RE: Trunk Modes theory

From: Geert Nijs (geert.nijs@simac.be)
Date: Mon Mar 13 2006 - 13:42:26 GMT-3


Thanks. Good reference.

________________________________

From: Alex Arseniev [mailto:alex.arseniev@gmail.com]
Sent: maandag 13 maart 2006 16:57
To: Geert Nijs
Cc: ccielab@groupstudy.com
Subject: Re: Trunk Modes theory

I believe the answer is "no trunk is formed"
Reference
http://www.cisco.com/en/US/products/hw/switches/ps700/products_tech_note
09186a00801429fb.shtml
scroll down 1/2 page below and You see a table with possible
combinations and results.
Of course, this is valid for 5000/6000 switches, YMMV.
HTH
Cheers
Alex

On 13/03/06, Geert Nijs <geert.nijs@simac.be> wrote:

        All,

        I am studying for my recertification and although i do
understand the
        different trunking modes, there has been a large discussion
between me
        and
        a colleague for the following specific situation:

        First Situation
        SW1 - Fa0/1
           switchport mode trunk
           switchport trunk mode isl
           switchport trunk nonegotiate

        SW2 - Fa0/1
           swichport mode desirable

        Is an ISL trunk being formed or NOT ?
        Trick: nonegotiate makes the port NOT send any DTP packets.
        I always thought that "desirable" NEEDED DTP packets from the
other side
        to form a trunk (so: ON, AUTO or DESIRABLE)
        So i would say: NO, their is no trunk.

        Several books and docs seem to suggest that in this case, a
trunk will
        be formed. I am unable to test right now.
        So what will happen ?

        regards,

        Geert Nijs
        Service Engineer
        CCIE #13729
<http://www.cisco.com/en/US/learning/le3/ccie/index.html>

########################################################################
#####
        ########
        Simac N.V. trades under the commercial name Simac ICT Belgium.
        This e-mail and any attached files are confidential and may be
legally
        privileged.
        If you are not the addressee, any disclosure, reproduction,
copying,
        distribution,
        or other dissemination or use of this communication is strictly
prohibited.
        If you have received this transmission in error please notify
Simac
        immediately
        and then delete this e-mail.

        Simac has taken all reasonable precautions to avoid virusses in
this email.
        Simac does not accept liability for damage by virusses, for the
correct and
        complete
        transmission of the information, nor for any delay or
interruption of the
        transmission,
        nor for damages arising from the use of or reliance on the
information.

        All e-mail messages addressed to, received or sent by Simac or
Simac employees
        are deemed to be professional in nature. Accordingly, the sender
or recipient
        of
        these messages agrees that they may be read by other Simac
employees than the
        official
        recipient or sender in order to ensure the continuity of
work-related
        activities
        and allow supervision thereof.

########################################################################
#####
        ########



This archive was generated by hypermail 2.1.4 : Sat Apr 01 2006 - 10:07:38 GMT-3