What is Containerization?
Out of every ten applications, at least eight need to be hosted on another service provider’s infrastructure. The two most common techniques used for hosting these applications are virtualization and containerization. While both techniques have the same purpose, they have notable differences. Understanding their differences is crucial for every organization to choose the best hosting technique.
Containerization is the process of simulating a system’s OS only, according to the hosting requirements of the concerned application. There is no need to install different operating systems for different machines. Every container system needs to follow a certain architecture level, with each slab set via a hierarchical method.
Table of Contents
- The bottom layer comprises hardware units like disk storage, PC, CPU, and several networking interfaces.
- In the second layer, you will find the kernel OS, whose main function is to bridge the gap between software and hardware.
- Above the host OS layer is the slab of guest OS and the main container engine.
- The top layer comprises libraries of each application meant to run on the OS.
Advantages of Containerization
- There is no need to write different code versions for various virtual machines.
- With containerization, you can reduce redundancies and overheads
- To streamline DevOps, the best hosting method is containerization.
- With the help of containerization, you will be able to deploy the codes faster into the prod environment.
- As the application stays isolated from hardware, containerization ensures a higher security level.
Disadvantages of Containerization
- Containers designed for different operating systems need a concerned hosting provider.
- If multiple machines use the same OS, security concerns can arise.
What is Virtualization?
Virtualization is the primitive hosting technology that simulates the entire hardware machine, including the CPU, networking routes, and OS. A single server is used for hosting multiple applications. However, developers need to optimize the app codes accordingly if different servers are used.
Several types of virtualizations act differently and allow you to run the applications with ease. These are:
i. Server virtualization
ii. OS virtualization
iii. Data virtualization
iv. Hardware virtualization
Advantages of Virtualization
- With the help of virtualization, you can easily cut down the IT costs.
- It helps in business continuity because the applications are hosted on virtual environments that can be switched from one server.
- Virtualization can enhance both the productivity and efficiency of your enterprise operations.
- With this technique, apps are hosted with no security concerns.
- As the application stays isolated from hardware, containerization ensures a higher security level.
Disadvantages of Virtualization
- Virtualization will require different code versions to be processed on several machines having different OS.
- When virtual machines need to be moved from one data center to another, the task is more challenging.
Containerization VS Virtualization
| Attribute | Virtualization | Containerization |
|---|---|---|
| Containerization | Separate OS with 100% functional and technical independence | User-mode OS with storage for required software codes only |
| Isolation | Completely isolates the software from the host OS and virtual machines | Completely isolates the software from the host OS and virtual machines |
| User compatibility | It can run on any OS within the virtual machine | Runs only on the host OS |
| Persistent storage | Virtual Hard Disk: Single VM Server Message Block: Shared VMs | Local disks: Single node SMB: Shared servers and nodes. |
| Deployment | Hypervisor software is used to deploy a single virtual machine | When a single container has to be deployed, Docker is preferred the most. For multiple container deployment, orchestrators like Kubernetes are used. |
| Networking | It depends on the entire VNA. | Only an isolated view of a VNA is preferred. |
| Load balancing | The virtual machines are compiled on numerous servers during a failover cluster. | The containers can automatically function on the cluster node without any external influence. |
1. Operating System
Every virtual machine stores the entire operating system, including the application, its libraries, dependencies, server, and virtual copies of the hardware units. As a result, different OS can be run in virtualization without making any further changes. However, due to the presence of other OS, components will be irrelevant to the software to be deployed.
On the contrary, a container only contains the specific host OS, the application, and its dependencies and libraries. It is much more particular and isolates all types of resources for deploying the software.
2. Isolation
Containers depend on the host OS to provide isolation for the applications to run on the servers. As a result, they can only service isolation, thereby limiting resource access. On the contrary, a virtual machine implements a hypervisor to provide full-scale isolation to the application. Therefore, it offers better functionality for application deployment than containers.
3. User Compatibility
Virtualization provides better access to different operating systems apart from the host OS, which is why it is often used in deploying various applications. On the other hand, containers only contain the specific version of the host OS. Therefore, these are used for deploying particular functionalities of the concerned application.
4. Persistent Storage
Most containers start and stop the functions automatically, while virtual machines require an external operator. However, persistent storage is needed to ensure data and servers are available. A virtual hard disk is used to store all the data for a single VM, while a local storage unit is enough for a container working on a single node. SMB or Server Message Block is used for both VMs and containers when multiple or shared servers need to be handled.
5. Deployment
When deployment is considered, containerization offers greater flexibility since it requires creating an image of the application and deploying it to the required server. On the other hand, when a VM is used to deploy the software, configuration is required, followed by installing the app on the target OS and publishing the same to the concerned platform.
6. Networking
Since containers share the firewall of the host OS, it needs only the isolated view of a virtual network adapter to deploy the application. However, virtual machines depend on the complete VNA to deploy the application.
7. Load Balancing
When there is a change in the incoming load, the virtual machines need to be moved to other nodes to satisfy the failover cluster requirements. On the contrary, the containers can automatically function on the cluster node without any external influence.
Containerization VS Virtualization: Which is the better way to deploy an application?
Containers and virtual machines are both used to host and deploy different applications. However, containers are a better option for running multiple software units on a limited number of servers. When a monolithic workload is considered, the VMs are more feasible since they can run more applications with diverse server requirements.
