Quality of Service (QoS): Managing Bandwidth More Effectively

Using QoS Classifiers To Configure Quality of Service for Outbound Traffic

Codepoint Default

Priority

001100 1

001101 No-override

001110 2

If you change all three settings to a priority of 3, and then execute write memory, the switch will reflect these changes in the show config listing:

Configure these three codepoints with non-default priorities.

Show config lists the non default codepoint settings.

Figure 15-31. Example of Show Config Listing with Non-Default Priority Settings in the DSCP Table

Effect of No-override”.In the QoS Type-of-Service differentiated services mode, a No-overrideassignment for the codepoint of an outbound packet means that QoS is effectively disabled for such packets. That is, QoS does not affect the packet queuing priority or VLAN tagging. In this case, the packets are handled as follows (as long as no other QoS feature creates priority assignments for them):

802.1Q Status

Outbound 802.1p

 

Priority

 

 

Received and Forwarded on a tagged VLAN

Unchanged

Received on an Untagged VLAN; Forwarded on a

0 (zero)—”normal”

tagged VLAN

 

Forwarded on an Untagged VLAN

None

 

 

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