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You can assign CAM threshold value using cam-threshold command to receive syslog messages when the CAM usage reaches the
congured CAM threshold. The congured CAM threshold is a value specic to FP based on CAM features such as Ingress and Egress L2,
IPV4, IPV6. The system checks the CAM usage of the features with the set threshold to display a syslog message, which contains the
CAM region, slot/port-pipe and pipeline information. By default, syslog warning appears when the CAM usage is 90 percent.
You can also congure the silence period for the syslog message on the CAM usage. A syslog warning appears when the CAM usage
exceeds the congured CAM threshold. The silence period starts after the initial syslog warning. The syslog warning does not appear until
the silence period is active. By default, the silence period is
0 seconds.
Setting CAM Threshold and Silence Period
To congure the CAM threshold and silence period, use the following commands.
• Assign the CAM threshold percentage
CONFIGURATION mode
cam-threshold threshold {default | threshold-percent}
The range of threshold value is from 1 to 100. The default threshold value is 90 percent.
• Assign the silence period for syslog warning.
CONFIGURATION mode
cam-threshold threshold {default | threshold-percent} silence-period {default | silence-
period-value}
The range of silence period is from 0 to 65535. The default is 0 seconds.
NOTE
:
If you delete a FP in a CAM region that is assigned with threshold, a syslog warning appears even during the silence period.
The system triggers syslog during the following events:
• Re-congure the CAM threshold
• Add or delete an ACL rule
Example of Syslog message on CAM usage
Following table shows few possible scenarios during which the syslog message appear on re-conguring the CAM usage threshold value.
Consider if the last CAM threshold was set to 90 percent and now you re-congure 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 congured CAM threshold
value.
Table 10. 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.
240 Content Addressable Memory (CAM)