| 摘要 |
<p>PROBLEM TO BE SOLVED: To immediately restart communication to a new active system while holding a communication connection equal to a connection just before system switching execution even just after system switching execution. SOLUTION: A redundant LAN system A1 has N pieces of sub LAN systems A21-A2N respectively composed of processors A31-A3N and LAN interface devices A41-A4N to which peculiar MAC addresses are applied, and an inter- processor communication control unit A6 for connecting the processors A31-A3N through a processor bus A5, defining only one of sub LAN systems A21-A2N as an active system and switching the other systems as reserve systems. Just after the sub LAN system of the active system is switched, an ARP packet for updating the ARP cache table of the redundant LAN system from the MAC address of the former active system to the MAC address of the new active system is sent from the sub LAN system of the new active system to all communication equipment.</p> |
