Four Common server load balancing methods for Enterprises

To improve server performance and workload, enterprises usually use DNS servers, network address translation, and other technologies to achieve multi-server load balancing, many of them use several servers to achieve Load Balancing for server access.

Currently, the so-called "Server Load balancer" used by enterprises is actually a type of control server of the application system. All user requests come to this server first, then, the server assigns the request to a specific processing server based on the actual processing server status. The domain name and IP address exposed to the outside are the server. The server Load balancer control and management software is installed on this server. Generally, this server only distributes Load Balancing tasks, but not the server that actually processes network requests.

1. Enterprises Achieve Web server load balancing

In order to evenly distribute the load to multiple internal servers, a certain load balancing policy must be applied. Server Load balancer equipment is used to achieve dynamic traffic load balancing for each server group, and redundant backups are used for each other. It also requires the new system to have certain scalability. If the data access volume continues to increase, you can add new servers to the Server Load balancer system.

For WEB service applications, several machines provide services at the same time. The status of each machine can be set to regular (working normally) or backup (backup status), or regular state. The server Load balancer device determines the server to which the next user's request will be redirected Based on the server Load balancer algorithm preset by the Administrator and the actual dynamic load of the current network. All of this is completely transparent to users. Users have completed requests for WEB Services and do not need to care about which server is used.

Ii. Use Network Address Translation to achieve multi-server load balancing

In the address translation gateway that supports Server Load balancer, an external IP address can be mapped to multiple internal IP addresses to dynamically use one of the internal addresses for each TCP connection request to achieve the purpose of Server Load balancer. Many hardware vendors integrate this technology into their vswitches as a function of layer-4 switching, generally, the Server Load balancer policy is randomly selected and assigned based on the server connection quantity or response time. However, the hardware-implemented Server Load balancer is not flexible enough to support more optimized Server Load balancer policies and more complex application protocols.

Server Load balancer based on network address translation can effectively solve the CPU and disk I/O loads on servers. However, the performance of Server Load balancer is limited by network I/O, bandwidth is limited under certain hardware conditions. However, you can increase the bandwidth limit by improving algorithms and improving the hardware performance of running the Server Load balancer program. Different service types occupy different server resources. The load measurement strategy we use is to evaluate the same load, which is suitable for most conditions, however, the best way is to monitor the server load for different resources, such as CPU, disk I/O, or network I/O, the central controller selects the most suitable server to distribute customer requests.

Iii. Server Load balancer using DNS

As the number of users accessing CEN servers increases dramatically, it is difficult for a single server to meet users' access needs. How can we ensure normal user access? There are many solutions, such as using Windows 2000 or Windows Server 2003 to provide the network load balancing service, but the settings of this service are very complex. However, implementing network load balancing through DNS is a simple method.

A cen usually consists of many subnets. To reduce the data traffic in the network, it is best for a client to access a Web server in the same subnet. Although the network load balancing function is implemented, it is not guaranteed that the customer accesses the subnetwork's Web server. In fact, this problem is well solved, as long as you enable the "enable network mask sorting" function of the DNS server. In the DNS manager window, right-click the DNS server, select "properties" from the pop-up menu, and switch to the "advanced" tab in the Properties dialog box, select the enable network mask sorting option in the "server options" list box. In this way, the client can access the Web server in the subscriber network every time. After the above settings are completed, the DNS server implements the network load balancing function, shares the customer's access to each Web server, and reduces the network communication traffic across subnets, this greatly reduces the communication burden on enterprise networks.

Iv. Implementing SQL Server database Server load balancing for Enterprises

Ms SQL Server database Server can be said to be the most widely used database products, and more in the large and key application systems to provide services. As enterprise applications become increasingly complex and data volumes increase, SQL Server databases need to constantly process, store, and query data, at this time, enterprises should consider the performance, speed, and security of SQL Server database servers. However, for a long time, SQL SERVER database servers have only "Hot Standby" solutions, but not "SERVER Load balancer" and "cluster" solutions.

With the emergence of database router software ICX, it provides a better cluster solution for database systems based on ms SQL Server. It can truly achieve dynamic load balancing of SQL Server database servers to improve performance and speed; it can truly ensure uninterrupted service provision of SQL Server database servers, when the server fails, the system switches to another server in real time to continue providing services. The switching time is "zero ". The database router is a real-time concurrent Database Transaction Processing synchronous replicaset and Load balancer.

All database customers access the database through ICX. When accessing and querying the SQL Server database, ICX can allocate servers to provide services based on actual conditions, greatly improving service speed and optimizing performance, and implementing load balancing. ICX can connect to multiple databases at the same time. The contents of these databases are completely consistent with those of ICX at any time. That is to say, ICX adopts a new method of concurrent transaction processing to synchronize transaction processing to the connected N databases, so that the system has multiple consistent and up-to-date logical database datasets at any time. When one of the database servers fails, ICX can immediately switch to other servers to continue providing services. Real zero-time server switching greatly improves security and truly realizes uninterrupted server services.