Re: ASK THE EXPERT - Nexus 5000 & 2000 series - Page 2

ciscomoderator · ‎02-25-2011

with Lucien Avramov

Welcome to the Cisco Networking Professionals Ask the Expert conversation. This is an opportunity to learn how to troubleshoot Nexus 5000 & 2000 series with Lucien Avramov. Lucien is a customer support engineer at the Cisco Technical Assistance Center. He currently works in the data center switching team supporting customers on the Cisco Nexus 5000 and 2000. He was previously a technical leader within the network management team. Lucien holds a bachelor's degree in general engineering and a master's degree in computer science from Ecole des Mines d'Ales. He also holds the following certifications: CCIE #19945 in Routing and Switching, CCDP, DCNIS, and VCP #66183.

Remember to use the rating system to let Lucien know if you have received an adequate response.

Lucien might not be able to answer each question due to the volume expected during this event. Remember that you can continue the conversation on the Security discussion forums shortly after the event. This event lasts through March 11, 2011. Visit this forum often to view responses to your questions and the questions of other community members.

xjullien84 · ‎03-08-2011

Hi Lucien,

I have 2 Nexus 5020 running NX-OS 5.0(2)N1(1) and 1 N2248..

The VPC architecture is: FEX Dual-Connected to N5K switches

VPC Peer link between both N5K is UP.

N5K ports connected to the N2K are in “"fex-fabric DOWN” reason= SDP timeout/SFP Mismatch

I’ve tried to configure the same ports in “access mode” and the port comes UP.

As soon as I configure them in “fex-fabric mode”, the ports go down.

Here is my N5K configuration:

int port-channel 102

description FEX-102

switchport mode fex-fabric

fex associate 102

vpc 102

int e1/20

description FEX-102

switchport mode fex-fabric

fex associate 102

channel-group 102

Can you help ?

Thanks ;-)

Xavière

Lucien Avramov · ‎03-08-2011

Thanks for your question. I assume you have only e1/20 connected on each N5K to this fex.

Can you make sure of the following, and feel free to attach the outputs back:

-show interface e1/20 transceiver details

I suspect you are not using matching SFPs on each N5K. You can use any supported SFP from the matrix, however we need them to match on each N5K when going to the same FEX.

http://www.cisco.com/en/US/docs/interfaces_modules/transceiver_modules/compatibility/matrix/OL_6974.html#wp55411

xjullien84 · ‎03-09-2011

Thx a lot !

SFP didn't match :-) It works now !

Xavière

apmorgan · ‎03-08-2011

Hello,

I am trying to extend the fabric from a 5020 to a 2248TP and 2232PP.

I have the fet-10g but my 5020 doesn't like it. Link light is orange on the 5020 port and off on the 2000 switches.

Eth1/17 -- sfpInvali 1 full 10G 10g
Eth1/18 -- sfpInvali 1 full 10G 10g

Ethernet1/17
    transceiver is present
    type is Fabric Extender Transceiver
    name is CISCO-FINISAR
    part number is FTLX8570D3BCL-C1
    revision is A
    serial number is ......

    nominal bitrate is 10300 MBit/sec
    Link length supported for 50/125um fiber is 20 m
    Link length supported for 50/125um fiber is 100 m
    Link length supported for 62.5/125um fiber is 10 m
    cisco id is --
    cisco extended id number is 4

           Transceiver Detail Diagnostics Information (internal calibration)
----------------------------------------------------------------------------
                Current              Alarms                  Warnings
                Measurement     High        Low         High          Low
----------------------------------------------------------------------------
Temperature   35.61 C        75.00 C      5.00 C     70.00 C       10.00 C
Voltage        3.27 V         3.63 V      2.97 V      3.46 V        3.13 V
Current        0.40 mA --   11.80 mA     4.00 mA    10.80 mA       5.00 mA
Tx Power      -14.81 dBm --    2.69 dBm -11.30 dBm   -1.30 dBm     -7.30 dBm

Rx Power N/A -- 2.99 dBm -13.97 dBm -1.00 dBm -9.91 dBm
----------------------------------------------------------------------------
Note: ++ high-alarm; + high-warning; -- low-alarm; - low-warning

FET-10G is documented to be support on the Nexus 5020 with the 2000 switches. I tried with NX-OS of 4.2 and latest 5.0.3 neither work.

Any ideas what is wrong?

Thanks

A.

Lucien Avramov · ‎03-08-2011

Have you configured the port as switchport mode fex-fabric? The FET-10G only works for this mode.

apmorgan · ‎03-09-2011

Thanks,

switchport mode fex-fabric

did the trick.

mleinio · ‎03-09-2011

Hi Lucien! Do you have any information if the SFP-10G-ER transceiver will be supported on Nexus 5548/5596 later (and if yes, when)? It seems not to be compatible at the moment according to http://www.cisco.com/en/US/docs/interfaces_modules/transceiver_modules/compatibility/matrix/OL_6974.html.

Markku

Lucien Avramov · ‎03-09-2011

You are correct SFP-10G-ER is not supported at this time on the 5500. It is being evaluated for support in future code releases, no more details to share as far as when at this time.

kerim mohammed · ‎03-09-2011

Hello Lucien,

I just want to know if ERSPAN is supported on the Nexus N5K-C5020P-BF which is running 5.0(2)N1(1). It seems the commands are there to set up ERSPAN source however the parameters like destination IP and source interfaces are not saved in and the ERSPAN indicates as being down.

Here is sample output:

D45-N5K1-25# sh monitor session 1
   session 1
---------------
type              : erspan-source
state             : down (No src/dst configured)
ERSPAN ID         : 100
ERSPAN TTL        : 3
ERSPAN IP Prec.   : 0
ERSPAN DSCP       : 0
ERSPAN MTU        : 1500
source intf       :
    rx            :
    tx            :
    both          :
    rx            :
destination IP    :

D45-N5K1-25#

Lucien Avramov · ‎03-09-2011

Thanks for asking. The issue is reported in CSCtn84269, you can view this in our bug tool kit page:

http://tools.cisco.com/Support/BugToolKit/action.do?hdnAction=searchBugs

Basically, in 5.0.2 code this shows in the parser, however the feature is still not supported. In 5.0.3 and later code, this has been removed from the parser and is not an option.

Rest assured, the feature ERSPAN is in the works but is just not yet released.

Pavel Dimow · ‎03-09-2011

Hi Lucien,

is it possible to have FEX 2148 connected to two Nexus 5k for redundancy? If I look at FEX like a linecard I think it's not possible but

can you confirm this please?

Tnx

Lucien Avramov · ‎03-09-2011

You can surely have a FEX (2148) or any other model dual homed to two Nexus 5ks.

To achieve such you need to configure vPC (virtual port-channel).

Here is a quick start guide:

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9670/configuration_guide_c07-543563.html

And a step by step video:

https://supportforums.cisco.com/videos/1243

https://supportforums.cisco.com/videos/1197

jecheand · ‎03-09-2011

Hi lucien,

i had received my two first Nexus 5000 but one of them arrived without an NX-OS image and in Loader> prompt.

I tried to load by TFTP the kickstart image but the system gave me the following error message:

loader> boot tftp://172.16.1.3/n5000-uk9-kickstart.4.2.1.N2.1a.bin

Address: 172.16.1.2

Netmask: 255.255.255.0

Server: 172.16.1.3

Gateway: 172.16.1.1

Booting: /n5000-uk9-kickstart.4.2.1.N2.1a.bin console=ttyS0,9600n8nn quiet load

er_ver="pr-1.3"....ALERT: got a fragmented packet - reconfigure your server

ALERT: got a fragmented packet - reconfigure your server

TFTP error 0 (Unknown request code.)

Error 15: File not found

I tried this process with 2 different TFTP software 3cDaemon and Solarwinds but the problem persists.

Do you have any advice on these.

Thanks,

Pepe

Lucien Avramov · ‎03-09-2011

Do you mind trying with tftpd32:

http://tftpd32.jounin.net/tftpd32_download.html

jecheand · ‎03-10-2011

Hi Lucien, it works! but we have to enable the parameter PXE Compatibility in the Advanced TFTP Options to work.

Thank you very much.

Pepe