port priority

[robertkwild]

hi all,

got a cisco 3850 and one of the int is getting its uplink direct from the core switch and the other int is daisy chained to another edge switch which is going to another edge switch and then back to the core

i cant do a port channel as there not getting there uplinks direct from the core, so how can i make the int (directly attached to the core) the main one and this one wins all the time so to speak

thanks,

rob 

[MHM Cisco World]

Did you check below 

Spanning tree vlan x port-priorty 

Are this command allow ?

MHM

[robertkwild]

sorry i should had said both ports are trunked but one is directly uplinked to the core and the other link is going through other switches, so i want the one directly uplink to the core to win

[MHM Cisco World]

Yes I get' you want trunk to core to be elect as FWD abd other port as BLK.

Am I right ?

MHM

[robertkwild]

yes @MHM Cisco World i want the uplink directly plugged in the core to win and the other uplink (daisy chain switches) to be the standby one IF the other one fails

[MHM Cisco World]

Can I see 

Show spanning tree interface details (both interface)

Let check it before go further 

MHM

[robertkwild]

ok i see one int has priority 128.151 and the other int is 128.152

i got the above info from 

sh spanning-tree interface Te2/1/3 and then after Te2/1/4

i imagine the heavy weight wins ie 128.152

[Joseph W. Doherty]

Just to confirm, these links are all L2 and a STP variant is being used?

Is the core the STP root switch?

Are all the links same bandwidths?

Any manual interface STP costing?

If answers are yes, yes, yes and no, the least number of link hops back to the root should be the preferred path.

Otherwise, we'll need more information about the topology, as STP sees it.

[robertkwild]

ah great so the int directly connected to the core switch has the least number ie 128.151 so i should be good