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Content Addressable Memory (CAM)
Content addressable memory (CAM) is supported on Dell Networking OS.
CAM is a type of memory that stores information in the form of a lookup table. On the S5000 systems, CAM stores Layer 2 and Layer 3
forwarding information, access-lists (ACLs), ows, and routing policies.
Topics:
• CAM Allocation
• Re-Allocating CAM for Ingress ACLs and QoS
• Re-Allocating CAM for Egress ACLs
• Testing CAM Usage for QoS Policies
• Displaying CAM-ACL Settings
• Displaying CAM-ACL-Egress Settings
• Conguring CAM Threshold and Silence Period
• CAM Optimization
CAM Allocation
User-congurable CAM allocation is supported on the S5000 switch in separate partitions for ingress and egress ACLs and QoS policies.
You can re-allocate memory space:
• For ingress ACLs and QoS policies by using the cam-acl command in CONFIGURATION mode.
• For egress ACLs by using the cam-acl-egress command in CONFIGURATION mode.
CAM space is allotted in FP blocks. The total allocated space for:
• Ingress CAM regions must equal 13 FP blocks.
• Egress CAM regions must equal four FP blocks.
NOTE
: CAM consists of 16 FP blocks, but System Flow CAM requires three blocks that cannot be re-allocated.
The following table lists the default CAM allocation settings.
Table 12. Default Cam Allocation Settings
CAM Allocation Setting
L2Acl 6
IPV4Acl 4
Ipv6Acl 0
Ipv4Qos 2
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234 Content Addressable Memory (CAM)