Re: Nexus network Design - Switching LOOP

Joe is on spot. Connecting 3750 to FEX goes against best practices and
SONA. Whoever mentioned this is an R & S forum is also correct. Interesting
conversation to a real world problem but out of scope for R & S lab.

I would re evaluate what you are trying to accomplish with the 3750 and
home it to distribution directly. I would also keep it removed from the
Data Center access/distribution as well.

HTH,

Marc

http://www.linkedin.com/in/santacruzbro

On Tue, Mar 13, 2012 at 8:33 AM, George J. Sanchez <marco207p_at_gmail.com>wrote:

> 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:
> >>>>>> http://www.groupstudy.com/list/CCIELab.html
> >>>>
> >>>>
> >>>> Blogs and organic groups at http://www.ccie.net
> >>>>
> >>>>
> _______________________________________________________________________
> >>>> Subscription information may be found at:
> >>>> http://www.groupstudy.com/list/CCIELab.html
> >
> >
> > Blogs and organic groups at http://www.ccie.net
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html

Blogs and organic groups at http://www.ccie.net
Received on Tue Mar 13 2012 - 11:47:18 ART