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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.
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IPv6 port ACLs are supported on inbound Layer 2 interfaces. IPv6 port ACLs are applied to all IPv6
packets entering the interface.
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VLAN ACLs or VLAN maps access-control all packets in a VLAN. You can use VLAN maps to filter
traffic between devices in the same VLAN. ACL VLAN maps are applied on L2 VLANs. VLAN maps
are configured to provide access control based on Layer 3 addresses for IPv6. Unsupported protocols
are access-controlled through MAC addresses using Ethernet ACEs. After a VLAN map is applied to a
VLAN, all packets entering the VLAN are checked against the VLAN map.
The switch does not support VLAN ACLs (VLAN maps) for IPv6 traffic.
You can apply both IPv4 and IPv6 ACLs to an interface. As with IPv4 ACLs, IPv6 port ACLs take precedence
over router ACLs.
Switch Stacks and IPv6 ACLs
The active switch supports IPv6 ACLs in hardware and distributes the IPv6 ACLs to the stack members.
If a standby switch takes over as the active switch, it distributes the ACL configuration to all stack members.
The member switches sync up the configuration distributed by the new active switch and flush out entries
that are not required.
When an ACL is modified, attached to, or detached from an interface, the active switch distributes the change
to all stack members.
Interactions with Other Features and Switches
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If an IPv6 router ACL is configured to deny a packet, the packet is not routed. A copy of the packet is
sent to the Internet Control Message Protocol (ICMP) queue to generate an ICMP unreachable message
for the frame.
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If a bridged frame is to be dropped due to a port ACL, the frame is not bridged.
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You can create both IPv4 and IPv6 ACLs on a switch or switch stack, and you can apply both IPv4 and
IPv6 ACLs to the same interface. Each ACL must have a unique name; an error message appears if you
try to use a name that is already configured.
You use different commands to create IPv4 and IPv6 ACLs and to attach IPv4 or IPv6 ACLs to the same
Layer 2 or Layer 3 interface. If you use the wrong command to attach an ACL (for example, an IPv4
command to attach an IPv6 ACL), you receive an error message.
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You cannot use MAC ACLs to filter IPv6 frames. MAC ACLs can only filter non-IP frames.
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If the hardware memory is full, packets are dropped on the interface and an unload error message is
logged.
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Configuring IPv6 ACLs
Switch Stacks and IPv6 ACLs