Thank for your call
regarding running BGP on Cat4500 SupIV. Here is what I have gathered so
On the Cat4500
SupIV, with 512M of SDRAM we have tested with up to 300,000 routes in BGP.
However, our *hardware* only can support 128K routes which includes unicast,
multicast routes, "fastdrop" entries, and routes to directly-connected
hosts. Therefore, 128K of routes is a hard-limit on the SupIV. With
more than 128K routes, hardware forwarding is disabled and default back to
process switching which is not recommended because it can be very
On the Cat6500
SupII, with 512M of DRAM, we should be able to do CEF forwarding on 300,000+ routes. Please
note that the maximum number BGP routes supported is inversely proportional
to the number of neighbors you are peering with.
Here is an
example related to the number of BGP routes supported on the Cat6500,
PFC2/MSFC2 w/ 128MB of memory.
With 512MB of DRAM
on the 6500, we can assume that the number of routes supported is quadruple
based on the table above.
Please let me know
if you need additional information.
Ted Vo, CCIE# 11323
Office Phone: (415) 371-2419