The following table describes the event IDs, trace collection points, and PRF trace collection levels. The session trace is not output at the point 0x8003.

Table 8-6 Details of trace collection points in a redirector

Event ID	No. in the figure#	Trace acquisition points	Level
0x8000	1	Immediately after acquiring the request processing request	A/B
0x8001	2	Immediately after sending the request header information to a Web container	A/B
0x8002	4	Immediately after receiving a request for the HTTP request body information from the Web container	B
0x8003	6	Immediately after receiving the HTTP response header information from the Web container	B
0x8004	8	Immediately after starting the transmission of the HTTP response body information from the Web container	B
0x8100	11	Immediately after the completion of redirector processing	A/B
0x8101	10	Immediately after receiving the response completion notification from the Web container	A/B
0x8102	3, 5	Immediately before sending the HTTP request body information to the Web container	B
0x8103	7	Immediately after the setup completion of the HTTP response header information in the Web server	B
0x8104	9	Immediately after the completion of transmission of the HTTP response body information to the Web server	B

Legend:

B: Advanced

A/B: Different information is collected for the Standard and Advanced levels

#

Corresponds to the numbers in Figure 8-9.

The following figure shows the trace collection points in a redirector.

Figure 8-9 Trace collection points of a redirector

Because a connection is usually used repeatedly to establish a permanent connection, it is not disconnected during a request. A connection is disconnected only when either an exception occurs during communication, or the upper limit value of the permanent connection is reached.

The output of the trace information is limited at the following points:

Point 3

The trace information is output when the body data is not in the chunk format. When the body data is in the chunk format, the request body request is not sent to the Web server between points 2 and 4, and the request body information is not sent to the Web container.

Points 4 and 5

The trace information is output only in the case of a request for the request body information from the Web container. Furthermore, because the request body information and response body information is sent to the client more than once at the points 4, 5, 8, and 9, the trace information is also output more than once.

Either an invalid session ID might be acquired, or the session ID might not be acquired at the following points:

Points 1 to 5

The session ID can be acquired. However, an invalid session ID (the ID of an HttpSession discarded in a J2EE application, or the ID of an HttpSession discarded due to the expiry of the valid period) might be acquired because the session ID is acquired from the Cookie or URL of the request header.

Even when a valid session ID is acquired, the session might be discarded in the J2EE application.

Points 7 to 11

The session ID can be acquired only when a session is generated.