Dell EMC Networking OS Configuration Guide for the S5048F–ON System 9.14.2.8

Keep the following points in mind when you configure ACL VLAN groups:

• The interfaces where you apply the ACL VLAN group function as restricted interfaces. The ACL VLAN group name identifies the group of VLANs that performs hierarchical filtering.

• You can add only one ACL to an interface at a time.

• When you attach an ACL VLAN group to the same interface, validation performs to determine whether the ACL is applied directly to an interface. If you previously applied an ACL separately to the interface, an error occurs when you attempt to attach an ACL VLAN group to the same interface.

• The maximum number of members in an ACL VLAN group is determined by the type of switch and its hardware capabilities. This scaling limit depends on the number of slices that are allocated for ACL CAM optimization. If one slice is allocated, the maximum number of VLAN members is 256 for all ACL VLAN groups. If two slices are allocated, the maximum number of VLAN members is 512 for all ACL VLAN groups.

• The maximum number of VLAN groups that you can configure also depends on the hardware specifications of the switch. Each VLAN group is mapped to a unique ID in the hardware. The maximum number of ACL VLAN groups supported is 31. Only a maximum of two components (iSCSI counters, Open Flow, ACL optimization, and so on) can be allocated virtual flow processing slices at a time.

• Port ACL optimization is applicable only for ACLs that are applied without the VLAN range.

• If you enable the ACL VLAN group capability, you cannot view the statistical details of ACL rules per VLAN and per interface. You can only view the counters per ACL only using the show ip accounting access list command.

• Within a port, you can apply Layer 2 ACLs on a VLAN or a set of VLANs. In this case, CAM optimization is not applied.

• To enable optimization of CAM space for Layer 2 or Layer 3 ACLs that are applied to ports, the port number is removed as a qualifier for ACL application on ports, and port bits are used. When you apply the same ACL to a set of ports, the port bitmap is set when the ACL flow processor (FP) entry is added. When you remove the ACL from a port, the port bitmap is removed.

• If you do not attach an ACL to any of the ports, the FP entries are deleted. Similarly, when the same ACL is applied on a set of ports, only one set of entries is installed in the FP, thereby saving CAM space. Enable optimization using the optimized option in the ip access-group command. This option is not valid for VLAN and link aggregation group (LAG) interfaces.