Load balancing Know?

  Today's society, network and extensive use of universality, creating a rapid growth in traffic and data traffic. The rapid development of the network society, each core part with the improvement in business volume, bound to its processing capacity and computational intensity also made a big ask, if your company uses a single server device, then certainly can not afford a large number of business and At the same time the arrival of traffic. Similar shopping carnival each year - two-eleven in the evening, while the influx of high-volume users, a common server processing power can only reach tens of thousands to hundreds of thousands of requests per second, can not be processed in one second on one million or even more requests. Lack of server processing power to customers on the purchase would cause great distress, while increments in order to better balance the traffic and data traffic, load balancing came into being. It is based on the network structure, provides an effective, transparent, and do not need to bear the high cost way to expand the bandwidth of network devices and servers, enhance network data capacity and improve the flexibility and availability.
  Today, users expect efficient website loading speed, providing a seamless user experience, so if your site must have the reliability and flexibility. Load balancing is what? It is composed of an independent unified entrance to converge traffic, do secondary distribution process, its essence and distributed systems, branch. Now many people are driving, and will use some navigation software, we will find that there will be a limit recommended route navigation software program number, such as three, five. In fact, in essence it also plays a role similar load balancing, because if we can only take the top three unobstructed route, severe congestion of the line would not recommend it to you, then you're driving, traffic pressure is spread over a relatively the free route. In the software system is the same reason, in order to avoid uneven flow allocation, resulting in local node load is too large (such as CPU tight, etc.), this time on the need to set up an independent unified entrance shunt even work to do navigation. However, different load balancing and navigation software system that: Navigation is a flexible strategy, and ultimately requires the user to choose, while the former is different.
  The load balancer is generally based on two factors to decide you want to forward the request to which server.
  1, to ensure that the selected backend server is working properly, the user can give a request to respond;
  2, selected from a pool of healthy server according to a preset load balancing algorithm.
  Since the load balancer should select only the back-end server can respond properly, so you need to have a mechanism to be able to judge it even back-end server is working properly. In order to monitor the health of the back-end server, run status check service periodically tries to use the protocol and port forwarding rules defined to connect to back-end servers. If a server does not pass health checks, it will be removed from the pool of health, to ensure that traffic will not be forwarded to the server until it through a health check up again.