Reference Guide

722 | Quality of Service (QoS)
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On the S5000 you can configure service-class dynamic dot1p from CONFIGURATION mode, which applies
the configuration to all interfaces. A CONFIGURATION mode
service-class dynamic dot1p entry supersedes
any INTERFACE entries. See Mapping dot1p values to service queues on page 730.
Figure 40-3. service-class dynamic dot1p Command Example
Priority-tagged Frames on the Default VLAN
Priority-tagged Frames on the Default VLAN is available on the S5000 switch.
Priority-tagged frames are 802.1Q tagged frames with VLAN ID 0. For VLAN classification these packets
are treated as untagged. However, the dot1p value is still honored when
service-class dynamic dot1p or trust
dot1p
is configured.
When priority-tagged frames ingress an untagged port or hybrid port the frames are classified to the default
VLAN of the port, and to a queue according to their dot1p priority dot1p priority if
service-class dynamic
dotp
or trust dot1p are configured. When priority-tagged frames ingress a tagged port, the frames are
dropped because for a tagged port the default VLAN is 0.
Configuring Port-based Rate Policing
Rate policing ingress traffic on an interface using the command rate police from INTERACE mode, as
shown in Figure 40-4. If the interface is a member of a VLAN, you may specify the VLAN for which
ingress packets are policed.
Figure 40-4. Rate Policing Ingress Traffic
Note: You cannot configure service-policy input and service-class dynamic dot1p on the same interface.
Dell Networking OS Behavior: Hybrid ports can receive untagged, tagged, and priority tagged frames. The rate
metering calculation might be inaccurate for untagged ports, since an internal assumption is made that all frames
are treated as tagged. Internally the ASIC adds a 4-bytes tag to received untagged frames. Though these 4-bytes
are not part of the untagged frame received on the wire, they are included in the rate metering calculation resulting
in metering inaccuracy.
Dell#config t
Dell(conf)#interface tengigabitethernet 1/0
Dell(conf-if)#service-class dynamic dot1p
Dell(conf-if)#end
Dell#
Dell#config t
Dell(conf)#interface tengigabitethernet 1/0
Dell(conf-if)#rate police 100 40 peak 150 50
Dell(conf-if)#end
Dell#