Ip Access Control Lists (Acls); Cam Usage - Dell S4820T Configuration Manual

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VRF based IMPLICIT DENY Rules

NOTE: In order for the VRF ACLs to take effect, ACLs configured in the Layer 3 CAM region must

have an implicit-permit option.

You can use the ip access-group command to configure VRF-aware ACLs on interfaces. Using the ip

access-group command, in addition to a range of VLANs, you can also specify a range of VRFs as input

for configuring ACLs on interfaces. The VRF range is from 1 to 63. These ACLs use the existing V4 ACL

CAM region to populate the entries in the hardware and do not require you to carve out a separate CAM

NOTE: You can configure VRF-aware ACLs on interfaces either using a range of VLANs or a range of

VRFs but not both.

IP Access Control Lists (ACLs)

In Dell Networking switch/routers, you can create two different types of IP ACLs: standard or extended.

A standard ACL filters packets based on the source IP packet. An extended ACL filters traffic based on the

following criteria:

IP protocol number

Source IP address

Destination IP address

Source TCP port number

Destination TCP port number

Source UDP port number

Destination UDP port number

For more information about ACL options, refer to the Dell Networking OS Command Reference Guide.

For extended ACL, TCP, and UDP filters, you can match criteria on specific or ranges of TCP or UDP

ports. For extended ACL TCP filters, you can also match criteria on established TCP sessions.

When creating an access list, the sequence of the filters is important. You have a choice of assigning

sequence numbers to the filters as you enter them, or the Dell Networking Operating System (OS) assigns

numbers in the order the filters are created. The sequence numbers are listed in the display output of the

show config and show ip accounting access-list commands.

Ingress and egress Hot Lock ACLs allow you to append or delete new rules into an existing ACL (already

written into CAM) without disrupting traffic flow. Existing entries in the CAM are shuffled to

accommodate the new entries. Hot lock ACLs are enabled by default and support both standard and

extended ACLs and on all platforms.

NOTE: Hot lock ACLs are supported for Ingress ACLs only.

The following section describes CAM allocation and CAM optimization.

User Configurable CAM Allocation

Access Control Lists (ACLs)