S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
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Cisco MDS 9000 Family CLI Configuration Guide
OL-16184-01, Cisco MDS SAN-OS Release 3.x
Chapter 56 Configuring Fabric Congestion Control and QoS
Ingress Port Rate Limiting
Switch 2(config-pmap)#
exit
Switch 2(config)#
Step 3
Repeat
Step 1
through
Step 2
on Switch 1 to address return path congestion at both switches.
Ingress Port Rate Limiting
A port rate limiting feature helps control the bandwidth for individual Fibre Channel ports. Port rate
limiting is also referred to as ingress rate limiting because it controls ingress traffic into a Fibre Channel
port. The feature controls traffic flow by limiting the number of frames that are transmitted out of the
exit point on the MAC. Port rate limiting works on all Fibre Channel ports. The rate limit ranges from 1
to 100% and the default is 100%.
Note
Port rate limiting can only be configured on Cisco MDS 9100 Series switches, Cisco MDS 9216i
switches, and MPS-14/2 modules.
This feature can only be configured if the QoS feature is enabled and if this configuration is performed
on a Cisco MDS 9100 series switch, Cisco MDS 9216i switch, or MPS-14/2 module.
To configure the port rate limiting value, follow these steps.
Default Settings
Table 56-3
lists the default settings for FCC, QoS, and rate limiting features.
.
Command
Purpose
Step 1
switch #
config t
switch(config)#
Enters the configuration mode.
Step 2
switch(config)#
interface fc 1/1
Selects the interface to specify the ingress
port rate limit.
Step 3
switch(config-if)#
switchport
ingress-rate 50
Configures a 50% port rate limit for the
selected interface.
switch(config-if)#
no
switchport
ingress-rate 50
Reverts a previously configured rate to the
factory default of 100%.
Table 56-3
Default FCC, QoS, and Rate Limiting Settings
Parameters
Default
FCC protocol
Disabled.
QoS control traffic
Enabled.
QoS data traffic
Disabled.
Zone-based QoS priority
Low.
Rate limit
100%.
