Re: Spanning tree .. Killing me .. :-(

Anthony,

Small doubt. :-) , Mainly port fast is used for end host system rite ? are
we using portfast for between switches tooo ?? How this will imapact in
between switches. in this case do we need to disable bpdu guard tooo ???

Anthony Sequeira <asequeira_at_ine.com>
Sent by: nobody_at_groupstudy.com
12/10/2009 10:47 AM
Please respond to
Anthony Sequeira <asequeira_at_ine.com>

To
Mohan Kumar Devarajan/Chennai/iNautix_at_iNautix
cc
Radioactive Frog <pbhatkoti_at_gmail.com>, Cisco certification
<ccielab_at_groupstudy.com>, nobody_at_groupstudy.com
Subject
Re: Spanning tree .. Killing me .. :-(

Hi Mohan!

The line <spanning tree enabled protocol ieee> on a 3560 indicated you
are running Per VLAN STP (802.1D or classic STP). What deceives
students is the fact that the interface output will still show
properties of RSTP, even though the switch is not implementing that
technology. This is kind of like how the show interface trunk output
will show the Native VLAN for an ISL trunk when we know there is no
such thing. :-)

In order to run RSTP on the device, you have two options. You can go
with Per VLAN RSTP, or you can go with MSTP, which will give you RSTP
automatically.

In order to engage in the fast convergence, all inter-switch links
must be full-duplex, point-to-point connections. For ports that
connect to hosts, we have Edge Ports. The PortFast command is still
recommended and used for the configuration of these ports.

Warmest Regards,

Anthony J. Sequeira, CCIE #15626
Senior CCIE Instructor
http://www.INE.com

Test your Core Knowledge today!
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A: Cisco Express Forwarding
More Info:
http://www.cisco.com/en/US/products/hw/routers/ps167/products_tech_note09186a00801e1dc2.shtml

On Dec 10, 2009, at 8:56 AM, MDevarajan_at_inautix.co.in wrote:

> Can someone please help me to understand the below concept..
>
>
> As per the below output .. I am thinking its running RSTP protocol
> rite
> ????
>
> Question 1 : if link type EDGE means .. its connected to enf HOST ..
> Am I
> rite ??
> Question 2: if link type is P2P means.. Its connected to other
> switch...
> Am I rite ???
>
>
> VLAN0005
> Spanning tree enabled protocol ieee
> Root ID Priority 8192
> Address 00d0.0152.1805
> Cost 3
> Port 1665 (Port-channel1)
> Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
>
> Bridge ID Priority 32768
> Address 00d0.015c.9c05
> Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec
> Aging Time 300
>
> Interface Role Sts Cost Prio.Nbr Type
> ---------------- ---- --- --------- --------
> --------------------------------
> Fa2/44 Desg FWD 19 128.172 Edge P2p
> Po1 Root FWD 3 128.1665 P2p
> Po2 Desg FWD 3 128.1666 P2p
>
>
> See the running config
>
> Hxxxxxxxx#sh run | inc span
> spanning-tree mode pvst
>
>
>
> Please advise me .. if router is running PVST .. Why the hell its
> showing
> as " Spanning tree enabled protocol ieee "
>
>
> Thanks,
> Mohan
>
>
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Received on Fri Dec 11 2009 - 03:50:46 ART