Hm. Then Cisco needs to update their documentation :-). I stand corrected.

I doubt they are random numbers.

What device was this on?

--
Marko Milivojevic - CCIE #18427
Senior Technical Instructor - IPexpert

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On Sun, Jun 27, 2010 at 11:14, Atle Ørn Hardarson
<[email protected]> wrote:
> Actually, Marko - I don't think so - I checked that very same port out:
> Switch#show snmp mib ifmib ifindex Po1
> Interface = Port-channel1, Ifindex = 218
> Switch#show spanning-tree interface po1 detail
>  Port 1665 (Port-channel1) of VLAN0001 is designated forwarding
> (...)
> It's SNMP ifindex is 218, but it's "STP ID" is 1665 - so to me it appears
> that it is some kind of separate identifier exclusive to STP...
> Btw, your audio lessons are great and very helpful, I listen to them every
> day as a part of the BLS.
> Atle
>
> On Wed, Jun 23, 2010 at 4:43 PM, Marko Milivojevic <[email protected]>
> wrote:
>>
>> Just one minor correction on Tyson's response. Port ID used by STP is
>> derived from SNMP ifindex for that port.
>>
>> --
>> Marko Milivojevic - CCIE #18427
>> Senior Technical Instructor - IPexpert
>>
>> YES! We include 400 hours of REAL rack
>> time with our Blended Learning Solution!
>>
>> Mailto: [email protected]
>> Telephone: +1.810.326.1444
>> Fax: +1.810.454.0130
>> Web: http://www.ipexpert.com/
>>
>> On Wed, Jun 23, 2010 at 14:39, Tyson Scott <[email protected]> wrote:
>> > 1 Yes
>> >
>> > 2 Yes
>> >
>> > 3 Total Accumulated Path Cost to the root Bridge
>> >
>> > 4. The number of times SPT has been recalculated on the Path
>> >
>> > 5. A port set to mode dynamic desirable will default to access mode if
>> > no
>> > device negotiates on the remote end yet it is still the recommendation
>> > to
>> > set the mode to access when you know it is connected to end devices.
>> >
>> >
>> >
>> > HTH
>> >
>> >
>> >
>> > Regards,
>> >
>> >
>> >
>> > Tyson Scott - CCIE #13513 R&S, Security, and SP
>> >
>> > Managing Partner / Sr. Instructor - IPexpert, Inc.
>> >
>> > Mailto: [email protected]
>> >
>> > Telephone: +1.810.326.1444, ext. 208
>> >
>> > Live Assistance, Please visit: www.ipexpert.com/chat
>> >
>> > eFax: +1.810.454.0130
>> >
>> >
>> >
>> > IPexpert is a premier provider of Self-Study Workbooks, Video on Demand,
>> > Audio Tools, Online Hardware Rental and Classroom Training for the Cisco
>> > CCIE (R&S, Voice, Security & Service Provider) certification(s) with
>> > training locations throughout the United States, Europe, South Asia and
>> > Australia. Be sure to visit our online communities at
>> > www.ipexpert.com/communities and our public website at www.ipexpert.com
>> >
>> >
>> >
>> > From: [email protected]
>> > [mailto:[email protected]] On Behalf Of Atle Ørn
>> > Hardarson
>> > Sent: Wednesday, June 23, 2010 5:21 AM
>> > To: [email protected]
>> > Subject: [OSL | CCIE_RS] show spanning-tree int xx detail
>> >
>> >
>> >
>> > Hi everyone
>> >
>> >
>> >
>> > Can someone please explain to me so that I understand the following
>> > output
>> > better:
>> >
>> >
>> >
>> > switch# show spanning-tree interface Po1 detail
>> >
>> >
>> >
>> >  Port 1665 (Port-channel1) of VLAN0001 is designated forwarding
>> >
>> >    Port path cost 3, Port priority 128, Port Identifier 128.1665.
>> >
>> >    Designated root has priority 24577, address 0009.12e9.aec0
>> >
>> >    Designated bridge has priority 32769, address 0014.f113.fc00
>> >
>> >    Designated port id is 128.1665, designated path cost 10
>> >
>> >    Timers: message age 0, forward delay 0, hold 0
>> >
>> >    Number of transitions to forwarding state: 16
>> >
>> >    Link type is point-to-point by default
>> >
>> >    BPDU: sent 9090982, received 2782
>> >
>> >
>> >
>> >
>> >
>> > Please find the breakdown of my questions below:
>> >
>> >
>> >
>> >  "Port 1665 (Port-channel1) of VLAN0001 is designated forwarding"
>> >
>> > *** Where does the switch get the value of "Port 1665" from? Is this an
>> > STP
>> > internal identifier of the port?
>> >
>> >
>> >
>> > "Port path cost 3, Port priority 128, Port Identifier 128.1665."
>> >
>> > *** The port path cost and port priority shown here are LOCAL values, am
>> > I
>> > correct in this assumption? There are no cumulative values represented
>> > here.
>> >
>> >
>> >
>> >  "Designated port id is 128.1665, designated path cost 10"
>> >
>> > *** The designated port ID is the REMOTE value sent from the neighboring
>> > switch, but *what* is the "designated path cost" and how is it
>> > calculated?
>> >
>> > *** Is the designated path cost the same as the "root path cost"?
>> >
>> >
>> >
>> > "Number of transitions to forwarding state: 16"
>> >
>> > *** What exactly does this mean? I used to think that this number
>> > represented the classic STP states, but a value of 16 has me confused.
>> > What
>> > states are they referring to here?
>> >
>> >
>> >
>> > "Link type is point-to-point by default"
>> >
>> > *** In Cisco's CCIE official study guide, it is recommended that a port
>> > channel is configured with the "spanning-tree link-type point-to-point"
>> > command, in order to facilitate a quick connection, but is it really
>> > necessary to hard-code this command on the interface, as it is obviously
>> > the
>> > default link-type on etherchannel? A bit confusing
>> >
>> >
>> >
>> > Thanks!
>> >
>> >
>> >
>> > Atle
>> >
>> > _______________________________________________
>> > For more information regarding industry leading CCIE Lab training,
>> > please
>> > visit www.ipexpert.com
>> >
>> >
>
>
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