The documentation set for this product strives to use bias-free language. For the purposes of this documentation set, bias-free is defined as language that does not imply discrimination based on age, disability, gender, racial identity, ethnic identity, sexual orientation, socioeconomic status, and intersectionality. Exceptions may be present in the documentation due to language that is hardcoded in the user interfaces of the product software, language used based on RFP documentation, or language that is used by a referenced third-party product. Learn more about how Cisco is using Inclusive Language.
These sections list restrictions for Cisco IOS for the Catalyst 6500 series switches:
The PFC3 removes these restrictions that were present with other policy feature cards:
This section describes general limitations and restrictions:
In releases where caveat CSCef78235 is not resolved:
– With WS-SUP720, hardware revision 3.2 or higher, local SPAN source ports do not copy VACL-redirected traffic.
– With WS-SUP720 hardware revisions lower than 3.2, local SPAN source ports copy VACL-redirected traffic.
– With any Supervisor Engine 720 hardware revision, RSPAN source ports copy VACL-redirected traffic.
Enter the show module version | include WS-SUP720-BASE command to display the hardware revision. For example:
When MAC address reduction is enabled, the root bridge priority becomes a multiple of 4096 plus the VLAN ID. With MAC address reduction enabled, a switch bridge ID (used by the spanning-tree algorithm to determine the identity of the root bridge, the lowest being preferred) can only be specified as a multiple of 4096. Only the following values are possible: 0, 4096, 8192, 12288, 16384, 20480, 24576, 28672, 32768, 36864, 40960, 45056, 49152, 53248, 57344, and 61440.
If another bridge in the same spanning-tree domain does not run the MAC address reduction feature, it could win root bridge ownership because of the finer granularity in the selection of its bridge ID.
– Integrated routing and bridging (IRB)
– Concurrent routing and bridging (CRB)
– Remote source-route bridging (RSRB)
If the last-hop multicast router is a Catalyst 6500 series switch, traffic is forwarded in hardware. In most cases, RPF-MFD is installed for the (S,G) entries. The MSFC does not see the multicast traffic flowing down the SPT and does not send any traffic-triggered (S,G) prunes to stop the flow of traffic down the SPT. This situation does not have any adverse effect on the MSFC because the PFC processes and drops the unwanted (S,G) traffic.
With the ip unreachables command enabled (which is the default), the supervisor engine drops most of the denied packets in hardware and sends only a small number of packets (10 packets per second, maximum) to the MSFC to be dropped, which generates ICMP-unreachable messages.
To eliminate the load imposed on the MSFC CPU by the task of dropping denied packets and generating ICMP-unreachable messages, you can enter the no ip unreachables interface configuration command to disable ICMP unreachable messages, which allows all access-group denied packets to be dropped in hardware.