Users Guide

seq 10 permit udp 154.44.0.0 0.0.255.255 host 34.6.0.0
Dell(config-ext-nacl)#
To view all configured IP ACLs and the number of packets processed through the ACL, use the show ip accounting access-
list command in EXEC Privilege mode, as shown in the first example in Configure a Standard IP ACL Filter.
Configure Layer 2 and Layer 3 ACLs
Both Layer 2 and Layer 3 ACLs may be configured on an interface in Layer 2 mode.
If both L2 and L3 ACLs are applied to an interface, the following rules apply:
• When Dell Networking OS routes the packets, only the L3 ACL governs them because they are not filtered against an L2 ACL.
• When Dell Networking OS switches the packets, first the L3 ACL filters them, then the L2 ACL filters them.
• When Dell Networking OS switches the packets, the egress L3 ACL does not filter the packet.
For the following features, if you enable counters on rules that have already been configured and a new rule is either inserted or
prepended, all the existing counters are reset:
• L2 ingress access list
• L3 egress access list
• L2 egress access list
If a rule is simply appended, existing counters are not affected.
Table 7. 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
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Access Control Lists (ACLs)