Concept Guide

When priority-tagged frames ingress an untagged port or hybrid port, the frames are classied to the default VLAN of the port and to a
queue according to their dot1p priority if you congure service-class dynamic dotp or trust dot1p. When priority-tagged
frames ingress a tagged port, the frames are dropped because, for a tagged port, the default VLAN is 0.
Dell EMC Networking OS Behavior: Hybrid ports can receive untagged, tagged, and priority tagged frames. The rate metering calculation
might be inaccurate for untagged ports because 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.
Conguring Port-Based Rate Policing
If the interface is a member of a VLAN, you may specify the VLAN for which ingress packets are policed.
• Rate policing ingress trac on an interface.
INTERFACE mode
rate police
Example of the rate police Command
The following example shows conguring rate policing.
DellEMC#configure terminal
DellEMC(conf)#interface gigabitethernet 1/1
DellEMC(conf-if-gi-1/1)#rate police 100 40 peak 150 50
DellEMC(conf-if-gi-1/1)#end
DellEMC#show interfaces tengigabitEthernet 1/2 rate police
Rate police 300 (50) peak 800 (50)
Traffic Monitor 0: normal 300 (50) peak 800 (50)
Out of profile yellow 23386960 red 320605113
Traffic Monitor 1: normal NA peak NA
Out of profile yellow 0 red 0
Traffic Monitor 2: normal NA peak NA
Out of profile yellow 0 red 0
Traffic Monitor 3: normal NA peak NA
Out of profile yellow 0 red 0
Traffic Monitor 4: normal NA peak NA
Out of profile yellow 0 red 0
DellEMC#show interfaces gigabitEthernet 1/2 rate police
Rate police 300 (50) peak 800 (50)
Traffic Monitor 0: normal 300 (50) peak 800 (50)
Out of profile yellow 23386960 red 320605113
Traffic Monitor 1: normal NA peak NA
Out of profile yellow 0 red 0
Traffic Monitor 2: normal NA peak NA
Out of profile yellow 0 red 0
Traffic Monitor 3: normal NA peak NA
Out of profile yellow 0 red 0
Traffic Monitor 4: normal NA peak NA
Out of profile yellow 0 red 0
Conguring Port-Based Rate Shaping
Rate shaping buers, rather than drops, trac exceeding the specied rate until the buer is exhausted. If any stream exceeds the
congured bandwidth on a continuous basis, it can consume all of the buer space that is allocated to the port.
Dell EMC Networking OS Behavior: Rate shaping is eectively rate limiting because of its smaller buer size. Rate shaping on tagged
ports is slightly greater than the congured rate and rate shaping on untagged ports is slightly less than congured rate.
Quality of Service (QoS)
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