Getting pretty close to default IPv4 route maximum for 6500/7600 routers.

Łukasz Bromirski lukasz at
Tue Jun 10 17:15:54 UTC 2014

Hi Blake,

On 10 Jun 2014, at 19:04, Blake Hudson <blake at> wrote:

> In this case, does the 512k limit of the 6500/7600 refer to the RIB or the FIB? And does it even matter since the BGP prefix table can automatically be reduced to ~300k routes?

Te 512k limit refers to FIB in the B/C (base) versions of 6500/7600
Supervisors and DFCs (for line cards). BXL/CXL versions have FIB for
1M IPv4 prefixes.

You can find more information here:

And yes, you’re right - no matter how many neighbors you have, the FIB
will only contain best paths, so it will be closer to 500k entries in
total rather than N times number of neighbours.

"There's no sense in being precise when |               Łukasz Bromirski
 you don't know what you're talking     |      jid:lbromirski at
 about."               John von Neumann |

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