CLI Reference Guide-R05

Chapter 20 | Class of Service Commands
Priority Commands (Layer 3 and 4)
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Command Usage
◆ Enter a value pair for the internal per-hop behavior and drop precedence,
followed by the keyword “from” and then up to eight DSCP values separated by
spaces.
◆ This map is only used when the QoS mapping mode is set to “DSCP” by the qos
map trust-mode command, and the ingress packet type is IPv4.
◆ Two QoS domains can have different DSCP definitions, so the DSCP-to-PHB/
Drop Precedence mutation map can be used to modify one set of DSCP values
to match the definition of another domain. The mutation map should be
applied at the receiving port (ingress mutation) at the boundary of a QoS
administrative domain.
◆ The specified mapping applies to all interfaces.
Example
This example changes the priority for all packets entering port 1 which contain a
DSCP value of 1 to a per-hop behavior of 3 and a drop precedence of 1. Referring to
Table 114, note that the DSCP value for these packets is now set to 25 (3x2
3
+1) and
passed on to the egress interface.
Console(config)#qos map dscp-mutation 3 1 from 1
Console(config)#
qos map phb-queue This command determines the hardware output queues to use based on the
internal per-hop behavior value. Use the no form to restore the default settings.
Syntax
qos map phb-queue queue-id from phb0 ... phb7
no map phb-queue phb0 ... phb7
phb - Per-hop behavior, or the priority used for this router hop. (Range: 0-7)
queue-id - The ID of the priority queue. (Range: 0-7, where 7 is the highest
priority queue)
Default Setting
.
Command Mode
Global Configuration
Table 115: Mapping Internal Per-hop Behavior to Hardware Queues
Per-hop Behavior 0 1 2 3 4 5 6 7
Hardware Queues 2 0 1 3 4 5 6 7