Alcatel Carrier Internetworking Solutions 6648 User Manual

Page of 614
Unknown Destination
OmniSwitch Troubleshooting Guide
September 2005
page -37
The Coronado ASIC
• The Coronado receives the packet via the FBUS.
• The Coronado then strips the 802.1q header that was added on ingress, if needed.
The Catalina ASIC
• Packet is then put on to the Xybus to be received by the Catalina.
• Catalina Egress will generate the CRC and regulate the packet framing including the interpacket gap.
• The above delivers the first few packets of a flow that has an unknown destination via the flood queue.
Traffic is Being Passed; the Switch is Attempting to Put a 
Correct L2 DA Entry on the NI
The Coronado ASIC
• Ingress Coronado sends IPC messages to all active Coronados on the BBUS inquiring about the desti-
nation address. All the active Coronados look into their L2SA table and if they have a matching entry 
then they sends the Group ID, Mac address, QID, PDI, and request for additional L3/L4 lookups to the 
Ingress Coronado.
• Once this information is put into the L2 DA table of the ingress Coronado, the packets are processed as 
a known DA and are no longer put on the flood queue.