Information About the Cisco Nexus 2000 Series Fabric Extender
The
Cisco Nexus 2000 Series Fabric
Extender,
also known as FEX, is a highly scalable and
flexible server networking solution that works with
Cisco Nexus Series
devices to provide high-density, low-cost connectivity for server aggregation.
Scaling across 1-Gigabit Ethernet, 10-Gigabit Ethernet, unified fabric, rack,
and blade server environments, the
Fabric Extender
is designed to simplify data center architecture and operations.
The
Fabric Extender
integrates with its parent switch, which is a
Cisco Nexus Series
device, to allow automatic provisioning and configuration taken from the
settings on the parent device. This integration allows large numbers of servers
and hosts to be supported by using the same feature set as the parent device,
including security and quality-of-service (QoS) configuration parameters, with
a single management domain. The
Fabric Extender
and its parent switch enable a large multipath, loop-free, active-active data
center topology without the use of the Spanning Tree Protocol (STP).
Figure 1. Single Management Domain
The
Cisco Nexus 2000 Series Fabric
Extender
forwards all traffic to its parent
Cisco Nexus Series
device over 10-Gigabit Ethernet fabric uplinks, which allows all traffic to be
inspected by policies established on the
Cisco Nexus Series
device.
No software is included with the
Fabric Extender.
The software is automatically downloaded and upgraded from its parent device.
Fabric Extender Terminology
Some terms used in this document are as follows:
Fabric interface—A 10-Gigabit Ethernet uplink port that is designated for
connection from the
Fabric Extender
to its parent switch. A fabric interface cannot be used for any other purpose.
It must be directly connected to the parent switch.
Note
A fabric interface includes the corresponding interface on the
parent switch. This interface is enabled when you enter the
switchport mode fex-fabric command.
Port channel fabric interface—A port channel uplink connection
from the
Fabric Extender
to its parent switch. This connection consists of fabric interfaces that are bundled
into a single logical channel.
Host interface—An Ethernet host interface for connection to a
server or host system.
Note
Do not connect a bridge or switch to a host interface. These
interfaces are designed to provide end host or server connectivity.
Port channel host interface—A port channel host interface for connection to a
server or host system.
Fabric Extender Features
The
Cisco Nexus 2000 Series Fabric Extender allows a single switch—and a
single consistent set of switch features—to be supported across a large number
of hosts and servers. By supporting a large server-domain under a single
management entity, policies can be enforced more efficiently.
Some of the features of the parent switch cannot be extended onto the
Fabric Extender.
The Fabric Extender provides connectivity for computer hosts and other edge devices in the network fabric.
Follow these guidelines when connecting devices to Fabric Extender host interfaces:
All Fabric Extender host interfaces run as spanning tree edge ports with BPDU Guard enabled and you cannot configure them as spanning tree network ports.
You can connect servers that use active/standby teaming, 802.3ad port channels, or other host-based link redundancy mechanisms to Fabric Extender host interfaces.
Any device that is running spanning tree connected to a Fabric Extender host interface results in that host interface being placed in an error-disabled state when a BPDU is received.
You can connect any edge switch that leverages a link redundancy mechanism not dependent on spanning tree such as Cisco FlexLink or vPC (with the BPDU Filter enabled) to a Fabric Extender host interface. Because spanning tree is not used to eliminate loops, you should ensure a loop-free topology below the Fabric Extender host interfaces.
You can enable host interfaces to accept Cisco Discovery Protocol (CDP) packets. This protocol only
works when it is enabled for both ends of a link.
Note
CDP is not supported on fabric interfaces when the Fabric Extender is configured in a virtual port channel (vPC) topology.
Ingress and egress packet counters are provided on each host interface.
The following fabric extenders support port channel host interface configurations. Up to eight interfaces can be combined in a port channel. The port channel can be configured with or without Link Aggregation Control Protocol (LACP).
Cisco Nexus 2248TP
Cisco Nexus 2232PP
Cisco Nexus 2224TP
Cisco Nexus 2248PQ
Cisco Nexus B22 Fabric Extender for Fujitsu (N2K-B22FTS-P)
Cisco Nexus B22 Fabric Extender for HP (N2K-B22HP-P)
VLANs and Private VLANs
The
Fabric Extender supports Layer 2 VLAN trunks and IEEE 802.1Q VLAN encapsulation. Host interfaces can be members of private VLANs with the following restrictions:
You can configure a host interface as an isolated or community access port only.
You cannot configure a host interface as a promiscuous port.
You cannot configure a host interface as a private VLAN trunk port.
For more information about VLANs, see the chapter in this guide on Configuring VLANs.
Virtual Port Channels
With a virtual port channel (vPC), you can
configure topologies where a
Cisco Nexus Fabric Extender
is connected to a pair of
parent
switches or a pair of
Fabric Extenders are connected to a single parent switch.
The vPC can provide multipath connections, which allow you to create
redundancy between the nodes on your network.
Note
A port channel between two FEXs that are connected to the same Cisco Nexus device is not supported. Virtual port channels (vPCs) cannot span two different FEXs when connected to the same Cisco Nexus device.
The following vPC topologies are possible with
the
Fabric Extender:
The
parent
switches are connected single homed to
Fabric Extenders
that are subsequently connected to servers with dual interfaces (see the following figure).
Figure 2. Single Homed Fabric Extender vPC Topology
The
Fabric Extender
is connected dual homed to two upstream
parent
switches and connected downstream to single homed servers (see the following figure).
Figure 3.
Dual Homed Fabric Extender
vPC Topology
This configuration is also called an Active-Active topology.
Note
Port channels between two Fabric Extenders connected to the same Cisco Nexus device is not supported vPCs cannot span two different Fabric Extenders that are connected to the same physical Cisco Nexus device.
Fibre Channel over Ethernet Support
The Cisco Nexus 2232PP and Cisco Nexus 2248PQ support Fibre Channel over Ethernet (FCoE) with the following restrictions:
Only FCoE Initialization Protocol (FIP) enabled converged network adapters (CNAs) are supported on the Fabric Extender.
Binding to a port channel is limited to only one member in the port channel.
To reduce the load on the control plane of the Cisco Nexus Series device, Cisco NX-OS allows you to offload link-level protocol processing to the Fabric Extender CPU. The following protocols are
supported:
Link Layer Discovery Protocol (LLDP) and Data Center Bridging Exchange (DCBX)
Cisco Discovery Protocol (CDP)
Link Aggregation Control Protocol (LACP)
Quality of Service
The
Fabric Extender
provides two user queues for its quality-of-service (QoS) support, one for all
no-drop classes and one for all drop classes. The classes configured on its
parent switch are mapped to one of these two queues; traffic for no-drop
classes is mapped to one queue and traffic for all drop classes is mapped to
the other. Egress policies are also restricted to these two classes.
The Cisco Nexus Series device provides two predefined type qos class maps for matching
broadcast or multicast traffic; class-all-flood and class-ip-multicast. These
classes are ignored on the
Fabric Extender.
The
Fabric Extender
uses IEEE 802.1p class of service (CoS) values to associate traffic with the
appropriate class. Per-port quality of service (QoS) configuration and CoS-based egress queuing are
also supported.
Host interfaces support pause frames, which are implemented using IEEE 802.3x
link-level flow control (LLC). By default, flow control send is on and flow
control receive is off on all host interfaces. Autonegotiation is enabled on
the host interfaces. Per-class flow control is set according to the QoS
classes.
Host interfaces support jumbo frames (up to 9216 bytes); however, a
per-host interface maximum transmission unit (MTU) is not supported. Instead,
MTU is set according to the QoS classes. You modify MTU by setting policy and
class maps on the parent switch. Because the
Fabric Extender
has only two user queues, the MTU for the drop-queue is set to the maximum MTU
of all drop classes and the MTU on the no-drop queue is set to the maximum MTU
of all no-drop classes.
For more information about LLC and quality-of-service, see the Quality of Service Configuration Guide for your device.
Access Control Lists
The
Fabric Extender supports the full range of ingress access control lists (ACLs) that are available on its parent Cisco Nexus Series device.
For more information about ACLs, see the Security Configuration Guide for your device.
IGMP Snooping
IGMP snooping is supported on all host interfaces of the
Fabric Extender.
The
Fabric Extender
and its parent switch support IGMPv3 snooping based only on the destination
multicast MAC address. It does not support snooping that is based on the source MAC
address or on proxy reports.
You can configure the host interfaces on the
Fabric Extender
as Switched Port Analyzer (SPAN) source ports. You cannot configure
Fabric Extender
ports as a SPAN destination. Only one SPAN session is
supported for all the host interfaces on the same
Fabric Extender.
Ingress source (Rx), egress source (Tx), or both ingress and egress monitoring
are supported.
Note
All IP multicast traffic on the VLANs that a
Fabric Extender
host interface belongs to is captured in the SPAN session. You cannot separate the traffic by IP multicast group membership.
If you configure ingress monitoring and egress monitoring for host interfaces
on the same
Fabric Extender,
you might see a packet twice: once as the packet ingresses on an interface with
Rx configured, and again as the packet egresses on an interface with Tx
configured.
For more information about SPAN, see the System Management Configuration Guide for your device.
Fabric Interface Features
The
FEX
fabric interfaces support static port channels and priority flow control (PFC).
PFC allows you to apply pause functionality to specific classes of traffic on
an interface (instead of all the traffic on the interface). During the initial
discovery and association process, SFP+ validation and digital optical
monitoring (DOM) are performed as follows:
The FEX performs a local check on the uplink SFP+ transceiver. If it fails the security
check, the LED flashes but the link is still allowed to come up.
The
FEX
local check is bypassed if it is running its backup image.
The parent switch performs SFP validation again when the fabric
interface is brought up. It keeps the fabric interface down if SFP validation
fails.
After an interface on the parent switch is configured in fex-fabric
mode, all other features that were configured on that port and are not relevant
to this mode are deactivated. If the interface is reconfigured to remove
fex-fabric mode, the previous configurations are reactivated.
Note
Per class flow control mode is enabled by default on the fabric
interfaces. When a fabric interface is configured on the parent switch, PFC
mode is enabled by default and cannot be changed.
Note
For a 2248PQ, all fabric interfaces need to be bundled into a single fabric port channel. They cannot be used to connect the parent switch as individual ports.
For more information about PFC, see the Quality of Service Configuration Guide for your device.
Oversubscription
In a switching environment, oversubscription is the practice of
connecting multiple devices to the same interface to optimize port usage. An
interface can support a connection that runs at its maximum speed. Because
most interfaces do not run at their maximum speeds, you can take advantage of
unused bandwidth by sharing ports. Oversubscription, which is a function of the available fabric interfaces to
active host interfaces, provides cost-effective scalability and flexibility for
Ethernet environments.
The
Cisco Nexus 2148TFabric Extender
has 4 10-Gigabit Ethernet fabric interfaces and 48 1000BASE-T (1-Gigabit) Ethernet
host interfaces. With this system, you can have any number of configurations.
For example, you can configure the following:
No oversubscription (40 host interfaces for four fabric
interfaces)
1.2 to 1 oversubscription (48 host interfaces for four fabric
interfaces)
4.8 to 1 oversubscription (48 host interfaces for one fabric
interface)
The
Cisco Nexus 2248TPFabric Extender
has 4 10-Gigabit Ethernet fabric interfaces and 48 100/1000BASE-T (100-Mb/1-Gigabit) Ethernet
host interfaces. When its host interfaces are running in Gigabit Ethernet mode, it offers similar configurations to the Cisco Nexus 2148T.
The
Cisco Nexus 2248TP can be run with no oversubscription when its host interfaces are running in 100-Mb mode.
The Cisco Nexus 2248PQ Fabric Extender has 16 10-Gigabit Ethernet fabric interfaces and 48 10-Gigabit Ethernet host interfaces. All host interfaces use all of the available fabric interfaces. (Static pinning is not supported. Port-channel mode is only supported on fabric interfaces.) When all host interfaces are sending traffic to all fabric interfaces, the maximum oversubscription ratio for the Cisco Nexus 2248PQ is 3:1.
The Cisco Nexus 2232PPFabric Extender has 8 10-Gigabit Ethernet fabric interfaces and 32 10-Gigabit Ethernet host interfaces. All host interfaces use all of the available fabric interfaces. When all host interfaces are sending traffic to all fabric interfaces, the maximum oversubscription ratio for the Cisco Nexus 2232PP is 4:1.
The Cisco Nexus 2232TMFabric Extender has 8 10-Gigabit Ethernet fabric interfaces and 32 10G-BASE-T (10-Gigabit) Ethernet host interfaces. With this system, you can configure a 4 to 1 oversubscription (4 host interfaces for one fabric interface) or higher.
The Cisco Nexus 2224TPFabric Extender has 2 10-Gigabit Ethernet fabric interfaces and 24 100/1000BASE-T (100-Mb/1-Gigabit) Ethernet host interfaces. With this system, you can configure a 1.2 to 1 oversubscription (24 host interfaces for two fabric
interfaces) or higher.
The Cisco Nexus B22 Fabric Extender for HP (NB22HP) has 8 10-Gigabit Ethernet fabric interfaces and 16 1G/10-Gigabit Ethernet host interfaces. All host interfaces use all of the available fabric interfaces. Static pinning and port-channel mode are supported. When all host interfaces are sending traffic to all fabric interfaces, the maximum oversubscription ratio for the Cisco Nexus B22 Fabric Extender for HP (N2K-B22HP-P) is 2:1.
The Cisco Nexus B22 Fabric Extender for Fujitsu (NB22FTS) has 8 10-Gigabit Ethernet fabric interfaces and 16 10-Gigabit Ethernet host interfaces. All host interfaces use all of the available fabric interfaces. Static pinning and port-channel mode are supported. When all host interfaces are sending traffic to all fabric interfaces, the maximum oversubscription ratio for the Cisco Nexus B22 Fabric Extender for Fujitsu (N2K-B22FTS-P) is 2:1.
Management Model
The
Cisco Nexus 2000 Series Fabric
Extender
is managed by its parent switch over the fabric interfaces through a zero-touch
configuration model. The switch discovers
the Fabric Extender by detecting the fabric interfaces of the
Fabric Extender.
After discovery, if the
Fabric Extender
has been correctly associated with the parent switch, the following operations
are performed:
The switch checks the software image compatibility and upgrades
the
Fabric Extender
if necessary.
The switch and
Fabric Extender
establish in-band IP connectivity with each other. The switch assigns an IP
address in the range of loopback addresses (127.15.1.0/24) to the
Fabric Extender
to avoid conflicts with IP addresses that might be in use on the network.
The switch pushes the configuration data to the
Fabric Extender.
The
Fabric Extender
does not store any configuration locally.
The
Fabric Extender
updates the switch with its operational status. All
Fabric Extender
information is displayed using the switch commands for monitoring and
troubleshooting.
Forwarding Model
The
Cisco Nexus 2000 Series Fabric
Extender
does not perform any local switching. All traffic is sent to the parent switch
that provides central forwarding and policy enforcement, including host-to-host
communications between two systems that are connected to the same
Fabric Extender
as shown in the following figure.
Figure 4. Forwarding Model
The forwarding model facilitates feature consistency between the
Fabric Extender
and its parent Cisco Nexus Series device.
Note
The
Fabric Extender
provides end-host connectivity into the network fabric. As a result, BPDU Guard is enabled on all its host interfaces. If you
connect a bridge or switch to a host interface, that interface is placed in an
error-disabled state when a BPDU is received.
You cannot disable BPDU Guard on the host interfaces of the
Fabric Extender.
The
Fabric Extender
supports egress multicast replication from the network to the host. Packets
that are sent from the parent switch for multicast addresses attached to the
Fabric Extender
are replicated by the
Fabric Extender
ASICs and are then sent to corresponding hosts.
Connection Model
Two methods (the static pinning fabric interface connection and the Port Channel fabric interface connection) allow the traffic from an end host to the parent switch to be distributed when going through the
Cisco Nexus 2000 Series Fabric
Extender.
Note
The Cisco Nexus 2248PQ Fabric Extender does not support the static pinning fabric interface connection.
To provide a deterministic relationship between the host interfaces
and the parent switch, you can configure the
Fabric Extender
to use individual fabric interface connections. This configuration connects the
10-Gigabit Ethernet fabric interfaces as shown in the following figure. You can
use any number of fabric interfaces up to the maximum available on the model of
the
Fabric Extender.
When the
Fabric Extender
is brought up, its host interfaces are distributed equally among the available
fabric interfaces. As a result, the bandwidth that is dedicated to each end
host toward the parent switch is never changed by the switch but instead is
always specified by you.
Note
If a fabric interface fails, all its associated host interfaces are
brought down and remain down until the fabric interface is restored.
You must use the
pinning max-links command to create a number of
pinned fabric interface connections so that the parent switch can determine a
distribution of host interfaces. The host interfaces are divided by the number
of the max-links and distributed accordingly. The default value is max-links 1.
Caution
Changing the value of the max-links is disruptive; all the host
interfaces on the
Fabric Extender
are brought down and back up as the parent switch reassigns its static pinning.
The pinning order of the host interfaces is initially determined by
the order in which the fabric interfaces were configured. When the parent
switch is restarted, the configured fabric interfaces are pinned to the host
interfaces in an ascending order by the port number of the fabric interface.
To guarantee a deterministic and sticky association across a reboot,
you can manually redistribute the pinning.
Note
The redistribution of the host interfaces will always be in an
ascending order by the port number of the fabric interface.
Port Channel Fabric Interface Connection
To provide load balancing between the host interfaces and the parent
switch, you can configure the
Fabric Extender
to use a port channel fabric interface connection. This connection bundles
10-Gigabit Ethernet fabric interfaces into a single logical channel as shown in
the following figure.
Figure 6. Port Channel Fabric Interface Connection
When you configure the
Fabric Extender
to use a port channel fabric interface connection to its parent switch, the
switch load balances the traffic from the hosts that are connected to the host
interface ports by using the following load-balancing criteria to select the
link:
For a Layer 2 frame, the switch uses the source and destination
MAC addresses.
For a Layer 3 frame, the switch uses the source and destination
MAC addresses and the source and destination IP addresses.
Note
A fabric interface that fails in the port channel does not trigger a
change to the host interfaces. Traffic is automatically redistributed across
the remaining links in the port channel fabric interface.
If all links in the fabric port channel go down, all host interfaces on the FEX are set to the down state.
Port Numbering Convention
The following port numbering convention is used for the
Fabric Extender:
interfaceethernetchassis/slot/QSFP-module/port
where
chassis is configured by the
administrator. A
Fabric Extender
must be directly connected to its parent Cisco Nexus Series device via individual fabric
interfaces or a port channel fabric interface. You configure a chassis ID on a
physical Ethernet interface or port channel on the switch to identify the
Fabric Extender
that is discovered through those interfaces.
The chassis ID ranges from 100 to 199.
Note
The chassis ID is required only to access a host interface on
the
Fabric Extender.
A value of less than 100 indicates a slot on the parent switch. The following
port numbering convention is used for the interfaces on the switch:
interfaceethernetslot/port
slot identifies the slot number on the
Fabric Extender.
QSFP-module identifies the 10G breakout Linecard Expansion Module (LEM).
port identifies the port number on a
specific slot and chassis ID.
Fabric Extender Image Management
No software ships with the
Cisco Nexus 2000 Series Fabric
Extender.
The
Fabric Extender
image is bundled into the system image of the parent switch. The image is
automatically verified and updated (if required) during the association process
between the parent switch and the
Fabric Extender.
When you enter the
install all command, it upgrades the software on the parent
Cisco Nexus Series
switch and also upgrades the software on any attached
Fabric Extender.
To minimize downtime as much as possible, the
Fabric Extender
remains online while the installation process loads its new software image.
Once the software image has successfully loaded, the parent switch and the
Fabric Extender
both automatically reboot.
This process is required to maintain version
compatibility between the parent switch and the
Fabric Extender.
Fabric Extender Hardware
The
Cisco Nexus 2000 Series Fabric Extender architecture allows hardware configurations with various host interface counts and speeds.
The
Cisco Nexus 2000 Series Fabric Extender is a 1 RU chassis that is designed for rack mounting. The chassis supports redundant hot-swappable fans and power supplies.
Ethernet Interfaces
There are 8 models of the Cisco Nexus 2000 Series Fabric
Extender:
The
Cisco Nexus 2148T has 48 1000BASE-T Ethernet host interfaces for its downlink connection to servers or hosts and 4 10-Gigabit Ethernet fabric interfaces with SFP+ interface adapters for its uplink
connection to the parent switch.
The Cisco Nexus 2224TP has 24 100BASE-T/1000Base-T Ethernet host interfaces for its downlink connection to servers or hosts and 2 10-Gigabit Ethernet fabric interfaces with SFP+ interface adapters for its uplink
connection to the parent switch.
The Cisco Nexus 2248PQ has 48 10-Gigabit Ethernet host interfaces with SFP+ interface adapters and 16 10-Gigabit Ethernet fabric interfaces corresponding to 4 QSFP interface adapters for its uplink connection to the parent switch.
The Cisco Nexus 2232PP has 32 10-Gigabit Ethernet host interfaces with SFP+ interface adapters and 8 10-Gigabit Ethernet fabric interfaces with SFP+ interface adapters for its uplink
connection to the parent switch.
The Cisco Nexus 2248TP has 48 100BASE-T/1000Base-T Ethernet host interfaces for its downlink connection to servers or hosts and 4 10-Gigabit Ethernet fabric interfaces with SFP+ interface adapters for its uplink
connection to the parent switch.
The Cisco Nexus 2248TP-E has all the features of the Cisco Nexus 2248TP with these additional features:
A larger buffer to absorb large bursts.
Support for an ingress and egress queue-limit per port.
Support for debug counters.
Support for pause no-drop behavior over a cable distance of 3000 meters between the Fabric Extender and switch.
Support for a user configurable shared-buffer.
The Cisco Nexus B22 Fabric Extender for HP (NB22HP) has 16 1G/10-Gigabit Ethernet host interfaces. All host interfaces use all of the available fabric interfaces.
The Cisco Nexus B22 Fabric Extender for Fujitsu (NB22FTS) has 16 10-Gigabit Ethernet host interfaces. All host interfaces use all of the available fabric interfaces.
Associating a Fabric Extender to a Fabric Interface
A
FEX
is connected to its parent device through physical Ethernet interfaces or a port channel. By default, the parent device does not allow the attached
Fabric Extender
to connect until it has been assigned a FEX number and is associated with the
connected interface.
Note
The
Fabric Extender
may connect to the switch through a number of separate physical Ethernet
interfaces or one port channel interface.
Note
You must enable the Fabric Extender features with the feature fex command before you can configure and use a Fabric Extender that is connected to the parent switch.
As a best practice, only enter the fex associate command from the port channel interface, not from the physical interface.
If you try to associate a physical port to a FEX before that physical port is joined to a port channel, the physical port moves to the err-disable state and the Cisco Nexus Series device does not communicate with the FEX on that link. You must enter the shutdown command and the no shutdown command on the Ethernet interface (not the port channel interface) to clear the err-disable state and bring the link up. (Note that this does not apply if the configuration is performed prior to cabling.)
Note
When adding physical interfaces to port channels, all configurations on the port channel and physical interface must match.
This example shows how to display the association of the Fabric Extender and the parent device:
The parent Cisco Nexus Series device remembers the type of the Fabric Extender in its binary configuration. When this feature is configured, the Fabric Extender is allowed to come online only if its type matches the configured FEX type.
Step 6
no type
Example:
switch(config-fex)# no type
(Optional)
Deletes the FEX type. When a Fabric Extender is connected to the fabric interfaces and does not match the configured type that is saved in the binary configuration on the parent switch, all configurations for all interfaces on the Fabric Extender are deleted.
Step 7
pinning max-linksuplinks
Example:
switch(config-fex)# pinning max-links 2
(Optional)
Defines the number of uplinks. The default is 1. The range is from
1 to 4.
This command is only applicable if the
Fabric Extender
is connected to its parent switch using one or more statically pinned fabric
interfaces. There can only be one port channel connection.
Caution
Changing the number of uplinks with the
pinning max-links command disrupts all the
host interface ports of the
Fabric Extender.
Step 8
no pinning max-links
Example:
switch(config-fex)# no pinning max-links
(Optional)
Resets the number of uplinks to the default.
Caution
Changing the number of uplinks with the
no pinning max-links command disrupts all the
host interface ports of the
Fabric Extender.
Step 9
serialserial
Example:
switch(config-fex)# serial JAF1339BDSK
(Optional)
Defines a serial number string. If this command is configured,
a switch allows the corresponding chassis ID to associate (using
the
fex associate command) only if the
Fabric Extender
reports a matching serial number string.
Caution
Configuring a serial number that does not match the specified
Fabric Extender
forces the
Fabric Extender
offline.
Step 10
no serial
Example:
switch(config-fex)# no serial
(Optional)
Deletes the serial number string.
Enabling the Fabric Extender Locator LED
The locator beacon LED on the Fabric Extender allows you to locate a specific Fabric Extender in a rack.
Procedure
Command or Action
Purpose
Step 1
locator-led fexFEX-number
Example:
switch# locator-led fex 101
Turns on the locator beacon LED for a specific Fabric Extender.
Step 2
no locator-led fexFEX-number
Example:
switch# no locator-led fex 101
(Optional)
Turns off the locator beacon LED for a specific Fabric Extender.
Redistributing the Links
When you provision the
Fabric Extender with statically pinned interfaces, the downlink host interfaces on the
Fabric Extender are pinned to the fabric interfaces in the order that they were initially configured. If you want to maintain a specific relationship of host interfaces to fabric interface across reboots, you should repin the links.
You may want to perform this function in these two situations:
A change in the max-links configuration.
If you need to maintain the pinning order of host interfaces to fabric interfaces.
Note
The Cisco Nexus 2248PQ Fabric Extender does not support the static pinning fabric interface connection.
If you initially configured a specific port on the parent switch, for example port 33, as your only
fabric interface, all 48 host interfaces are pinned to this port. If you
provision another port, for example 35, you must enter the
pinning max-links 2 command to redistribute the host
interfaces. All host interfaces are brought down and host interfaces 1 to 24
are pinned to fabric interface 33 and host interfaces 25 to 48 are pinned to
fabric interface 35.
Maintaining the Pinning Order
The pinning order of the host interfaces is initially determined by
the order in which the fabric interfaces were configured. In this example, four
fabric interfaces were configured in the following order:
The next time that you reboot the
Fabric Extender,
the configured fabric interfaces are pinned to the host interfaces in an
ascending order by port number of the fabric interface. If you want to
configure the same fixed distribution of host interfaces without restarting the
Fabric Extender,
enter the
fex pinning redistribute command.
Redistributes the host connections. The range of the FEX-number
is from 100 to 199.
Verifying the Fabric Extender Configuration
Use the following commands to display configuration information about the defined interfaces
on a
Fabric Extender.
Command or Action
Purpose
show fex [FEX-number]
[detail]
Displays information about a specific
Fabric Extender
or all attached units.
show interfacetypenumberfex-intf
Displays the
Fabric Extender
ports that are pinned to a specific switch interface.
show interface fex-fabric
Displays the switch interfaces that have detected a
Fabric Extender
uplink.
show interface ethernetnumbertransceiver [fex-fabric]
Displays the SFP+ transceiver and diagnostic optical
monitoring (DOM) information for the
Fabric Extender
uplinks.
showfeature-set
Displays the status of the feature sets on the device.
Configuration Examples for the Fabric Extender
This example shows how to display all the attached
Fabric Extender
units:
switch# show fex
FEX FEX FEX FEX
Number Description State Model Serial
------------------------------------------------------------------------
100 FEX0100 Online N2K-C2248TP-1GE JAF1339BDSK
101 FEX0101 Online N2K-C2232P-10GE JAF1333ADDD
102 FEX0102 Online N2K-C2232P-10GE JAS12334ABC
This example shows how to display the detailed status of a specific
Fabric Extender:
switch# show fex 100 detail
FEX: 100 Description: FEX0100 state: Online
FEX version: 5.0(2)N1(1) [Switch version: 5.0(2)N1(1)]
FEX Interim version: 5.0(2)N1(0.205)
Switch Interim version: 5.0(2)N1(0.205)
Extender Model: N2K-C2224TP-1GE, Extender Serial: JAF1427BQLG
Part No: 73-13373-01
Card Id: 132, Mac Addr: 68:ef:bd:62:2a:42, Num Macs: 64
Module Sw Gen: 21 [Switch Sw Gen: 21]
post level: complete
pinning-mode: static Max-links: 1
Fabric port for control traffic: Eth1/29
Fabric interface state:
Po100 - Interface Up. State: Active
Eth1/29 - Interface Up. State: Active
Eth1/30 - Interface Up. State: Active
Fex Port State Fabric Port Primary Fabric
Eth100/1/1 Up Po100 Po100
Eth100/1/2 Up Po100 Po100
Eth100/1/3 Up Po100 Po100
Eth100/1/4 Up Po100 Po100
Eth100/1/5 Up Po100 Po100
Eth100/1/6 Up Po100 Po100
Eth100/1/7 Up Po100 Po100
Eth100/1/8 Up Po100 Po100
Eth100/1/9 Up Po100 Po100
Eth100/1/10 Up Po100 Po100
Eth100/1/11 Up Po100 Po100
Eth100/1/12 Up Po100 Po100
Eth100/1/13 Up Po100 Po100
Eth100/1/14 Up Po100 Po100
Eth100/1/15 Up Po100 Po100
Eth100/1/16 Up Po100 Po100
Eth100/1/17 Up Po100 Po100
Eth100/1/18 Up Po100 Po100
Eth100/1/19 Up Po100 Po100
Eth100/1/20 Up Po100 Po100
Eth100/1/21 Up Po100 Po100
Eth100/1/22 Up Po100 Po100
Eth100/1/23 Up Po100 Po100
Eth100/1/24 Up Po100 Po100
Eth100/1/25 Up Po100 Po100
Eth100/1/26 Up Po100 Po100
Eth100/1/27 Up Po100 Po100
Eth100/1/28 Up Po100 Po100
Eth100/1/29 Up Po100 Po100
Eth100/1/30 Up Po100 Po100
Eth100/1/31 Up Po100 Po100
Eth100/1/32 Up Po100 Po100
Eth100/1/33 Up Po100 Po100
Eth100/1/34 Up Po100 Po100
Eth100/1/35 Up Po100 Po100
Eth100/1/36 Up Po100 Po100
Eth100/1/37 Up Po100 Po100
Eth100/1/38 Up Po100 Po100
Eth100/1/39 Up Po100 Po100
Eth100/1/40 Down Po100 Po100
Eth100/1/41 Up Po100 Po100
Eth100/1/42 Up Po100 Po100
Eth100/1/43 Up Po100 Po100
Eth100/1/44 Up Po100 Po100
Eth100/1/45 Up Po100 Po100
Eth100/1/46 Up Po100 Po100
Eth100/1/47 Up Po100 Po100
Eth100/1/48 Up Po100 Po100
Logs:
02/05/2010 20:12:17.764153: Module register received
02/05/2010 20:12:17.765408: Registration response sent
02/05/2010 20:12:17.845853: Module Online Sequence
02/05/2010 20:12:23.447218: Module Online
This example shows how to display the
Fabric Extender
interfaces pinned to a specific switch interface:
This example shows how to display the switch interfaces that are
connected to a
Fabric Extender
uplink:
switch# show interface fex-fabric
Fabric Fabric Fex FEX
Fex Port Port State Uplink Model Serial
---------------------------------------------------------------
100 Eth1/29 Active 3 N2K-C2248TP-1GE JAF1339BDSK
100 Eth1/30 Active 4 N2K-C2248TP-1GE JAF1339BDSK
102 Eth1/33 Active 1 N2K-C2232P-10GE JAS12334ABC
102 Eth1/34 Active 2 N2K-C2232P-10GE JAS12334ABC
102 Eth1/35 Active 3 N2K-C2232P-10GE JAS12334ABC
102 Eth1/36 Active 4 N2K-C2232P-10GE JAS12334ABC
101 Eth1/37 Active 5 N2K-C2232P-10GE JAF1333ADDD
101 Eth1/38 Active 6 N2K-C2232P-10GE JAF1333ADDD
101 Eth1/39 Active 7 N2K-C2232P-10GE JAF1333ADDD
101 Eth1/40 Active 8 N2K-C2232P-10GE JAF1333ADDD
This example shows how to display the SFP+ transceiver and diagnostic
optical monitoring (DOM) information for
Fabric Extender
uplinks for an SFP+ transceiver that
is plugged into the parent switch interface:
switch# show interface ethernet 1/40 transceiver
Ethernet1/40
sfp is present
name is CISCO-MOLEX INC
part number is 74752-9026
revision is A0
serial number is MOC13321057
nominal bitrate is 12000 MBits/sec
Link length supported for copper is 3 m(s)
cisco id is --
cisco extended id number is 4
This example shows how to display the SFP+ transceiver and DOM information for
Fabric Extender
uplinks for an SFP+ transceiver that
is plugged into the uplink port on the
Fabric Extender:
switch# show interface ethernet 1/40 transceiver fex-fabric
Ethernet1/40
sfp is present
name is CISCO-MOLEX INC
part number is 74752-9026
revision is A0
serial number is MOC13321057
nominal bitrate is 12000 MBits/sec
Link length supported for 50/125mm fiber is 0 m(s)
Link length supported for 62.5/125mm fiber is 0 m(s)
cisco id is --
cisco extended id number is 4
Verifying the Chassis Management Information
Use the following to display configuration information used on the switch
supervisor to manage the
Fabric Extender.
Command or Action
Purpose
show diagnostic result fexFEX-number
Displays results from the diagnostic test for a
Fabric Extender.
show environment fex {all |
FEX-number} [temperature |
power |
fan]
Displays the environmental sensor status.
show inventory fexFEX-number
Displays inventory information for a
Fabric Extender.
show module fexFEX-number
Displays module information about a
Fabric Extender.
show sprom fexFEX-number {all |
backplane |
powersupplyps-num} |
all
Displays the contents of the serial PROM (SPROM) on the
Fabric Extender.
Configuration Examples for Chassis Management
This example shows how to display the module information about all
connected
Fabric Extender
units:
switch# show module fex
FEX Mod Ports Card Type Model Status.
--- --- ----- ---------------------------------- ------------------ -----------
100 1 48 Fabric Extender 48x1GE + 4x10G Mod N2K-C2248TP-1GE present
101 1 32 Fabric Extender 32x10GE + 8x10G Mo N2K-C2232P-10GE present
102 1 32 Fabric Extender 32x10GE + 8x10G Mo N2K-C2232P-10GE present
FEX Mod Sw Hw World-Wide-Name(s) (WWN)
--- --- -------------- ------ -----------------------------------------------
100 1 4.2(1)N1(1) 0.103 --
101 1 4.2(1)N1(1) 1.0 --
102 1 4.2(1)N1(1) 1.0 --
FEX Mod MAC-Address(es) Serial-Num
--- --- -------------------------------------- ----------
100 1 000d.ece3.2800 to 000d.ece3.282f JAF1339BDSK
101 1 000d.ecca.73c0 to 000d.ecca.73df JAF1333ADDD
102 1 000d.ecd6.bec0 to 000d.ecd6.bedf JAS12334ABC
This example shows how to display the module information about a
specific
Fabric Extender:
switch# show module fex 100
FEX Mod Ports Card Type Model Status.
--- --- ----- ---------------------------------- ------------------ -----------
100 1 48 Fabric Extender 48x1GE + 4x10G Mod N2K-C2248TP-1GE present
FEX Mod Sw Hw World-Wide-Name(s) (WWN)
--- --- -------------- ------ -----------------------------------------------
100 1 4.2(1)N1(1) 0.103 --
FEX Mod MAC-Address(es) Serial-Num
--- --- -------------------------------------- ----------
100 1 000d.ece3.2800 to 000d.ece3.282f JAF1339BDSK
This example shows how to display the inventory information about a
specific
Fabric Extender:
This example shows how to display the environment status for a
specific
Fabric Extender:
switch# show environment fex 101
Temperature Fex 101:
-----------------------------------------------------------------
Module Sensor MajorThresh MinorThres CurTemp Status
(Celsius) (Celsius) (Celsius)
-----------------------------------------------------------------
1 Outlet-1 60 50 33 ok
1 Outlet-2 60 50 38 ok
1 Inlet-1 50 40 35 ok
1 Die-1 100 90 44 ok
Fan Fex: 101:
------------------------------------------------------
Fan Model Hw Status
------------------------------------------------------
Chassis N2K-C2148-FAN -- ok
PS-1 -- -- absent
PS-2 NXK-PAC-400W -- ok
Power Supply Fex 101:
---------------------------------------------------------------------------
Voltage: 12 Volts
-----------------------------------------------------
PS Model Power Power Status
(Watts) (Amp)
-----------------------------------------------------
1 -- -- -- --
2 NXK-PAC-400W 4.32 0.36 ok
Mod Model Power Power Power Power Status
Requested Requested Allocated Allocated
(Watts) (Amp) (Watts) (Amp)
--- ------------------- ------- ---------- --------- ---------- ----------
1 N2K-C2248TP-1GE 0.00 0.00 0.00 0.00 powered-up
Power Usage Summary:
--------------------
Power Supply redundancy mode: redundant
Total Power Capacity 4.32 W
Power reserved for Supervisor(s) 0.00 W
Power currently used by Modules 0.00 W
-------------
Total Power Available 4.32 W
-------------
This example shows how to display the SPROM for a specific
Fabric Extender:
switch# show sprom fex 101 all
DISPLAY FEX 101 SUP sprom contents
Common block:
Block Signature : 0xabab
Block Version : 3
Block Length : 160
Block Checksum : 0x1a1e
EEPROM Size : 65535
Block Count : 3
FRU Major Type : 0x6002
FRU Minor Type : 0x0
OEM String : Cisco Systems, Inc.
Product Number : N2K-C2248TP-1GE
Serial Number : JAF1339BDSK
Part Number : 73-12748-01
Part Revision : 11
Mfg Deviation : 0
H/W Version : 0.103
Mfg Bits : 0
Engineer Use : 0
snmpOID : 9.12.3.1.9.78.3.0
Power Consump : 1666
RMA Code : 0-0-0-0
CLEI Code : XXXXXXXXXTBDV00
VID : V00
Supervisor Module specific block:
Block Signature : 0x6002
Block Version : 2
Block Length : 103
Block Checksum : 0x2686
Feature Bits : 0x0
HW Changes Bits : 0x0
Card Index : 11016
MAC Addresses : 00-00-00-00-00-00
Number of MACs : 0
Number of EPLD : 0
Port Type-Num : 1-48;2-4
Sensor #1 : 60,50
Sensor #2 : 60,50
Sensor #3 : -128,-128
Sensor #4 : -128,-128
Sensor #5 : 50,40
Sensor #6 : -128,-128
Sensor #7 : -128,-128
Sensor #8 : -128,-128
Max Connector Power: 4000
Cooling Requirement: 65
Ambient Temperature: 40
DISPLAY FEX 101 backplane sprom contents:
Common block:
Block Signature : 0xabab
Block Version : 3
Block Length : 160
Block Checksum : 0x1947
EEPROM Size : 65535
Block Count : 5
FRU Major Type : 0x6001
FRU Minor Type : 0x0
OEM String : Cisco Systems, Inc.
Product Number : N2K-C2248TP-1GE
Serial Number : SSI13380FSM
Part Number : 68-3601-01
Part Revision : 03
Mfg Deviation : 0
H/W Version : 1.0
Mfg Bits : 0
Engineer Use : 0
snmpOID : 9.12.3.1.3.914.0.0
Power Consump : 0
RMA Code : 0-0-0-0
CLEI Code : XXXXXXXXXTDBV00
VID : V00
Chassis specific block:
Block Signature : 0x6001
Block Version : 3
Block Length : 39
Block Checksum : 0x2cf
Feature Bits : 0x0
HW Changes Bits : 0x0
Stackmib OID : 0
MAC Addresses : 00-0d-ec-e3-28-00
Number of MACs : 64
OEM Enterprise : 0
OEM MIB Offset : 0
MAX Connector Power: 0
WWN software-module specific block:
Block Signature : 0x6005
Block Version : 1
Block Length : 0
Block Checksum : 0x66
wwn usage bits:
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00
00 00
License software-module specific block:
Block Signature : 0x6006
Block Version : 1
Block Length : 16
Block Checksum : 0x86f
lic usage bits:
ff ff ff ff ff ff ff ff
DISPLAY FEX 101 power-supply 2 sprom contents:
Common block:
Block Signature : 0xabab
Block Version : 3
Block Length : 160
Block Checksum : 0x1673
EEPROM Size : 65535
Block Count : 2
FRU Major Type : 0xab01
FRU Minor Type : 0x0
OEM String : Cisco Systems Inc NXK-PAC-400W
Product Number : NXK-PAC-400W
Serial Number : LIT13370QD6
Part Number : 341
Part Revision : -037
CLEI Code : 5-01 01 000
VID : 000
snmpOID : 12336.12336.12336.12336.12336.12336.12374.12336
H/W Version : 43777.2
Current : 36
RMA Code : 200-32-32-32
Power supply specific block:
Block Signature : 0x0
Block Version : 0
Block Length : 0
Block Checksum : 0x0
Feature Bits : 0x0
Current 110v : 36
Current 220v : 36
Stackmib OID : 0
Configuring the Cisco Nexus N2248TP-E Fabric Extender
The Cisco Nexus 2248TP-E Fabric Extender supports all of the CLI commands of the Cisco Nexus 2248TP Fabric Extender with additional commands to configure the following:
Shared buffer (FEX global level)
Queue limit in ingress direction (FEX global level and interface level)
Queue limit in egress direction (FEX global level and interface level)
No drop class over a distance of 3000 meters between the FEX and switch (FEX global level)
The following are guidelines for the configuration of the shared buffer:
Configuring the shared buffer is done at the FEX global level.
The total available buffer is 32 MB which is shared in both the ingress and egress directions.
The default size of the shared buffer is 25392KB.
However, when configuring an Ethernet-based pause no-drop class, the shared buffer size changes to 10800 KB. This change is required to increase the dedicated buffer that supports the pause no-drop class. The pause no-drop class does not use buffer space from the shared-pool.
Note
Performing these commands might result in traffic disruption on all ports.
Configuring the Cisco Nexus N2248PQ Fabric Extender
The Cisco Nexus 2248PQ Fabric Extender supports all of the CLI commands of the Cisco Nexus 2248TP Fabric Extender with additional commands to configure the following:
Shared buffer (FEX global level)
Load-balancing queues (FEX global level)
No drop class over a distance of 3000 meters between the FEX and switch (FEX global level)