Extreme Networks Px Series - Manual (Page 62)

6-4 Px Series Application Switch Installation and Configuration Guide
Figure 6-1: Client IP persistence mode
The following transactions occur in Figure 6-1:
• The client with IP address 145.12.1.1 transmits its first TCP request to
www.buystuff.com at its VIP address, 64.1.1.7.
• Using its configured load balancing policy, the Px series application switch selects
server 3 as the web server.
• The application switch sends the first request to the selected web server.
• The server sends a request back to the client via the application switch, thus
establishing a session between the server and the client.
• The client sends another request.
• The application switch examines the IP address, sees that the request is from client
125.12.1.1.
• The application switch forwards the request to server 3.
This scenario continues until the session persistence times out.
Client IP persistence mode requires that the IP address of the client remain the same for
the entire session. It does not work if the client IP address changes dynamically within a
session; for example, for large ISPs that conserve IP addresses by using a single proxy
address for many different clients. In this case, use one of the cookie persistence modes.
WS_001
Client
145.12.1.1
Server 1
Server 2
Server 3
64.1.1.7
www.buystuff.com