Docker vs Virtual Machines
When it comes to Continuous Integration and Continuous Delivery (CI CD), choosing the right technology stack will decide the success of your deployment strategy. With multiple choices like Docker and Virtual Machines (VM), it is hard to figure out which one is better for your project. In this blog post, we'll break down the differences between Docker and VMs and provide a clearer idea of which approach may be better suited for your project.
Virtual Machines
Virtual Machines are an emulation of a physical computer system that allows multiple operating systems to run on a host computer. Each VM provides a complete environment that includes all the necessary resources like CPU, memory, storage, and network interfaces. Virtualization technology enables multiple virtual machines to run on a single physical machine concurrently, which can support virtualization of the latest hardware.
Pros of Virtual Machines
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Isolation: Each virtual machine runs as an individual system, and resources get assigned to that particular machine, which prevents other VMs from affecting the performance.
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Familiarity: VMs are easy to understand as they work like a physical machine.
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Security: VMs provide a unique security level by isolating resources, making it difficult to penetrate the system.
Cons of Virtual Machines
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Resource consumption: One of the biggest issues with VMs is resource consumption. Each VM requires its resources to operate, which can be costly in terms of memory consumption.
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Speed: VMs are slower than Docker containers because each VM has to boot up.
Docker
Docker is a containerization platform that allows software to run in a lightweight, portable container. Each Docker container shares the kernel of the host operating system and utilizes its resources, making them more efficient than the traditional Virtual Machines. Docker is perceived to be more modern which makes it a popular choice among developers for CI/CD.
Pros of Docker
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Resource optimization: Docker containers use fewer resources than VMs and take less time to deploy.
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Portability: Docker containers provide portability, allowing them to run on any platform, ensuring consistency in the application environment.
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Time-effective: Docker makes it easy to deploy your applications much faster than traditional VMs.
Cons of Docker
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Lack of Isolation: Docker containers share kernels, and containers may impact the performance of others.
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Security: Docker's nature makes it more susceptible to attacker exploits as the containers share the same kernel.
Comparison of Docker and Virtual Machines
| Metric | Docker | Virtual Machines |
|---|---|---|
| Resource consumption | Lower | Higher |
| Portability | Higher | Lower |
| Boot time | Faster | Slower |
| Security | Lower | Higher |
| Familiarity | Lower | Higher |
| Isolation | Lower | Higher |
Conclusion
Virtual Machines and Docker both offer different benefits and drawbacks, and the decision of one versus another ultimately comes down to the requirements of the project. If you need complete isolation, or if you are working with legacy applications that won't run in a container, then VMs are a good choice. On the other hand, if you want faster deployment, more portability, and are working with applications that are container-friendly, Docker is a perfect tool for the job.