Load balancing technology in LVS cluster

Tag: blank target justify style color

1. throughNATImplement a virtual server (Vs/nat)

650" this.width=650; "title=" clip_image001 "style=" border-left-0px; border-right-width:0px; Background-image:none; border-bottom-width:0px; padding-top:0px; padding-left:0px; margin:0px; padding-right:0px; border-top-width:0px "border=" 0 "alt=" clip_image001 "src=" http://s3.51cto.com/wyfs02/M01/82/BB/ Wkiom1dfnejcsbr-aadnjyzqc04426.jpg "width=" 649 "height=" 605 "/>

vs/nat tcp/ip , which requires only one ip addresses are configured on the scheduler, and server groups can use private ip addresses. The disadvantage is that its scalability is limited, when the number of server nodes rise to 20 , the scheduler itself may become a new bottleneck in the system, because in vs/nat Both request and response messages are required through the load scheduler.

The cluster system based on Vs/nat can be adapted to the performance requirements of many servers. If the load scheduler becomes a new bottleneck in the system, there are three ways to solve this problem: the hybrid approach, vs/tun and . In the dns hybrid cluster system, there are several vs/nat load schedulers, each with its own server cluster, and these load schedulers are Span lang= "en-US" >rr-dns makes up a simple domain name. But vs/tun and vs/dr are a better way to improve system throughput.

2. throughIPThe tunnel implements the virtual server (Vs/tun)

650" this.width=650; "title=" clip_image002 "style=" border-left-0px; border-right-width:0px; Background-image:none; border-bottom-width:0px; padding-top:0px; padding-left:0px; margin:0px; padding-right:0px; border-top-width:0px "border=" 0 "alt=" clip_image002 "src=" http://s3.51cto.com/wyfs02/M02/82/BB/ Wkiom1dfnemy8gthaad1wzg5ppq561.jpg "width=" 691 "height=" 659 "/>

In the vs/tun cluster system, the load scheduler only dispatches requests to a different back-end server, and the back-end server returns the answered data directly to the user. In this way, the load scheduler can handle a large number of requests, soVs/tun can greatly increase the number of servers dispatched by the load scheduler. The Vs/tun Scheduler can dispatch hundreds of servers, which in itself do not become a bottleneck in the system and can be used to build high-performance super servers.

3. virtual servers are implemented through direct routing ( vs/dr "

650" this.width=650; "title=" clip_image003 "style=" border-left-0px; border-right-width:0px; Background-image:none; border-bottom-width:0px; padding-top:0px; padding-left:0px; padding-right:0px; border-top-width:0px "border=" 0 "alt=" clip_image003 "src=" http://s3.51cto.com/wyfs02/M02/82/B9/ Wkiol1dfnvzsuwh8aadz97v6asq297.jpg "width=" 691 "height=" 661 "/>

with Vs/tun method, VS/DR The Scheduler only handles client-to-server connections, and the response data can be returned directly from a separate network route to the customer. This can greatly improve The scalability of the LVS cluster system.

withVs/tuncompared to this method, there is noIPtunnel overhead, but requires that both the load scheduler and the actual server have a NIC attached to the same physical network segment, and the server network device (or device alias) does notARPresponse, or the ability to redirect the message (Redirect) to a localSocketthe port.

Load balancing technology in LVS cluster