3Com Switch 7750 Configuration Guide

Choosing ACL Mode for Traffic Flows 639
Layer 2 ACL depth-first order
With the depth-first rule adopted, the rules of a Layer 2 ACL are matched in the
order of the mask length of the source MAC address and destination MAC
address. The longer of the mask is, the higher the match priority is. If two mask
lengths are the same, the priority of the match rule configured earlier is higher. For
example, the priority of the match rule with source MAC address mask
FFFF-FFFF-0000 is higher then the priority of the match rule with source MAC
address mask FFFF-0000-0000.
ACLs Based on Time
Ranges
A time range-based ACL enables you to implement ACL control over packets by
differentiating the time ranges.
A time range can be specified in each rule in an ACL. If the time range specified in
a rule is not configured, the system will give a prompt message and allow such a
rule to be successfully created. However, the rule does not take effect immediately.
It takes effect only when the specified time range is configured and the system
time is within the time range. If you remove the time range of an ACL rule, the
ACL rule becomes invalid the next time the ACL rule timer refreshes.
Types of ACLs Supported
by the Ethernet Switch
The following types of ACLs are supported by the Ethernet switch:
■ Basic ACL
■ Advanced ACL
■ Layer 2 ACL
■ User-defined ACL
Choosing ACL Mode
for Traffic Flows
A switch can only choose one ACL mode for traffic flows, Layer 2 ACL mode or
Layer 3 ACL mode. In Layer 2 ACL mode, only Layer 2 ACL can be activated or
referenced by other applications, and Layer 3 ACL is similar.
Configuration Procedure
n
This configuration is only effective on Type A I/O Modules.
Configuration Example # Configure the ACL mode for traffic flows as link-based.
Table 507 Configure ACL mode for traffic flows
Operation Command Description
Enter system view system-view -
Configure ACL mode for
traffic flows
acl mode { ip-based |
link-based }
Required
By default, a switch chooses
ip-based ACL mode for
traffic flows, that is, ACL
classifies the traffic flows
based on Layer 3 information.
Display the ACL mode for
traffic flows
display acl mode Optional
The display command can be
executed in any view