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Save the new CAM settings to the startup-config (use write-mem or copy run start) then reload the system for the new
settings to take effect.
CAM Optimization
When you enable this command, if a policy map containing classification rules (ACL and/or dscp/ ip-precedence rules) is applied
to more than one physical interface on the same port-pipe, only a single copy of the policy is written (only one FP entry is used).
When you disable this command, the system behaves as described in this chapter.
Test CAM Usage
This command applies to both IPv4 and IPv6 CAM profiles, but is best used when verifying QoS optimization for IPv6 ACLs.
To determine whether sufficient ACL CAM space is available to enable a service-policy, use this command. To verify the actual
CAM space required, create a class map with all the required ACL rules, then execute the test cam-usage command in
Privilege mode. The following example shows the output when executing this command. The status column indicates whether
you can enable the policy.
Example of the test cam-usage Command
DellEMC#test cam-usage service-policy input asd stack-unit 1 port-set 0
Stack-unit|Portpipe|CAM Partition|Available CAM|Estimated CAM per Port|Status
--------------------------------------------------------------------------
1| 1| IPv4Flow| 232| 0|Allowed
DellEMC#
Allocating ACL VLAN CAM
CAM optimization for ACL VLAN groups is not enabled by default. You must allocate blocks of ACL VLAN CAM to enable ACL
CAM optimization by using the cam-acl-vlan command.
By default, 0 blocks of CAM are allocated for VLAN services in the VLAN Content Aware Processor (VCAP), an application
that modifies VLAN settings before forwarding packets on member interfaces. The cam-acl-vlan {vlanaclopt |
vlaniscsi | vlanopenflow} command allows you to allocate filter processor (FP) blocks of memory for ACL VLAN
services: iSCSI counters, Open Flow, and ACL VLAN optimizationOpen Flow and ACL VLAN optimization.
You can configure CAM allocation for only two of these VLAN services at a time. You can allocate from 0 to 2 FP blocks for
each VLAN service.
To allocate the number of FP blocks for ACL VLAN optimization, enter the cam-acl-vlan vlanaclopt <0-2> command.
After you configure ACL VLAN CAM, reboot the switch to enable CAM allocation for ACL VLAN optimization.
To display the number of FP blocks currently allocated to different ACL VLAN services, enter the show cam-acl-vlan
command.
To display the amount of CAM space currently used and available for Layer 2 and Layer 3 ACLs on the switch, enter the show
cam-usage command.
Implementing ACLs on Dell EMC Networking OS
You can assign one IP ACL per interface. If you do not assign an IP ACL to an interface, it is not used by the software.
The number of entries allowed per ACL is hardware-dependent.
If counters are enabled on ACL rules that are already configured, those counters are reset when a new rule which is inserted
or prepended or appended requires a hardware shift in the flow table. Resetting the counters to 0 is transient as the proginal
counter values are retained after a few seconds. If there is no need to shift the flow in the hardware, the counters are not
affected. This is applicable to the following features:
● L2 Ingress Access list
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Access Control Lists (ACLs)