Quality of Service (QoS): Managing Bandwidth More Effectively

 

Using QoS Types To Configure QoS for Outbound Traffic

 

3. Use qos type-of-service diff-services < incoming-DSCP> dscp < outgoing-

 

DSCP > to change the policy on packets coming from the edge or upstream

 

switch with the specified incoming DSCP.

 

(Figure 6-4on page 6-18illustrates this scenario.)

 

 

N o t e s

“Mixing” ToS DSCP policies and 802.1p priorities is not recommended. Refer

 

to the Note on page 6-9.

 

 

Syntax: qos type-of-service diff-services

Enables ToS diff-services.

qos type-of-service diff-services < current-codepoint> dscp < new-codepoint>

Configures the switch to select an incoming IP packet carrying the <current-codepoint > and then use the <new- codepoint> to assign a new, previously configured DSCP policy to the packet. The policy overwrites the <current- codepoint> with the < new-codepoint > and assigns the 802.1p priority specified by the policy. (Use the qos dscp-mapcommand to define the priority for the DSCPs—page6-32.)

no qos type-of-service

Disables all ToS type operation. Current ToS DSCP policies and priorities remain in the configuration and will become available if you re-enable ToS diff-services.

no qos type-of-service [diff-services < codepoint >]

Deletes the DSCP policy assigned to the

<codepoint > and returns the < codepoint > to the 802.1p priority setting it had before the DSCP policy was assigned. (This will be either a value from 0 - 7 or No-override.)

show qos type-of-service

Displays a listing of codepoints, with any corresponding DSCP policy re-assignments for outbound packets. Also lists the (802.1p) priority for each codepoint that does not have a DSCP policy assigned to it.

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