Administrator Guide

Ipv6Acl : 2
Dell(conf)#cam-acl-egress-pe l2acl 2 ipv4acl 2 ipv6acl 0
The following example displays the running conguration for the congured CAM ACLs.
Dell(conf)#do show running-config | grep cam-acl
cam-acl l2acl 3 ipv4acl 4 ipv6acl 0 ipv4qos 2 l2qos 1 l2pt 0 ipmacacl 0 vman-qos 0 ecfmacl 0
ipv4pbr 2
cam-acl-pe l2acl 3 ipv4acl 2 ipv6acl 2 ipv4qos 2 l2qos 1 ipmacacl 2
cam-acl-egress-pe l2acl 2 ipv4acl 2 ipv6acl 0
Implementing ACLs
You can assign one IP ACL per physical or VLAN interface. If you do not assign an IP ACL to an interface, it is not used by the software in
any other capacity.
The number of entries allowed per ACL is hardware-dependent.
If you enable counters on IP ACL rules that are already congured, those counters are reset when a new rule is inserted or prepended. If a
rule is appended, the existing counters are not aected. This is applicable to the following features:
• L2 Ingress Access list
• L2 Egress Access list
• L3 Egress Access list
ACLs and VLANs
There are some dierences when assigning ACLs to a VLAN rather than a physical port.
For example, when using a single port-pipe, if you apply an ACL to a VLAN, one copy of the ACL entries is installed in the ACL CAM on the
port-pipe. The entry looks for the incoming VLAN in the packet. Whereas if you apply an ACL on individual ports of a VLAN, separate
copies of the ACL entries are installed for each port belonging to a port-pipe.
When you use the log keyword, the CP has to log the details about the packets that match. Depending on how many packets match the
log entry and at what rate, the CP might become busy as it has to log these packets’ details. However, the Route Processor (RP) is
unaected. This option is typically useful when debugging some problem related to control trac. We have used this option numerous
times in the eld and have not encountered problems so far.
ACL Optimization
If an access list contains duplicate entries, the system deletes one entry to conserve CAM space.
Standard and extended ACLs take up the same amount of CAM space. A single ACL rule uses two CAM entries whether it is identied as a
standard or extended ACL.
Determine the Order in which ACLs are Used to Classify Trac
When you link class-maps to queues using the service-queue command, the system matches the class-maps according to queue
priority (queue numbers closer to 0 have lower priorities).
As shown in the following example, class-map cmap2 is matched against ingress packets before cmap1.
ACLs acl1 and acl2 have overlapping rules because the address range 20.1.1.0/24 is within 20.0.0.0/8. Therefore (without the keyword
order), packets within the range 20.1.1.0/24 match positive against cmap1 and are buered in queue 7, though you intended for these
packets to match positive against cmap2 and be buered in queue 4.
Access Control Lists (ACLs)
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