Small knowledge, big challenge! This article is participating in the creation activity of “Essential Tips for Programmers”.
We’ve heard about physical machines, virtual machines, what is a bare-metal server? Is it a physical machine without a shell?” What exactly does nudity mean? This article introduces you to a rather interesting bare-metal server.
1. Physical Machine era
For a long time, traditional development/operation and maintenance deployment servers need to purchase hardware machines, install the system and some software operating environment, and then configure public IP, hardware firewall, etc., and then build cluster environment to ensure high availability and disaster recovery capability.
This is the era of physical machines, it has the most critical problem, is expensive, all to use physical hardware, really low cost performance. Secondly, management is not convenient, from get blank hardware to build a usable server, the process is complex and difficult, and in the whole process of server operation, monitoring and management is quite troublesome, and it does not support elastic expansion or reduction of precious CPU, I/O resources.
Of course, it is not all bad, it has the advantage of full USE of CPU, I/O performance, that is, no performance loss, resource contention, etc.
Second, virtual private server era
Virtual Private Server, is not very unfamiliar, if you see the English abbreviation VPS (Virtual Private Server) that you will understand again. VPS server is to use virtual technology to divide the physical server into a number of independent space, each independent space is virtual dedicated server, that is, VPS server.
Because the product is virtualized from a physical server, it is not as stable as a physical server, and the computing speed is slower and the performance is not high. Therefore, it is suitable for customers with low configuration requirements.
The main advantage is the price, much cheaper than the physical server, less expensive than the virtual host, more convenient management. Suitable for sites and apps with small budgets.
The disadvantage is that it is inferior to cloud server in capacity expansion, storage and stability, which is why most enterprises choose cloud server.
Cloud server era
Cloud servers differ from VPS in that they are virtual parts of a cluster of servers that resemble independent servers. A server is not a single physical machine, but a physical resource shared by multiple tenants. As shown in the following figure, the location of the VIRTUAL machine is very upper-layer and does not belong to physical resources.
The cloud server features high security and reliability, easy deployment, high scalability (instant expansion and on-demand expansion), and high cost performance. Compared with physical servers, they are more flexible and can be flexibly managed. Prices can be set in real time on demand, avoiding waste of network resources and reducing operating costs.
Because it is a shared resource, so tenants under the same roof, there must be more or less together to do things. For example, despite the commitment of so many resources, the experience of other tenants will be significantly affected due to sudden heavy load, which is absolutely intolerable for applications that require high performance and stability.
Moreover, from the perspective of security, multi-tenant sharing of hardware resources, although there is soft isolation, it is absolutely not safe to use for businesses with high privacy such as banking.
In general, it is only suitable for small and medium-sized websites and applications and businesses with less privacy isolation. Product representatives include Alibaba’s ECS, AWS’s EC2, Tencent’s CVM and so on.
So who can have the performance requirements of physical machine, security isolation, and at the same time have the elastic scaling, flexible management of cloud server? Bare-metal servers.
Next, bare-metal servers, stay tuned!