Reference Guide

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Content Addressable Memory (CAM)
Content addressable memory (CAM) is supported on the S4820T platform.
CAM is a type of memory that stores information in the form of a lookup table. On Dell Networking systems, CAM stores
Layer 2 and Layer 3 forwarding information, access-lists (ACLs), flows, and routing policies. On Dell Networking systems,
there are one or two CAM (Dual-CAM) modules per port-pipe depending on the type of line card.
CAM Profiles
Dell Networking systems partition each CAM module so that it can store the different types of information. The size of
each partition is specified in the CAM profile.
A CAM profile is stored on every card, including each route processor module (RPM). The same profile must be on every
line card and RPM in the chassis.
There is a default CAM profile and several other CAM profiles available so that you can partition the CAM according to
your performance requirements. For example, the default profile has 1K Layer 2 ingress ACL entries. If you need more
memory for Layer 2 ingress ACLs, select the profile l2-ipv4-inacl .
The following table describes the available profiles. The default profile is an all-purpose profile that allocates CAM
space according to the way Dell Networking systems are most commonly used. In general, non-default profiles allocate
more space to particular regions to accommodate specific applications. The size of CAM partitions is measured in
entries. The total CAM space is finite — adding entries to one region necessarily decreases the number available to
other regions.
NOTE: Not all CAM profiles and microcodes are available for all systems. For details regarding available profiles for
each system, refer to the Command Line Interface Reference Guide .
CAM Profile Description
Default An all-purpose profile that allocates CAM space according to the way Dell Networking
systems are most commonly used.
Available Microcodes: default, lag-hash-align, lag-hash-mpls.
eg-default For EG-series line cards only. EG series line cards have two CAM modules per Port-pipe.
Available Microcodes: default, ipv6-extacl.
ipv4-320k Provides 320K entries for the IPv4 FIB and reduces the IPv4 flow partition to 12K.
Available Microcodes: default, lag-hash-mpls.
ipv4-egacl-16k Provides 16K entries for egress ACLs.
Available Microcodes: acl-group.
ipv6-extacl Provides IPv6 functionality.
Available Microcodes: ipv6-extacl.
l2-ipv4-inacl Provides 32K entries for Layer 2 ingress ACLs and 28K entries for Layer 3 IPv4 ingress ACLs.
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