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

Nick Hilliard nick at
Tue May 6 16:11:22 UTC 2014

On 06/05/2014 16:39, Drew Weaver wrote:
> In case anyone wants to check on a 6500, you can run:  show platform
> hardware capacity pfc and then look under L3 Forwarding Resources.

to fix the problem on sup720/rsp720:

> Router(config)#mls cef maximum-routes ip 768

This requires a reload to take effect.  If you don't recarve the TCAM and
you accidentally hit the maximum number of prefixes, the entire chassis
will go into software forwarding mode and will require a reboot to recover.
 IOW, there is no way of avoiding a reload, so best plan as soon as
possible.  More info here:


This problem also affects ASR9000 boxes running typhoon line cards which by
default will only set aside 500k slots for ipv4 prefixes.  The fix for
these boxes is:

> 0/RSP0/CPU0:router# admin hw-module profile scale l3

...followed by appropriate line card reloads.

more information at:



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