
Overview
Client-to-CSM-to-Server  Traffic Flow
This section describes how the traffic flows between the client and server in a CSM environment. (See Figure 3.)
Figure 3 Client-to-Content  Switching Module-to-Server  Traffic Flow
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4VIP
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DNS server
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 X
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www.example.com web server farm
47528
Note The numbers in Figure 3 refer to the steps in the following procedure.
When you enter a request for information by entering a URL, the traffic flow is as follows:
Step 1 You enter a URL. (For example, in Figure 3 you enter www.fox.com.)
Step 2 The client contacts a DNS server to locate the IP address associated with the URL you entered. Step 3 The DNS server sends the IP address of the virtual IP (VIP) to the client.
Step 4 The client uses that IP address (CSM VIP) to send the HTTP request to the CSM.
Step 5 The CSM receives the request with the URL, makes a load balancing decision, and selects a server. For example, in Figure 3, the CSM selects a server (X server) from the www.fox.com server pool, replacing its own VIP address with the address of the X server and forwards the traffic to the X server.
Step 6 The CSM performs the Network Address Translation (NAT).
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