3Com Switch 8800 Advanced Software V5 Configuration Guide

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VLAN POLICY CONFIGURATION
When configuring traffic classification and traffic shaping, go to these sections for
information you are interested in:
■ “VLAN Policy Overview” on page 865
■ “Applying VLAN Policy” on page 866
■ “Displaying and Maintaining VLAN Policy” on page 866
■ “VLAN Policy Configuration Examples” on page 866
VLAN Policy Overview QoS policies can be applied in one of the following two modes:
■ Interface-based application: a QoS policy is applied to the incoming packets or
outgoing packets of an interface.
■ VLAN-based application: a QoS policy is applied to all the traffic of a VLAN.
A QoS applied in the interface-based mode is known as an interface policy, and a
QoS policy applied in the VLAN-based mode is known as a VLAN policy. With the
VLAN policy, you can apply QoS policies to a device and manage these policies
conveniently.
On C-type and D-type modules, VLAN policies take effect preferentially. That is, if
packets match the VLAN policy, they do not try to match an interface policy;
otherwise, they search an interface policy. On B-type modules, interface policies
take effect preferentially. With an interface policy applied to an interface, the
packets do not search a VLAN policy no matter whether they match the interface
policy or not.
VLAN policies are invalid on user authentication interfaces. A user authentication
interface joins and exits a VLAN dynamically, and the corresponding VLAN policy is
not applied to the interface.
VLAN policies are invalid on dynamic VLANs. VLAN policies cannot be applied to
dynamic VLANs. For example, with GARP VLAN registration protocol (GVRP)
running, the switch may create a VLAN dynamically, and the corresponding VLAN
policy does not take effect on the dynamic VLANs.
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As flow templates cannot be configured for a VLAN, the fields of the ACL rules in
the QoS policy applied to a VLAN are the fields of the default template.