[c-nsp] [ASAP] STP port-cost

[Jonathan Crawford]

The port-channel config should be the one used. If you do a show
spanning-tree, you should notice that your port-channels will show up, but
the member interfaces will not. Other vendors show the member interfaces as
stp disabled due to being a port channel member, cisco just does not show
the interface.

In fact if you do a "show spanning-tree interface fe0/1" it should show the
port identifier as being the same as the port identifier of the portchannel.


!
interface GigabitEthernet1/11
 spanning-tree cost 100
 channel-protocol lacp
 channel-group 12 mode active
end

interface Port-channel12
 spanning-tree cost 10000
end

rtr1#show spanning-tree interface po12

Mst Instance     Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- --------
--------------------------------
MST0             Desg FWD 10000     128.1676 P2p
 
rtr1#show spanning-tree interface gi1/11

Mst Instance     Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- --------
--------------------------------
MST0             Desg FWD 10000     128.1676 P2p


-----Original Message-----
From: cisco-nsp-bounces at puck.nether.net
[mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of Hiromasa Sekiguchi
Sent: Monday, February 11, 2008 8:51 PM
To: cisco-nsp at puck.nether.net
Subject: [c-nsp] [ASAP] STP port-cost

Hi,

If I configure stp cost both FEC and physical ports on cat65k, which command
takes affect to stp calculation?

---
interface Port-channel1
 spanning-tree vlan 1 cost 100
 spanning-tree cost 100

interface FastEthernet0/1
 spanning-tree vlan 1 cost 100
 spanning-tree cost 100
 channel-group 1 mode on

interface FastEthernet0/2
 spanning-tree vlan 1 cost 100
 spanning-tree cost 100
 channel-group 1 mode on
---

I understand we will configure stp cost on FEC only, however we'd like to
know what behavior will be done.

I understand "spanning-tree vlan [vlan id] cost [cost]" command takes affect
as compared with "spanning-tree cost [cost]" command.

So, is there any documentation on cisco?
I couldn't find about it...

Regards,
Hiromasa