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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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Chapter 38 Configuring IPv6 ACLs
Understanding IPv6 ACLs
Understanding IPv6 ACLs
A switch supports two types of IPv6 ACLs:
• IPv6 router ACLs are supported on outbound or inbound traffic on Layer 3 interfaces, which can be
routed ports, switch virtual interfaces (SVIs), or Layer 3 EtherChannels. IPv6 router ACLs apply
only to IPv6 packets that are routed.
• IPv6 port ACLs are supported on inbound traffic on Layer 2 interfaces only. IPv6 port ACLs are
applied to all IPv6 packets entering the interface.
A switch running the IP base feature set 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 Chapter 37, “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, page 38-2
• IPv6 ACL Limitations, page 38-3
• IPv6 ACLs and Switch Stacks, page 38-3

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 hardware space, packets associated with the ACL are forwarded to the CPU,
and the ACLs are applied in software.