatibility In general, most software will be available to both Linux and Windows users. Developers are interested in having versions for different operating systems. Even some Microsoft applications, which theoretically should be interested in promoting their operating systems, run on Linux—for example, MS SQL databases. But, of course, not all Microsoft software can be run on Linux. For Windows, there's a special software layer that allows running Linux applications—WSL. If a Windows port of the application doesn't exist, WSL will help run it. Both Windows and Linux allow users to perform most work tasks. Compatibility affects administration convenience and performance. For example, PHP is available on both operating systems, but on Linux it runs faster. And running some applications will require additional effort. Cases where technology is only available on one operating system are rather exceptions. For example, if a company needs a terminal server or Active Directory, they'll have to use Windows Server. Licensing Almost all Linux distributions are distributed free of charge, while you'll have to pay for Windows Server and additional components. Security What's more secure: Windows or Linux? This is quite a debatable question. In general, each operating system has a sufficient number of information security tools available. System security primarily depends on the user. You can catch a virus on both Windows and Linux. But the probability of catching a virus on Windows is higher, simply because most viruses target Windows systems. Windows Server Virtual Servers Windows is one of the most popular operating systems. In 2008, Microsoft released a special version for virtual servers—Windows Server. Windows Server offers high performance, a rich set of features, and broad compatibility with other software and services. However, it can be more expensive in terms of licensing. Windows Server has many different versions, each with its own features and areas of application. Depending on the Windows Server version, additional functionality may be available to the user. For example, cloud infrastructure support, improved resource management and security, and tools for easier server management and monitoring. Depending on the specific business needs and constraints, one of the Windows Server versions may be better suited for use on a virtual server. Advantages of Windows Server Ease of use. Windows Server has a familiar and understandable interface that's easy to learn. Compatibility. Windows operating systems are very widespread, and many applications have versions specifically for them. For working with applications that don't have a special Windows version, WSL exists. Support. Windows Server has extended support from Microsoft, which means the server will receive updates for a long time. Integration with other Microsoft products. Windows Server easily integrates with other Microsoft products, such as Active Directory, Exchange, and SharePoint. Disadvantages of Windows Server Complexity of hosting websites. When working on Windows, as with any other operating system, you can host websites, but it will be more complex. Licensing cost. Many solutions that are free to use on Linux require paid licenses on Windows Server. Security vulnerabilities. Many viruses target Windows operating systems specifically, which increases the risk of server infection. Hardware requirements. Windows Server is quite demanding on hardware, and versions newer than Windows Server 2008 don't support 32-bit architecture. Virtual servers are mainly used by companies and enterprises, not private individuals. For them, the question of benefit stands above the convenience of a familiar interface. Therefore, using Windows Server as a server operating system is usually the exception rather than the rule. For example, Windows Server is used to implement remote desktops and terminal servers. Linux Virtual Servers The Linux kernel is the heart of the Linux family operating system. It's a set of software that provides basic functions: memory management, filesystem operations, and communication with hardware. The Linux kernel provides the connection between software and computer hardware, allowing programs to interact with computer resources. It also provides mechanisms for multitasking, allowing multiple programs to run simultaneously and ensuring their security. Linux operating systems are various Linux distributions that have their own features and toolsets. Each distribution is suitable as an operating system for a server, but they are usually used for different purposes: Ubuntu is used as a desktop OS, Debian as a base for other distributions, Kali Linux for network security, and distributions like Rocky Linux or AlmaLinux for server tasks. Next, we'll look at some of these systems and talk about what tasks they should be used for as operating systems for VPS/VDS. Advantages of Linux systems: Reliability Free software Configuration flexibility Compatibility with many hardware platforms Low resource requirements Large selection of shells Disadvantages: Administration complexity Limited application support Unfamiliar interface Absence of some popular applications Debian Debian is an operating system based on the Linux kernel and freely distributed under the GNU GPL license. Debian is one of the most stable and reliable Linux distributions and supports a large number of processor architectures, including x86, x86-64, ARM, MIPS, and PowerPC. Debian has a package manager mechanism that allows easy installation and updating of software, as well as creating backups and restoring the system. Debian also has a configuration management system that allows easy system setup and administration. For server tasks, Debian provides stability and long-term support, which are necessary for reliable long-term server operation. It also has many tools for server monitoring and management, as well as an extensive support community for problem-solving. Ubuntu Ubuntu Server is one of the Debian-based distributions used in server environments. It's the familiar Ubuntu OS to many, but without a graphical interface. Interaction is carried out through the terminal. Ubuntu Server offers a high degree of stability and reliability, as well as extended system management and configuration capabilities. It also has an apt package manager, which makes it easy to install and update software. Ubuntu Server is used for deploying web servers, databases, network equipment, cloud services, and much more. It also supports virtualization and is used as a guest OS in virtualization environments such as VMware and VirtualBox. Kali Linux Kali Linux is a Linux distribution specializing in information security and penetration testing tools. It's based on Debian and has over 600 tools for conducting security tests. If you plan to work in information security, then Kali Linux is ideal for this task. In addition, Kali Linux is also used for information security training and practicing skills in this area. However, it should be kept in mind that some tools in Kali Linux may be illegal or unethical in some countries and jurisdictions, and their use may violate laws and regulations. Therefore, before using Kali Linux, you need to ensure that you're acting in accordance with applicable law. Rocky Linux and AlmaLinux Note: CentOS, which was previously popular for server tasks, ended its traditional support model in 2021. CentOS Stream became a rolling-release distribution that serves as an upstream development platform for Red Hat Enterprise Linux (RHEL), making it less suitable for production servers that require stability. As a result, the community created two enterprise-grade alternatives that continue the legacy of CentOS: Rocky Linux and AlmaLinux. Rocky Linux and AlmaLinux are free, open-source distributions created as direct replacements for CentOS. Both are built from RHEL sources and offer long-term support and stability, maintaining binary compatibility with RHEL. One of the main advantages of these distributions is that they provide proven and reliable software and security and stability updates. They also have the dnf package manager (evolution of yum), which allows easy installation and updating of software. As server operating systems, Rocky Linux and AlmaLinux are used for deploying web servers, databases, network equipment, and various services. They're also suitable for use in virtualized environments such as VMware and VirtualBox. Which Linux System to Choose If you don't plan to use your server for high-load tasks, then Ubuntu or another desktop Debian distribution with a friendly interface will suit you, in which you'll be comfortable working. If we're talking about using a server in commerce with high load, then choose Rocky Linux or AlmaLinux. These operating systems are oriented toward use in such conditions. If you want to work in information security, then choose Kali Linux. Conclusion In this article, we examined the main operating system options for a virtual server. Each has its own advantages, disadvantages, and areas of application. Still, it's important to remember that the listed operating systems, in most cases, provide a decent level of performance and operability.