Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Spanning tree issue

Hi,

I have configured core sw as root bridge for VLAN 64 (4096).

Core sw config:

spanning-tree vlan 64 priority 4096

I have checked the root bridge for VLAN 64 from access switch

ACC-SW1#sh spanning-tree vlan 64

VLAN0064

Spanning tree enabled protocol rstp

Root ID Priority 4160

Address 0012.00d0.1100

Cost 3

Port 56 (Port-channel1)

Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Bridge ID Priority 32832 (priority 32768 sys-id-ext 64)

Address 0023.ab2a.c280

Hello Time 2 sec Max Age 20 sec Forward Delay 15 sec

Aging Time 300

Interface Role Sts Cost Prio.Nbr Type

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

Po1 Root FWD 3 128.56 P2p

My question is why it is showing rott bridge as 4160..it suppose to show 4096 right??

Regards

sateesh

4 REPLIES

Re: Spanning tree issue

Hi,

The priority is Priority 4096 + Vlan ID=4096 + 64.

That is the extended system id.

If you want disable it, you must issue the command:

no spanning-tree extend system-id

I hope this helps.

Best regards.

Massimiliano.

New Member

Re: Spanning tree issue

Hi,

Thanks for prompt response. I have tried in the same way..But still its showing like that only..

Regards

sateesh

Re: Spanning tree issue

Hi,

You have to issue this command on root bridge.

Best regards.

Massimiliano.

New Member

Re: Spanning tree issue

HI,

I have issued the command on root bridge only and rebooted also

Still its like that..

Regards

sateesh

133
Views
0
Helpful
4
Replies