Administrator Guide

Table Of Contents
Consider if the last CAM threshold was set to 90 percent and now you re-configure the CAM threshold to 80. And, if the
current CAM usage is 85 percent, then the system displays the syslog message saying that the CAM usage is above the
configured CAM threshold value.
Table 13. Possible Scenarios of Syslog Warning
Old CAM
Threshold
New CAM
Threshold
Current CAM
Usage
Syslog
90 80 85
DellEMC(conf)#Nov 5
19:55:12 %S6000:0 %ACL_AGENT-4-
ACL_AGENT_CAM_USAGE_OVER_THE_THRESHOLD:
The Ipv4Acl cam region on stack-unit 0
Portpipe 0 Pipeline 0 is more than 80%
Full.
90 95 91
DellEMC(conf)#Nov 5
19:55:12 %S6000:0 %ACL_AGENT-4-
ACL_AGENT_CAM_USAGE_BELOW_THE_THRESHOLD:
The cam-usage of Ipv4Acl cam region on
stack-unit 0 Portpipe 0 Pipeline 0 is
below 95%.
98 100 100 No syslog
95 80 10 No syslog
92 90 89 No syslog
CAM Optimization
When you enable the CAM optimization, 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.
Troubleshoot CAM Profiling
The following section describes CAM profiling troubleshooting.
QoS CAM Region Limitation
To store QoS service policies, the default CAM profile allocates a partition within the IPv4Flow region.
If the QoS CAM space is exceeded, a message similar to the following displays.
%EX2YD:12 %DIFFSERV-2-DSA_QOS_CAM_INSTALL_FAILED: Not enough space in L3
Cam(PolicyQos) for class 2 (Te 1/20/1) entries on portpipe 1 for linecard 1
%EX2YD:12 %DIFFSERV-2-
DSA_QOS_CAM_INSTALL_FAILED: Not enough space in L3 Cam(PolicyQos) for class 5 (Te 1/
22) entries on portpipe 1 for linecard 1
If you exceed the QoS CAM space, follow these steps.
1. Verify that you have configured a CAM profile that allocates 24 K entries to the IPv4 system flow region.
2. Allocate more entries in the IPv4Flow region to QoS.
Dell EMC Networking OS supports the ability to view the actual CAM usage before applying a service-policy. The test cam-
usage service-policy command provides this test framework. For more information, refer to Pre-Calculating Available
QoS CAM Space.
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Content Addressable Memory (CAM)