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
14-23
Cisco MDS 9000 Family CLI Configuration Guide
OL-16184-01, Cisco MDS SAN-OS Release 3.x
Chapter 14 Configuring Generation 2 Switches and Modules
Configuring Generation 2 Module Interface Shared Resources
Use the following guidelines to configure 4-port 10-Gbps switching modules when starting with the
default configuration:
1.
Configure the port mode.
See the
“About Interface Modes” section on page 12-3
.
2.
Configure the BB_credits, performance buffers, and extended BB_credits, as necessary.
See the
“BB_Credit Buffers for Switching Modules” section on page 14-9
,
“BB_Credit Buffers for
Fabric Switches” section on page 14-14
, and the
“Extended BB_Credits” section on page 14-15
.
Configuring Port Speed
The port speed on an interface, combined with the rate mode, determines the amount of shared resources
available to the ports in the port group on a 48-port or 24-port 4-Gbps Fibre Channel switching module.
Especially in the case of dedicated rate mode, the port group resources are reserved even though the
bandwidth is not used. For example, if an interface is configured for autosensing (
auto
) and dedicated
rate mode, then 4 Gbps of bandwidth is reserved even though the maximum operating speed is 2 Gbps.
For the same interface, if autosensing with a maximum speed of 2 Gbps (
auto max 2000
) is configured,
then only 2 Gbps of bandwidth is reserved and the unused 2 Gbps is shared with the other interface in
the port group.
Caution
Changing port speed and rate mode disrupts traffic on the port. Traffic on other ports in the port group
is not affected.
Note
The 4-port 10-Gbps switching module supports 10-Gbps traffic only.
To configure the port speed on an interface on a 4-Gbps switching module, follow these steps:
Use the
show interface
command to verify the port speed configuration for an interface on a 24-port or
48-port 4-Gbps Fibre Channel switching module.
switch#
show interface fc 9/1
Command
Purpose
Step 1
switch#
config t
switch(config)#
Enters configuration mode.
Step 2
switch(config)#
interface fc 1/1
switch(config-if)#
Selects the interface and enters interface
configuration submode.
Step 3
switch(config-if)#
switchport speed 4000
Configures the port speed in megabits per
second. Valid values are
1000
,
2000
,
4000
and
auto
. The
auto
parameter enables autosensing
on the interface.
switch(config-if)#
switchport speed auto
Configures autosensing for the interface with
4 Gbps of bandwidth reserved.
switch(config-if)#
switchport speed auto max
2000
Configures autosensing with a maximum of
2 Gbps of bandwidth reserved.
switch(config-if)#
no switchport speed
Reverts to the default speed for the interface
(
auto
).