Users Guide

If a rule is simply appended, existing counters are not affected.
Table 9. L2 and L3 Filtering on Switched Packets
L2 ACL Behavior L3 ACL Behavior Decision on Targeted Traffic
Deny Deny L3 ACL denies.
Deny Permit L3 ACL permits.
Permit Deny L3 ACL denies.
Permit Permit L3 ACL permits.
NOTE: If you configure an interface as a vlan-stack access port, only the L2 ACL filters the packets. The L3 ACL applied
to such a port does not affect traffic. That is, existing rules for other features (such as trace-list, policy-based routing
[PBR], and QoS) are applied to the permitted traffic.
For information about MAC ACLs, refer to Layer 2.
Assign an IP ACL to an Interface
To pass traffic through a configured IP ACL, assign that ACL to a physical interface, a port channel interface, or a VLAN.
The IP ACL is applied to all traffic entering a physical or port channel interface and the traffic is either forwarded or dropped depending on
the criteria and actions specified in the ACL.
The same ACL may be applied to different interfaces and that changes its functionality. For example, you can take ACL “ABCD” and apply
it using the in keyword and it becomes an ingress access list. If you apply the same ACL using the out keyword, it becomes an egress
access list. If you apply the same ACL to the Loopback interface, it becomes a Loopback access list.
This section describes the following:
• Configure Ingress ACLs
• Configure Egress ACLs
For more information about Layer-3 interfaces, refer to Interfaces.
Applying an IP ACL
To apply an IP ACL (standard or extended) to a physical or port channel interface, use the following commands.
1. Enter the interface number.
CONFIGURATION mode
interface interface slot/port
2. Configure an IP address for the interface, placing it in Layer-3 mode.
INTERFACE mode
ip address ip-address
3. Apply an IP ACL to traffic entering or exiting an interface.
INTERFACE mode
ip access-group access-list-name {in} [implicit-permit] [vlan vlan-range | vrf vrf-range]
NOTE:
The number of entries allowed per ACL is hardware-dependent. For detailed specification about entries
allowed per ACL, refer to your line card documentation.
4. Apply rules to the new ACL.
INTERFACE mode
ip access-list [standard | extended] name
To view which IP ACL is applied to an interface, use the show config command in INTERFACE mode, or use the show running-
config command in EXEC mode.
Dell(conf-if)#show conf
!
Access Control Lists (ACLs)
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