Cisco AP775A - Nexus Converged Network Switch 5010 Configuration Manual page 470

Policy Types
• Type queuing—A type queuing policy is used to define the scheduling characteristics of the queues
associated with system classes.
Note
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
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◦ Policy—The actions that are performed on the matching traffic are as follows:
A network-qos policy can only be attached to the system qos target.
Note
◦ MTU—The MTU that needs to be enforced for the traffic that is mapped to a system class.
Each system class has a default MTU and the system class MTU is configurable.
◦ Multicast optimization—This configuration specifies if the performance of multicast traffic
mapped to this class will be optimized.
◦ Pause no-drop—No drop specifies lossless service for the system class. Drop specifies that
tail drop is used (arriving packets are dropped when the queue reaches its allocated size)
when a queue for this system class is full.
An additional parameter pfc-cos can be configured. This parameter identifies the class of
service (CoS) values to assert priority flow control (PFC) when traffic for a no-drop system
class is not mapped based purely on CoS experiences congestion.
◦ Queue Limit—This configuration specifies the number of buffers that need to be reserved to
the queues of this system class. This option is not configurable for no-drop system classes.
◦ Set CoS value—This configuration is used to mark 802.1p values for all traffic mapped to
this system class. The marking value for a system class needs to be unique and cannot be
used as a marking value for any other system class.
Some configuration parameters when applied to an EtherChannel are not reflected on
the configuration of the member ports.
◦ Classification—The traffic that matches this class are as follows:
◦ QoS Group—A class-map of type queuing identifies a system-class and is matched by its
associated qos-group.
◦ Policy—The actions that are performed on the matching traffic are as follows:
These policies can be attached to the system qos target or to any interface. The output
Note
queueing policy is used to configure output queues on the switch associated with system
classes. The input queuing policy is used to configure scheduling for queues in the CNA.
The input queuing policy parameters are signalled to the CNA over the DCBX protocol.
◦ Bandwidth—Sets the guaranteed scheduling deficit weighted round robin (DWRR) percentage
for the system class.
◦ Priority—Sets a system class for strict-priority scheduling. Only one system class can be
configured for priority in a given queuing policy.
Information About QoS
OL-16597-01