cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
714
Views
0
Helpful
9
Replies

Command help...

mahmoodmkl
Level 7
Level 7

Hi

From the output below

Port 65 (GigabitEthernet2/1) of VLAN0011 is forwarding

Port path cost 4, Port priority 128, Port Identifier 128.65.

Designated root has priority 24587, address 000f.3412.e7c0

Designated bridge has priority 24587, address 000f.3412.e7c0

Designated port id is 128.65, designated path cost 0

Timers: message age 0, forward delay 0, hold 0

Number of transitions to forwarding state: 1

Link type is point-to-point by default

BPDU: sent 474668, received 3

i want to know what does port 65 stands for.

Thanks

Mahmood

9 Replies 9

royalblues
Level 10
Level 10

Hi Mahmood,

I think its basically the priority number assigned by spanning tree.

When you do a sh spanning tree interface g 2/1, it will show you as a Prio.Nbr

MS_L3_M5#sh spanning-tree interface G2/1

Vlan Role Sts Cost Prio.Nbr Type

---------------- ---- --- --------- -------- --------------------------------

VLAN0011 Desg FWD 4 128.65 Shr

could not find any documentation though on cisco

HTH, rate if it does

Narayan

m.sir
Level 7
Level 7

I think gi 2/1 is root port (port through which the root bridge can be reached) and 65 is root path cost

M.

Hope that helps rate if it does

Its not the path cost.

The output shows

Port path cost 4, Port priority 128, Port Identifier 128.65.

Designated port id is 128.65

So the port priority is 128 and 65 is appended to it to make it ID.

Not sure how 65 is calculated maybe from ifindex

HTH, rate if it does

Narayan

Hi guys,

i agree with u.I too was not able to find any docs related to it.

Thanks

Mahmood

Hi,

Its not the Path Cost but the Gig 2/1 is the 65th Port of the switch.

If you check the same for Gig 2/2 it will show as Port 66.

Hope this will clear your doute.

Regards

Danny

Hi

No danny i dnot think so becoz u can see that its gig2/1.any updates...

Ankur where r u dear.

Thanks

Mahmood

Hi Mahmood,

Can you please give the same command for Gig 2/2 and give the output

Regards

Danny

Hi Mahmood,

Danny is right. The port g 2/2 will indeed show you 66 but it is not the 66th port of the switch but a number that is appended to the Priority of a port.

Still unable to find any docs related to it

Narayan

Hi Mohamood,

65 is Port and Gig 2/1 is a Interface.

Lets take 3550 Switch for example, it has Total 26 Ports of which It will can be said as 24 Eht Interface and 2 Gig Interface.

Hope your Doute is clear Rate me if so.

Regards

Danny

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Innovations in Cisco Full Stack Observability - A new webinar from Cisco