Because SUP720-3BXL and because all who have a full BGP feed with it should have seen this in the last days:
*%MLSCEF-SP-4-FIB_EXCEPTION_THRESHOLD: Hardware CEF entry usage is at
95% capacity for IPv4 unicast protocol*
Because 512k routes should be enough for everyone (although the specs advertise 1024k).
Here you will find a workaround:
Ofc, reload is needed 🙁
well, no ipv6 on that machine…
Since the today’s ipv6 full table is only about 17k routes this should give me a year or two to upgrade:
SUP720-3BXL#sh mls cef maximum-routes
FIB TCAM maximum routes :
=======================
Current :-
——-
IPv4 + MPLS – 512k (default)
IPv6 + IP Multicast – 256k (default)
User configured :-
—————
IPv4 – 768k
MPLS – 16k (default)
IPv6 + IP Multicast – 120k (default)
Upon reboot :-
———–
IPv4 – 768k
MPLS – 16k (default)
IPv6 + IP Multicast – 120k (default)
It has begun.
Aug 12 10:19:01: %MLSCEF-DFC4-4-FIB_EXCEPTION_THRESHOLD: Hardware CEF
entry usage is at 95% capacity for IPv4 unicast protocol.
Aug 12 10:49:56: %CFIB-SP-3-CFIB_EXCEPTION: FIB TCAM exception for IPv4
unicast. Packets through some routes will be dropped.
Use “mls cef maximum-routes” to modify the FIB TCAM partition or/and
consider a hardware upgred.
Examine your network and collect the necessary information from this setup.
The only way to recover from this state is by reload the router.