hardware buffer-threshold

To limit the amount of input hardware buffer usage for each Fabric Extender, use the hardware buffer-threshold command. To revert to the default and allow a Fabric Extender to use all available hardware buffer space, use the no form of this command.

hardware fex_card_typ buffer-threshold buffer-limit

no hardware fex_card_typ buffer-threshold

Syntax Description

fex_card_type

Fabric Extender card type. The following Fabric Extender card types are supported:

•N2148T—Fabric Extender 48x1G 4x10G SFP+ Module

•N2224TP—Fabric Extender 24x1G 2x10G SFP+ Module

•N2232P—Fabric Extender 32x10G SFP+ 8x10G SFP+ Module

•N2248T—Fabric Extender 48x1G 4x10G SFP+ Module

See the "Usage Guidelines" section for a description of these Fabric Extenders.

buffer-limit

Buffer threshold limit in bytes. The range is from 81920 to 316160.


Command Default

None

Command Modes

Fabric extender configuration mode

Command History

Release
Modification

4.2(1)N2(1)

This command was introduced.


Usage Guidelines


Note This command is available only on a Cisco Nexus 2148T Fabric Extender.


The buffer-threshold keyword sets the consumption level of input buffers before an indication is sent to the egress queue to start observing the tail drop threshold. If the buffer usage is lower than the configured buffer threshold, the tail drop threshold is ignored.

Supported Cisco Nexus 2000 Series Fabric Extender

The following Cisco Nexus 2000 Series Fabric Extenders are supported on a Cisco Nexus 5000 Series switch that runs a Cisco NX-OS release 4.2(1)N2(1):

•Cisco Nexus 2148T Fabric Extender—It has four 10-Gigabit Ethernet fabric interfaces for its uplink connection to the parent Cisco Nexus 5000 Series switch and 48 1000BASE-T (1-Gigabit) Ethernet host interfaces for its downlink connection to servers or hosts.

•Cisco Nexus N2224TP Fabric Extender—It has two 10-Gigabit Ethernet fabric interfaces with  small form-factor pluggable (SFP+) interface adapters for its uplink connection to the parent  Cisco Nexus 5000 Series switch and 24 1000BASE-T (1-Gigabit) Ethernet host interfaces for its  downlink connection to servers or hosts. It does not support Fibre Channel over Ethernet (FCoE).

•Cisco Nexus 2232P Fabric Extender—It has eight 10-Gigabit Ethernet fabric interfaces with small form-factor pluggable (SFP+) interface adapters for its uplink connection to the parent Cisco Nexus 5000 Series switch and 32 10-Gigabit Ethernet fabric interfaces with SFP+  interface adapters for its downlink connection to servers or hosts.

•Cisco Nexus 2248T Fabric Extender—It has four 10-Gigabit Ethernet fabric interfaces with  SFP+ interface adapters for its uplink connection to the parent  Cisco Nexus 5000 Series switch and 48 1000BASE-T (1-Gigabit) Ethernet host interfaces for its  downlink connection to servers or hosts.

Examples

This example shows how to configure the hardware buffer threshold limit on a Cisco Nexus 2148T Fabric Extender:

switch(config)# fex 110 
switch(config-fex)# hardware N2148T buffer-threshold 163840 
switch(config-fex)# 

This example shows how to remove the hardware buffer threshold configured on a Cisco Nexus 2148T Fabric Extender:

switch(config)# fex 110 
switch(config-fex)# no hardware N2148T buffer-threshold 
switch(config-fex)# 

Related Commands

Command
Description

fex

Creates a Fabric Extender and enters fabric extender configuration mode.

show fex

Displays all configured Fabric Extender chassis connected to the switch.

show queuing interface

Displays information about interface queuing parameters, including buffer threshold and queue limits.

show running-config fex

Displays the running configuration for Fabric Extenders.