Web Management Guide-R05

Table Of Contents
Chapter 12
| Security Measures
Access Control Lists
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3. If the result of checking an IP ACL is to permit a packet, but the result of a MAC
ACL on the same packet is to deny it, the packet will be denied (because the
decision to deny a packet has a higher priority for security reasons). A packet
will also be denied if the IP ACL denies it and the MAC ACL accepts it.
Showing
TCAM Utilization
Use the Security > ACL (Configure ACL - Show TCAM) page to show utilization
parameters for TCAM (Ternary Content Addressable Memory), including the
number policy control entries in use, the number of free entries, and the overall
percentage of TCAM in use.
Command Usage
Policy control entries (PCEs) are used by various system functions which rely on
rule-based searches, including Access Control Lists (ACLs), IP Source Guard filter
rules, Quality of Service (QoS) processes, QinQ, MAC-based VLANs, VLAN
translation, or traps.
For example, when binding an ACL to a port, each rule in an ACL will use two PCEs;
and when setting an IP Source Guard filter rule for a port, the system will also use
two PCEs.
Parameters
These parameters are displayed:
Pool Capability Code – Abbreviation for processes shown in the TCAM List.
Unit – Stack unit identifier.
Device – Memory chip used for indicated pools.
Pool – Rule slice (or call group). Each slice has a fixed number of rules that are
used for the specified features.
Tota l – The maximum number of policy control entries allocated to the each
pool.
Used – The number of policy control entries used by the operating system.
Free – The number of policy control entries available for use.
Capability – The processes assigned to each pool.
Web Interface
To show information on TCAM utilization:
1. Click Security, ACL.
2. Select Configure ACL from the Step list.
3. Select Show TCAM from the Action list.