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S e n d f e e d b a c k t o n x 5 0 0 0 - d o c f e e d b a c k @ c i s c o . c o m
1-12
Cisco Nexus 5000 Series Switch CLI Software Configuration Guide
OL-16597-01
Chapter 1 Configuring QoS
Configuring System Classes
switch(config-cmap)#
exit
switch(config)#
policy-map ethNoDrop
switch(config-pmap)#
class ethCoS4
switch(config-pmap-c)#
pause no-drop
switch(config)#
system qos
switch(config-system)#
service-policy ethNoDrop
System Class Example
In the following example, a new Ethernet no-drop system class is created, and the CoS values of the
default system classes are changed from their default values:
switch(config)#
class-map
trading-data-no-drop
switch(config-cmap)#
match cos
5
switch(config)#
class-map
class-fcoe
switch(config-cmap)#
match cos 2
switch(config)#
policy-map
system-policy
switch(config-pmap)#
class
trading-data-no-drop
switch(config-pmap-c)#
pause no-drop
switch(config-pmap-c)#
mtu
2000
switch(config)#
system qos
switch(config-system)#
service-policy
system-policy
In this example, the first
class-map
command defines a new Ethernet system class. Packets from all over
the system with 802.1p CoS value of 5 will be classified into this new system class.
The second
class-map
command changes the match value of the default no-drop system class.
The
policy-map
command defines a QoS policy for each traffic class. The new Ethernet class is
configured as a no-drop class, with an MTU of 2000 bytes. The
pause no-drop
command causes PFC
to apply pause functionality for packets with IEEE 802.1p priority value 5.
The
service-policy
command sets the specified policy as the system class.
Enabling Jumbo MTU
To enable jumbo MTU for the whole switch, set the MTU to its maximum size (9216 bytes) in the policy
map for the default Ethernet system class (class-default).
In the following example, the default Ethernet system class is configured to support the jumbo MTU:
switch(config)#
policy-map jumbo
switch(config-pmap)#
class class-default
switch(config-pmap-c)#
mtu 9216
switch(config)#
system qos
switch(config-system)#
service-policy jumbo
Note
The
system jumbomtu
command defines the maximum MTU size for the switch. However, jumbo MTU
is only supported for system classes that have
mtu
configured.
Verifying Jumbo MTU
To verify that jumbo MTU is enabled, enter the
show interface ethernet
slot/port
command for an
Ethernet interface that carries traffic with jumbo MTU.