Re: Nexus network Design - Switching LOOP

Martin, I beg to differ on this one. The document which you are referring to in figure 3 shows connectivity to a server.

@JD, It is not practical nor recommended to connect a access layer switch to a access layer switch, this is besides the point that the nexus 2k is designed not to have access layer switches connected by default hence the bpduguard is an automatic parameter. If you have no other ports on the 5k's, the only other option you have is to put yourself into a potential infinite loop scenario with the parallel setup you have..

How about this; if you have to use what you have. Of course you will have to turn off the bpduguard on the ex.. E1001/1/x ports connecting to the 3750.

  5k1------------5k2
      |. /
      |. /
      |. /
          2k
         ||
         ||
      3750
This gives you redundancy. Make sure you modify your load-balance protocol parameters on the 3750 to match those of the nexus.

Regards,
 Joe Sanchez

On Mar 13, 2012, at 8:48 AM, Martin Schumacher <martin1.schumacher_at_googlemail.com> wrote:

> this guide:
>
> https://www.cisco.com/en/US/docs/switches/datacenter/nexus5000/sw/layer2/513_n1_1/b_Cisco_n5k_layer2_config_gd_rel_513_N1_1_chapter_01001.html
>
> Your Topology should be Figure 3 -> single homed Fabric Extender VPC
> Topology
>
> Depending on the FEX Model you are using the number of possible port for
> the VPC can vary. (See the remark in the Config Guide)
>
> You create a Port-Channel on each Nexus 5000 with the commands you
> need...for example sw port type edge trunk, sw mode trunk
>
> But you will need a vpc to the switch...
>
> Greetings
>
> Martin
>
>
>
> 2012/3/13 jack daniels <jckdaniels12_at_gmail.com>
>
>> This configuration required on 2K ?
>> request your help in eleborating how this will solve the puzzle.
>>
>> On Tue, Mar 13, 2012 at 7:00 PM, Martin Schumacher
>> <martin1.schumacher_at_googlemail.com> wrote:
>>> channel-group 1 mode active (on each Fex one port for the Port-channel)
>>> switchport mode trunk
>>> switchport port type edge trunk
>>>
>>>
>>>
>>> 2012/3/13 jack daniels <jckdaniels12_at_gmail.com>
>>>>
>>>> Hi,
>>>>
>>>> but the ports will be transporting multple vlans.
>>>>
>>>> Regards
>>>>
>>>>
>>>> On Tue, Mar 13, 2012 at 6:47 PM, Radioactive Frog <pbhatkoti_at_gmail.com>
>>>> wrote:
>>>>> Totally agreed - no need of STP.
>>>>> VPC is thw way to go
>>>>> Have not touched Nexus for the last 9 months - is TRILL supported on
>> the
>>>>> latest codes yet?
>>>>> on edge where you have 2k connected to 3750 - put that port in edge
>>>>> mode.
>>>>>
>>>>>
>>>>> On Tue, Mar 13, 2012 at 11:55 PM, Carlos G Mendioroz <
>> tron_at_huapi.ba.ar>
>>>>> wrote:
>>>>>>
>>>>>> Yes, so what ?
>>>>>> As I said, STP is a bad word. You don't have to have STP in your
>>>>>> design!
>>>>>> -Carlos
>>>>>>
>>>>>> jack daniels @ 13/03/2012 09:49 -0300 dixit:
>>>>>>
>>>>>>> Hi Carlos,
>>>>>>>
>>>>>>> There is 2K in between which doesn't support STP.
>>>>>>>
>>>>>>> Regards
>>>>>>>
>>>>>>>
>>>>>>> On Tue, Mar 13, 2012 at 5:45 PM, Carlos G Mendioroz<
>> tron_at_huapi.ba.ar>
>>>>>>> wrote:
>>>>>>>>
>>>>>>>> STP is a bad word in Nexus :)
>>>>>>>> So you should take a look at VPC!
>>>>>>>>
>>>>>>>> Short story: make the two N5Ks behave as one entity to the 3750,
>>>>>>>> and make a LAG (etherchannel) between them.
>>>>>>>>
>>>>>>>> -Carlos
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>>
>> http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9670/configuration_guide_c07-543563.html
>>>>>>>>
>>>>>>>> jack daniels @ 13/03/2012 08:53 -0300 dixit:
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Hi Guys,
>>>>>>>>>
>>>>>>>>> I have a scenario for which I'm scratching my head since long -
>>>>>>>>> please
>>>>>>>>> help
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Nexus 5K-1---------Nexus5K-2
>>>>>>>>> | |
>>>>>>>>> | |
>>>>>>>>> Nexus2K-1 Nexus2K-2
>>>>>>>>> | | Port eth 1/1
>>>>>>>>> | |
>>>>>>>>> Cisco 3750-----------------------
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> In this scenario Switching LOOP is getting formed. Only way I'm
>> able
>>>>>>>>> to get rid is shutdown Port eth1/1 on Nexus2K-2. Please help in
>> this
>>>>>>>>> case.
>>>>>>>>>
>>>>>>>>> Thanks in anticipation in adavance.
>>>>>>>>>
>>>>>>>>> Regards
>>>>>>>>> Jack
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Blogs and organic groups at http://www.ccie.net
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>> _______________________________________________________________________
>>>>>>>>> Subscription information may be found at:
>>>>>>>>> http://www.groupstudy.com/list/CCIELab.html
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> Carlos G Mendioroz<tron_at_huapi.ba.ar> LW7 EQI Argentina
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>>>>>>
>>>>>>
>>>>>> Blogs and organic groups at http://www.ccie.net
>>>>>>
>>>>>>
>> _______________________________________________________________________
>>>>>> Subscription information may be found at:
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>>>>
>>>>
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>>>>
>>>> _______________________________________________________________________
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>
>
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Received on Tue Mar 13 2012 - 10:33:48 ART