Differences between clusters, distributed computing, and Server Load balancer

A cluster is a general term. It can be divided into several types, such as high-performance scientific clusters, Server Load balancer clusters, and high-availability clusters.
Scientific Cluster
Generally, this cluster involves developing parallel programming applications for clusters.ProgramTo solve complex scientific problems. Instead of dedicated super parallel computers, it uses commercial systems (such as a group of single-processor or dual-processor PCs linked through high-speed connections ), in addition, communication is performed on the public message transmission layer to run parallel applications. We often hear about the advent of a cheap Linux supercomputer. In most cases, it refers to a cluster system with the same processing capability as a real supercomputer, the price is quite lower than that of a dedicated supercomputer with millions of dollars.
Server Load balancer Cluster
Server Load balancer clusters provide a more practical system for enterprises. Such a system allows the load to be evenly distributed among multiple computers as much as possible. A server Load balancer can be used by applications that need to be balanced to handle loads or network traffic loads. In the system, each node can handle part of the load and dynamically allocate the load between nodes to achieve a balance. This is also true for network traffic.
High Availability Cluster
A high-availability cluster is designed to make the overall services of the cluster as available as possible. If the master node in the HA cluster fails, it will be replaced by the secondary Node during this period of time. The secondary node is usually an image of the master node, so when it replaces the master node, it can take over its identity completely without affecting the user.
These three basic types of a cluster often overlap and mix. For example, in a highly available cluster system, Server Load balancer can be implemented between nodes while maintaining high availability.

 

Main Application of Load Balancing Technology

1. The earliest DNS Server Load balancer technology was implemented through DNS. In DNS, the same name is configured for multiple addresses. Therefore, the client that queries this name will get an address, in this way, different customers can access different servers to achieve load balancing. DNS Server Load balancer is a simple and effective method, but it cannot distinguish between servers or reflect the current running status of servers.
2. The Server Load balancer of the proxy server can forward requests to internal servers. Using this acceleration mode can obviously increase the access speed of static webpages. However, this technology can also be considered to use a proxy server to evenly forward requests to multiple servers, so as to achieve load balancing.
3. address translation gateway Server Load balancer supports the address translation gateway of Server Load balancer. You can map an external IP address to multiple internal IP addresses to dynamically use one of the internal addresses for each TCP connection request, achieve the purpose of load balancing.
4. In addition to the three Server Load balancer methods, some protocols support Server Load balancer-related functions, such as HTTP redirection, HTTP runs on the top layer of the TCP connection.
5. Nat Server Load balancer NAT (Network Address Translation) simply converts an IP address to another IP address, it is generally used to convert unregistered internal addresses to valid and registered Internet IP addresses. It is applicable to situations where Internet IP addresses are insufficient and you do not want to know the internal network structure outside the network.
6. Reverse Proxy Server Load balancer common proxy is a connection request sent by a proxy internal network user to access a server on the Internet. The client must specify the proxy server, and send the connection request that was originally sent directly to the server on the Internet to the proxy server for processing. The reverse proxy method is to use a proxy server to accept connection requests from the Internet, and then forward the requests to the server on the internal network, return the result obtained from the server to the Client Requesting connection from the Internet. The proxy server is displayed as a server. The Reverse Proxy Server Load balancer technology dynamically forwards connection requests from the Internet to multiple servers in the internal network for processing in the form of reverse proxy, so as to achieve the purpose of load balancing.
7. Hybrid server Load balancer is deployed in some large networks. Due to the differences in hardware devices, sizes, and services in multiple Server Clusters, we can consider using the most appropriate load balancing method for each server group, then, the Server Load balancer or cluster is used to provide services to the outside world in one whole (that is, the Server Load balancer group is regarded as a new Server Load balancer group ), to achieve the best performance. This method is called hybrid load balancing. This method is sometimes used when the performance of a single balanced device cannot meet a large number of connection requests.