Reference Guide

• IP Prefix Lists
• ACL Resequencing
• Route Maps
• Important Points to Remember
IP Access Control Lists (ACLs)
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 system 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.
CAM Usage
The following section describes CAM allocation and CAM optimization.
● User Configurable CAM Allocation
● CAM Optimization
User-Configurable CAM Allocation
User-configurable content-addressable memory (CAM) allows you to specify the amount of memory space that you want to
allocate for ACLs.
To allocate ACL CAM, use the cam-acl command in CONFIGURATION mode. For information about how to allocate CAM for
ACL VLANs, see Allocating ACL VLAN CAM.
The CAM space is allotted in filter processor (FP) blocks. The total space allocated must equal 13 FP blocks. (There are 16 FP
blocks, but System Flow requires three blocks that cannot be reallocated.)
Enter the allocation as a factor of 2 (2, 4, 6, 8, 10). All other profile allocations can use either even or odd numbered ranges.
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.
Test CAM Usage
The test cam-usage command is supported on the Z9500.
This command applies to both IPv4 and IPv6 CAM profiles, but is best used when verifying QoS optimization for IPv6 ACLs.
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Access Control Lists (ACLs)