Cisco Systems 6000 manual Client-to-CSM-to-Server Traffic Flow

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

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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).

	Catalyst 6000 Family Content Switching Module Installation and Configuration Note
78-11631-02 Rev. A0		7