| 摘要 |
<p>PROBLEM TO BE SOLVED: To collect a trace while making use of high speed property of communication. SOLUTION: An MAC frame received by an Ether port 1 is hard-copied in an MAC frame hard copy part 2 and is distributed/transmitted to the buffer part 3 of an active system and the buffer part 4 of a non-active system. When a CPU part 6 is not congested, the MAC frame collected from the buffer 4 is written into a dual memory as trace information. When the CPU part 6 is congested, a congestion control signal is transmitted from the CPU part 6 to the buffer part 4 and the buffer part 4 temporarily accumulates the MAC frame which is not processed. When the system is switched, CPU 6 outputs the MAC frame left in the buffer part 4 to the dual memory 9.</p> |
