| US 7,532,620 B2 | ||
| Routing table synchronization method, network apparatus, and routing table synchronization program | ||
| Toshiyuki Sudo, Kawasaki (Japan); Naoki Oguchi, Kawasaki (Japan); and Tetsumei Tsuruoka, Kawasaki (Japan) | ||
| Assigned to Fujitsu Limited, Kawasaki (Japan) | ||
| Filed on Dec. 28, 2004, as Appl. No. 11/23,808. | ||
| Claims priority of application No. 2004-105972 (JP), filed on Mar. 31, 2004. | ||
| Prior Publication US 2005/0220109 A1, Oct. 06, 2005 | ||
| Int. Cl. H04L 12/28 (2006.01); G06F 15/173 (2006.01) | ||
| U.S. Cl. 370—389 [370/218; 370/392; 370/409; 370/466; 370/503; 709/223; 709/239; 709/242; 709/243] | 10 Claims |
| 1. A routing table synchronization method that is used in a network apparatus including a forwarding unit corresponding to
a base point for conducting packet transmission and reception with an external network, and a plurality of control units for
operating a plurality of applications that are arranged to access virtual interfaces of the control units that correspond
to actual interfaces of the forwarding unit so that the network apparatus appears from the outside to be functioning as a
single unit, the routing table synchronization method comprising:
executing a routing process of generating a routing table at a master control unit corresponding to one of the control units;
updating a routing table of the forwarding unit by a routing synchronization process that operates independently from the
routing process if the routing table of the master control unit is updated;
updating one or more routing tables of one or more slave control units corresponding to the control units other than the master
control unit through the forwarding unit;
refraining from transmitting routing information pertaining to at least one of the virtual interfaces to at least one of the
slave control units that implement said at least one of the virtual interfaces if said at least one of the virtual interfaces
is down;
transmitting a signal to at least one of the slave control units to delete routing information pertaining to at least one
of the virtual interfaces from at least one of the routing tables of said at least one of the slave control units if it is
determined that an operating state of said at least one of the virtual interfaces is switched from an up state to a down state;
and
transmitting routing information pertaining to at least one of the virtual interfaces to at least one of the slave control
units that implement said at least one of the virtual interfaces if it is determined that an operation state of said at least
one of the virtual interfaces is switched from a down state to an up state.
|