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Catalyst 3750 SwitchSoftware Configuration Guide
OL-8550-09
Chapter41 Configuring IPv6 ACLs
Understanding IPv6 ACLs
IPv6 port ACLs
Supported on inbound traffic on Layer 2 interfaces only.
Applied to all IPv6 packets entering the interface.
A switch stack running the IP base image supports only input router IPv6 ACLs. It does not support port
ACLs or output IPv6 router ACLs.
Note If you configure unsupported IPv6 ACLs, an error message appears and the configuration does not take
affect.
The switch does not support VLAN ACLs (VLAN maps) for IPv6 traffic.
Note For more information about ACL support on the switch, see Chapter34, “Configuring Network Security
with ACLs.”
You can apply both IPv4 and IPv6 ACLs to an interface.
As with IPv4 ACLs, IPv6 port ACLs take precedence over router ACLs:
When an input router ACL and input port ACL exist in an SVI, packets received on ports to which
a port ACL is applied are filtered by the port ACL. Routed IP packets received on other ports are
filtered by the router ACL. Other packets are not filtered.
When an output router ACL and input port ACL exist in an SVI, packets received on the ports to
which a port ACL is applied are filtered by the port ACL. Outgoing routed IPv6 packets are filtered
by the router ACL. Other packets are not filtered.
Note If any port ACL (IPv4, IPv6, or MAC) is applied to an interface, that port ACL is used to filter packets,
and any router ACLs attached to the SVI of the port VLAN are ignored.
These sections describe some characteristics of IPv6 ACLs on the switch:
Supported ACL Features, page41-2
IPv6 ACL Limitations, page41-3
IPv6 ACLs and Switch Stacks, page41-3
Supported ACL Features
IPv6 ACLs on the switch have these characteristics:
Fragmented frames (the fragments keyword as in IPv4) are supported.
The same statistics supported in IPv4 are supported for IPv6 ACLs.
If the switch runs out of TCAM space, packets associated with the ACL label are forwarded to the
CPU, and the ACLs are applied in software.
Routed or bridged packets with hop-by-hop options have IPv6 ACLs applied in software.
Logging is supported for router ACLs, but not for port ACLs.