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

joel jaeggli joelja at
Tue Jun 10 17:33:56 UTC 2014

On 6/10/14, 10:15 AM, Łukasz Bromirski wrote:
> 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.

Until you add multi-as multipath and addpath and a couple VRFs and all
of sudden FIB budget blows up.

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