cluster, distributed, load balancing differences and linkages

1, the Linux cluster is divided into three main categories (high-availability cluster, load-balanced cluster, scientific computing cluster) (only load Balancing cluster is described below)
Load Balancer cluster (load Balance Cluster)
Load balancing system: All nodes in the cluster are active and they share the workload of the system. Generic Web server clusters, DB clusters, and application server clusters are of this type.

A load Balancer cluster is typically used for Web servers, database servers, for corresponding network requests. This cluster can, upon request, check for servers that accept fewer requests, are not busy, and transfer requests to those servers. From the point of checking other server states, load balancing and fault tolerant clusters are very close, and the difference is more in number.


2, Load Balancing system: Load balancing and DNS load balancing (more commonly used), IP load Balancing, reverse proxy load balancing, and so on, in the cluster there are servers A, B, C, they are non-impact, mutual irrelevant, any one machine downtime, will not affect the operation of other machines, when the user to a request, The algorithm of the load balancer decides which machine to handle, if your algorithm uses the round algorithm, has the user A, B, C, then respectively by Server A, B, c to handle;


3, distributed refers to the distribution of different businesses in different places.
Clustering, however, refers to centralizing several servers together to achieve the same business.
Each node in the distribution can be a cluster.
Clusters are not necessarily distributed.
Example: For example, Sina, the number of people who visit, he can do a cluster, the front of a response server, the next few servers to complete the same business, if there is business access, the response server to see which server load is not very heavy, will be to which to complete.
and distributed, from the narrow meaning of understanding, but also similar to the cluster, but its organization is relatively loose, unlike clustering, there is an organizational, a server collapsed, the other servers can be top up.
distributed to each node, the completion of a different business, a node collapsed, which business is inaccessible.

cluster, distributed, load balancing differences and linkages