Руководство По Проектированию для Cisco Cisco Nexus 5010 Switch
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For instance, if you want to make the class VideoAndSignaling a no-drop class, you can configure it as follows:
class-map type network-qos CriticalData
match qos-group 3
class-map type network-qos Scavenger
match qos-group 2
class-map type network-qos VideoAndSignaling
match qos-group 4
policy-map type network-qos globalnetworkpolicy
class type network-qos VideoAndSignaling
pause no-drop
The number of no-drop classes that can be configured depends on whether you are using the Cisco Nexus 5010 or
5020 or the Cisco Nexus 5500 platform.
On the Cisco Nexus 5500 platform, the hardware supports up to four no-drop traffic classes; the exact number of
configurable ones varies by release.
On the Cisco Nexus 5010 and 5020, the following rules apply:
●
If the total number of QoS groups is less than or equal to four (including QoS group 0 and QoS group 1 if
defined), then the user can configure three total no-drop classes (of which one is used by QoS group 1 for
FCoE if QoS group 1 is defined).
●
If the total number of QoS groups is more than four, a total of two no-drop classes can be defined, of which
one is used by QoS group 1 for FCoE if QoS group 1 is defined).
More About type network-qos Policies
You can use type network-qos polices for the following configurations:
●
Setting up the MTU for a traffic class
●
Setting up drop or no-drop behavior
●
Setting the queue limit for a traffic class
The network QoS policy can be applied only under system qos; it cannot be configured under an individual
interface.
Egress Scheduling and Priority Queuing
To determine the bandwidth allocation for the traffic from the Cisco Nexus 5000 Series to the wire, you need to use
policy-map type queuing, which allows you to define the bandwidth percentage used by each traffic class.
This policy map is applied in the egress direction.
The ingress policy map is applied for two main purposes:
●
For DCBX, to set up the proper bandwidth allocation on the CNA
●
To program the bandwidth allocation on the fabric extender for traffic from the host ports to the network
ports (often referred to as H2N traffic)
The following is a sample configuration for the egress queuing policy:
class-map type queuing CriticalData
match qos-group 3