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Catalyst 3750 SwitchSoftware Configuration Guide
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Chapter41 Configuring IPv6 ACLs
Configuring IPv6 ACLs
Configuring IPv6 ACLs
Before configuring IPv6 ACLs, you must select one of the dual IPv4 and IPv6 SDM templates.
To filter IPv6 traffic, you perform these steps:
Step1 Create an IPv6 ACL, and enter IPv6 access list configuration mode.
Step2 Configure the IPv6 ACL to block (deny) or pass (permit) traffic.
Step3 Apply the IPv6 ACL to an interface. For router ACLs, you must also configure an IPv6 address on the
Layer 3 interface to which the ACL is applied.
These sections describe how to configure and apply IPv6 ACLs:
Default IPv6 ACL Configuration, page41-4
Interaction with Other Features, page 41-4
Creating IPv6 ACLs, page 41-5
Applying an IPv6 ACL to an Interface, page41-7

Default IPv6 ACL Configuration

There are no IPv6 ACLs configured or applied.

Interaction with Other Features

Configuring IPv6 ACLs has these interactions with other features or switch characteristics:
If an IPv6 router ACL is configured to deny a packet, the packet is dropped. A copy of the packet is
sent to the Internet Control Message Protocol (ICMP) queue to generate an ICMP unreachable
message for the frame.
If a bridged frame is to be dropped due to a port ACL, the frame is not bridged.
You can create both IPv4 and IPv6 ACLs on a 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.
You cannot use MAC ACLs to filter IPv6 frames. MAC ACLs can only filter non-IP frames.
If the TCAM is full, for any additional configured ACLs, packets are forwarded to the CPU, and the
ACLs are applied in software.