Dell PowerEdge FN I/O Module Configuration Guide 9.10(0.0)

This chapter describes access control lists (ACLs), prefix lists, and route-maps.

At their simplest, ACLs, prefix lists, and route-maps permit or deny traffic based on MAC and/or IP addresses. This chapter describes implementing IP ACLs, IP prefix lists and route-maps. For MAC ACLS, refer to Layer 2.

An ACL is essentially a filter containing some criteria to match (examine IP, transmission control protocol [TCP], or user datagram protocol [UDP] packets) and an action to take (permit or deny). ACLs are processed in sequence so that if a packet does not match the criterion in the first filter, the second filter (if configured) is applied. When a packet matches a filter, the switch drops or forwards the packet based on the filter’s specified action. If the packet does not match any of the filters in the ACL, the packet is dropped (implicit deny).

The number of ACLs supported on a system depends on your content addressable memory (CAM) size. For more information, refer to the Content Addressable Memory (CAM) chapter.