RE: Disabling spanning tree

I do and it has been posted. Of course, you are welcome to put your own
answer on your own test.

Also, please everyone stop hitting reply all. Just respond to the group.

tv

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Clark, Neil (ACP)
Sent: Thursday, April 23, 2009 5:41 PM
To: Cisco Fanatic; eshedalonie_at_gmail.com; pbhatkoti_at_gmail.com
Cc: tparamba_at_thecontactcentre.ae; gwood83_at_gmail.com; ccielab_at_groupstudy.com;
nobody_at_groupstudy.com; tvarriale_at_flamboyaninc.com
Subject: RE: Disabling spanning tree

I know this thread has been going on for a while, but not sure how many
will agree but surely the key word is 'Disable' when you disable
something you stop it from working not erase it completely with this in
mind enabling BPDU filtering would be the obvious choice I think, as
this would stop the function of spanning tree on the port but not remove
spanning tree completely. However I also agree with a lot of others
that it would be heavily dependant on the context of the question and
what knock on effects this could have on past or future tasks. I fear
we shall never know the answer to this question!!

Cheers

Neil

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
Cisco Fanatic
Sent: 18 April 2009 15:48
To: eshedalonie_at_gmail.com; pbhatkoti_at_gmail.com
Cc: tparamba_at_thecontactcentre.ae; gwood83_at_gmail.com;
ccielab_at_groupstudy.com; nobody_at_groupstudy.com;
tvarriale_at_flamboyaninc.com
Subject: RE: Disabling spanning tree

Reading the fine lines of the Doc CD -

Enabling BPDU
filtering on an interface is the same as disabling spanning tree.

-Yuri

> Date: Sat, 18 Apr 2009 13:04:55 +0200
> Subject: Re: Disabling spanning tree
> From: eshedalonie_at_gmail.com
> To: pbhatkoti_at_gmail.com
> CC: tparamba_at_thecontactcentre.ae; gwood83_at_gmail.com;
> ccielab_at_groupstudy.com;
nobody_at_groupstudy.com; tvarriale_at_flamboyaninc.com
>
> Is this also can be a solution ?
>
> Configuring 802.1Q and Layer 2 Protocol Tunneling
>
>
>
http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/relea
se/12
.2_25_se/configuration/guide/swtunnel.html
>
> * When a port is configured as an 802.1Q tunnel port, spanning-tree
> bridge protocol data unit (BPDU) filtering is automatically enabled on

> the interface. Cisco Discovery Protocol (CDP) is automatically
> disabled on the interface
>
>
>
>
>
> On 4/17/09, Radioactive Frog <pbhatkoti_at_gmail.com> wrote:
> >
> > Exactly, we need to know other part of questions in this equation.
> > In
short
> > we can use either:
> >
> > a) no Switchport
> > b) bpdu filter.
> >
> > story ends up here...
> >
> > off to pound :)
> >
> >
> > On Fri, Apr 17, 2009 at 1:04 PM, Thameem Maranveetil Parambath <
> > tparamba_at_thecontactcentre.ae> wrote:
> >
> > > I dont think that "no switchport" is a solution here... If you
convert
> > > the interface to L3 , what IP will you provide to it?
> > >
> > > Regards
> > >
> > >
> > >
> > >
> > > Jonathan Greenwood II <gwood83_at_gmail.com> Sent by:
> > > nobody_at_groupstudy.com
> > > 17/04/2009 01:46 AM
> > > Please respond to
> > > Jonathan Greenwood II <gwood83_at_gmail.com>
> > >
> > >
> > > To
> > > Tony Varriale <tvarriale_at_flamboyaninc.com> cc ccielab
> > > <ccielab_at_groupstudy.com> Subject
> > > Re: Disabling spanning tree
> > >
> > >
> > >
> > >
> > >
> > >
> > > There's your answer. Thanks Tony for finding out the other
requirements.
> > > I
> > > was going against the grain as to the vague question and not
> > > knowing
all
> > > the
> > > requirements. I agree with you on bpdufilter, but the output of
> > > the sh spanning-tree tells a different story. When I get a chance

> > > I'm going to sniff a port with bpdufilter and see the operation.
> > > It wouldn't be
> > the
> > > first time the DocCd was wrong about how a command actually
works.
Case
> > > in
> > > point, Pavel did a good job on defunking the max-reserved
> > > bandwidth command with QoS & the DocCD. Hopefully that's not the
> > > case with this command.
> > >
> > > Cheers
> > >
> > > Jonathan Greenwood II
> > > CCIE #22744
> > >
> > > On Thu, Apr 16, 2009 at 1:46 PM, Tony Varriale
> > > <tvarriale_at_flamboyaninc.com>wrote:
> > >
> > > > Except 2 pages back in the lab book that mentions that this port
needs
> > > to
> > > > be
> > > > in vlan xy or z.
> > > >
> > > > The question gave a hint in that you cannot use "no
spanning-tree".
> > It's
> > > > all right there...all you have to do is see it.
> > > >
> > > > tv
> > > >
> > > > -----Original Message-----
> > > > From: Ryan West [mailto:rwest_at_zyedge.com]
> > > > Sent: Thursday, April 16, 2009 3:16 PM
> > > > To: Jonathan Greenwood II; Tony Varriale
> > > > Cc: ccielab
> > > > Subject: RE: Disabling spanning tree
> > > >
> > > > Johathan and the original person who mentioned "no switchport":
> > > >
> > > > Rack1SW3#show spanning-tree int f0/5
> > > >
> > > > Vlan Role Sts Cost Prio.Nbr Type
> > > > ------------------- ---- --- --------- --------
> > > > --------------------------------
> > > > VLAN0005 Desg FWD 19 128.5 P2p
> > > >
> > > > interface FastEthernet0/5
> > > > switchport access vlan 5
> > > > switchport mode dynamic desirable end Rack1SW3(config)#in f0/5
> > > > Rack1SW3(config-if)#no swi Rack1SW3(config-if)#end Rack1SW3#show

> > > > spa *Mar 1 01:53:25.083: %LINK-3-UPDOWN: Interface
> > > > FastEthernet0/5,
> > changed
> > > > state to up
> > > > Rack1SW3#show span
> > > > Rack1SW3#show spanning-tree int
> > > > *Mar 1 01:53:26.039: %SYS-5-CONFIG_I: Configured from console
> > > > by
> > > console
> > > > *Mar 1 01:53:26.083: %LINEPROTO-5-UPDOWN: Line protocol on
> > > > Interface FastEthernet0/5, changed state to up Rack1SW3#show
> > > > spanning-tree int f0/5 no spanning tree info available for
> > > > FastEthernet0/5
> > > >
> > > > winner winner chicken dinner?
> > > >
> > > > -ryan
> > > >
> > > > -----Original Message-----
> > > > From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On
> > > > Behalf
> > Of
> > > > Jonathan Greenwood II
> > > > Sent: Thursday, April 16, 2009 3:59 PM
> > > > To: Tony Varriale
> > > > Cc: ccielab
> > > > Subject: Re: Disabling spanning tree
> > > >
> > > > My answer would still be "no switchport" Bottom line BPDUfilter

> > > > is a
> > > STP
> > > > feature. Any command that involves "spanning-tree" on a
> > > > interface
> > > utilizes
> > > > STP, and by default STP runs on every port on a switch .
> > > > There's no command that can disable STP on a "per" interface
> > > > basis. There's nothing in
> > the
> > > > question that says you can't convert the port to layer 3. Now I
> > haven't
> > > > tested this but maybe someone could do a sho spanning-tree on a
> > > > layer
2
> > > > port
> > > > and try the same on a layer 3 port. If you don't see STP on the
layer
> > 3
> > > > port then its safe to say your not running it. I'm pretty sure
> > > > STP
> > will
> > > > come up on the layer 2 port. Just my thoughts.
> > > >
> > > > HTH
> > > >
> > > > Jonathan Greenwood II
> > > > CCIE #22744
> > > >
> > > > On Thu, Apr 16, 2009 at 12:07 PM, Tony Varriale
> > > > <tvarriale_at_flamboyaninc.com>wrote:
> > > >
> > > > > STP cannot be operational without BPDUs.
> > > > >
> > > > >
> > > > >
> > > > > BPDU filter effectively disables spanning tree on a port
> > > > > because it
> > > > filters
> > > > > in AND out. Is it a turn off knob? No. Is it a trick? Yes.
> > > > >
> > > > >
> > > > >
> > > > > tv
> > > > >
> > > > >
> > > > >
> > > > > From: Jonathan Greenwood II [mailto:gwood83_at_gmail.com]
> > > > > Sent: Thursday, April 16, 2009 1:48 PM
> > > > > To: Tony Varriale
> > > > > Cc: ccielab
> > > > > Subject: Re: Disabling spanning tree
> > > > >
> > > > >
> > > > >
> > > > > STP is still operational as the port still must transtion
> > > > > through
the
> > > > > various port states, in this case you have portfast which is a

> > > > > STP
> > > > feature.
> > > > > That's still STP wouldn't you agree regardless of BPDU's being
> > > filtered
> > > > or
> > > > > not? I don't have access to a switch at the moment, but I
> > > > > agree
with
> > > > your
> > > > > test. My argument is that you can't disable STP on a per port
basis.
> > > > >
> > > > > Jonathan Greenwood II
> > > > >
> > > > > CCIE #22744
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > On Thu, Apr 16, 2009 at 11:40 AM, Tony Varriale <
> > > > > tvarriale_at_flamboyaninc.com>
> > > > > wrote:
> > > > >
> > > > > The question mentions nothing about TCNs or port flapping.
> > > > >
> > > > > How about config BPDUs? Put it up in a lab...
> > > > >
> > > > > Here's a quick example in production for you that has portfast

> > > > > but
> > not
> > > > > bpdufilter:
> > > > >
> > > > > interface GigabitEthernet9/12
> > > > > switchport
> > > > > switchport access vlan 12
> > > > > switchport mode access
> > > > > spanning-tree portfast
> > > > >
> > > > > xyz#sh spanning-tree int g9/12 d
> > > > > BPDU: sent 10566749, received 0
> > > > >
> > > > > Spanning tree is not disabled. Period.
> > > > >
> > > > > Here's one in production with bpdufilter:
> > > > >
> > > > > xyz#sh run int g1/1
> > > > > Building configuration...
> > > > >
> > > > > Current configuration : 171 bytes !
> > > > > interface GigabitEthernet1/1
> > > > > switchport access vlan 201
> > > > > switchport mode access
> > > > > spanning-tree portfast
> > > > > spanning-tree bpdufilter enable
> > > > >
> > > > > xyz#sh spanning-tree int g1/1 d
> > > > > BPDU: sent 0, received 0
> > > > >
> > > > > No BPDUs sent or received. If both are none, would you say
> > > > > it's participating in spanning tree?
> > > > >
> > > > > tv
> > > > >
> > > > >
> > > > > -----Original Message-----
> > > > > From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On
Behalf
> > > Of
> > > > >
> > > > > Jonathan Greenwood II
> > > > > Sent: Thursday, April 16, 2009 1:25 PM
> > > > > To: Tharak Abraham
> > > > > Cc: Salah ElShekeil; ccielab
> > > > > Subject: Re: Disabling spanning tree
> > > > >
> > > > > With portfast TCN BPDU's will not be sent if a port goes up or

> > > > > down
> > > thats
> > > > > configured for portfast. FYI
> > > > >
> > > > > Jonathan Greenwood II
> > > > > CCIE #22744
> > > > >
> > > > > On Thu, Apr 16, 2009 at 11:17 AM, Tharak Abraham
> > > > > <tharakabraham_at_gmail.com>wrote:
> > > > >
> > > > > > Spanning tree would be still be active even if you enable
portfast
> > > and
> > > > > > bpdus will be sent out !
> > > > > >
> > > > > > bpdu filter on access ports will stop all kinds of bpdu's
> > > > > > and
hence
> > > > that
> > > > > > should be more appropriate in this context !
> > > > > >
> > > > > >
> > > > > > Tharak Abraham Luke
> > > > > >
> > > > > >
> > > > > > On Thu, Apr 16, 2009 at 8:04 PM, Jonathan Greenwood II <
> > > > > > gwood83_at_gmail.com> wrote:
> > > > > >
> > > > > >> I agree with Mr. West. They are looking for portfast
based on
> > > your
> > > > > >> question.
> > > > > >>
> > > > > >> HTH
> > > > > >>
> > > > > >> Jonathan Greenwood II
> > > > > >> CCIE #22744
> > > > > >>
> > > > > >> On Thu, Apr 16, 2009 at 10:17 AM, Salah ElShekeil <
> > > > > >> salah.elshekeil_at_gmail.com
> > > > > >> > wrote:
> > > > > >>
> > > > > >> > Dear all,
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> > how to disable spanning tree on an interface without
> > > > > >> > using "no
> > > > > spanning
> > > > > >> > tree" command?
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> > Salah
> > > > > >> >
> > > > > >> >
> > > > > >> > Blogs and organic groups at http://www.ccie.net <
> > > > http://www.ccie.net/
> > > > > >
> > > > > >> >
> > > > > >> >
> > > > >
> > > __________________________________________________________________
> > > _____
> > > > > >> > Subscription information may be found at:
> > > > > >> > http://www.groupstudy.com/list/CCIELab.html
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >> >
> > > > > >>
> > > > > >>
> > > > > >> --
> > > > > >> Jonathan Greenwood II
> > > > > >> CCIE #22744
> > > > > >>
> > > > > >>
> > > > > >> Blogs and organic groups at http://www.ccie.net <
> > > http://www.ccie.net/
> > > > >
> > > > > >>
> > > > > >>
> > > >
Received on Thu Apr 23 2009 - 19:59:01 ART