Which three iRule events are likely to be seen in iRules designed to select a...

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In the BIG-IP system, pool selection must occur on theclient-sideof the connection, before the system attempts to connect to a pool3member. The events listed4are the primary entry points for making these decisions:

CLIENT_ACCEPTED (E):This is a Layer 4 event triggered when the BIG-IP accepts a TCP connection. It is the earliest point where a pool can be assigned based on the client's source IP address or the destination port.

CLIENT_DATA (A):This event is triggered when the system receives a "chunk" of data on the client-side. It is often used for non-HTTP protocols (like custom TCP protocols) to inspect the payload and select a pool based on its contents.

HTTP_REQUEST (C):This is a Layer 7 event. It occurs once the BIG-IP has fully parsed the HTTP headers. This is the most common event for pool selection, allowing the administrator to route traffic based on the URI, Host header, or cookies.

Events like SERVER_SELECTED or SERVER_CONNECTED occurafterthe load balancing decision has already been made, and HTTP_RESPONSE or SERVER_DATA occur after the server has already started communicating back, making them too late for initial pool selection.