Cabletron Systems SSIM-R8-02 Spécifications télécharger pdf (Page 273)

Enterasys Xpedition User Reference Manual 253

Load Balancing

Adding Servers to the Load Balancing Group

Once a logical server group is created, you specify the servers that can handle client

requests. When the XP receives a client request directed to the virtual server address, it

redirects the request to the actual server address and port. Server selection is done

according to the specified policy.

To add servers to the server group, enter the following command in Configure mode:

Session Persistence

Load balancing clients connect to a virtual IP address, which in reality is redirected to one

of several physical servers in a load balancing group. In many web page display

applications, a client may have its requests redirected to and serviced by different servers

in the group. In certain situations, however, it may be critical that all traffic for the client

be directed to the same physical server for the duration of the session; this is the concept

of session persistence.

When the XP receives a new session request from a client for a specific virtual address, the

XP creates a binding between the client (source) IP address/port socket and the

(destination) IP address/port socket of the load balancing server selected for this client.

Subsequent packets from clients are compared to the list of bindings: if there is a match,

the packet is sent to the same server previously selected for this client; if there is not a

match, a new binding is created. How the XP determines the binding match for session

persistence is configured with the persistence-level option when the load balancing

group is created (see Creating the Server Group on page 252).

There are four configurable levels of session persistence:

• TCP persistence: a binding is determined by the matching the source IP/port address

as well as the virtual destination IP/port address. For example, requests from the client

address of 134.141.176.10:1024 to the virtual destination address 207.135.89.16:80 is

considered one session and would be directed to the same load balancing server (for

example, the server with IP address 10.1.1.1). A request from a different source socket

from the same client address to the same virtual destination address would be

considered another session and may be directed to a different load balancing server

(for example, the server with IP address 10.1.1.2). This is the default level of session

persistence.

Add load balancing servers to a

specific server group.

load-balance add host-to-group <ipaddr/range> group-

name

<group name> port <port number> [weight

<weight>]

Add range of load balancing

servers to a range of server

groups.

load-balance add host-to-vip-range <range> vip-range-

name

<range name> port <port number> [weight

<weight>]

1 2 ... 268 269 270 271 272 273 274 275 276 277 278 ... 393 394

Commentaires sur ces manuels

Pas de commentaire

Cabletron Systems SSIM-R8-02 Spécifications Page 273

Commentaires sur ces manuels

Produits connexes et manuels pour Mise en réseau Cabletron Systems SSIM-R8-02