STP protocol setup when installing switch between existing Nexus switc

[nehhetbderrt]

Hello, what is the best way to set up the STP protocol when installing a new Nexus 9000 switch between existing Nexus 3000 switches without changing the configuration on the existing switches, using the STP priority and STP root secondary commands?

[MHM Cisco World]

the Nexus run by default PVST 
so add SW in between without config make all NSK SW start new root election 
so to answer you which SW you want to be Root ?

[balaji.bandi]

Check the exiting configuration of the switch running what STP Priority and root bridge.

configure new device with differnet priority so that new device do not become as root bridge for that VLAN.

you can use root gaurd or play with priority if you looking alternative bridge for root :

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/6-x/layer2/configuration/guide/b_Cisco_Nexus_9000_Series_NX-OS_Layer_2_Switching_Configuration_Guide/b_Cisco_Nexus_9000_Series_NX-OS_Layer_2_Switching_Configuration_Guide_chapter_...

OLDSW# sh run spanning-tree

spanning-tree vlan 1-10 priority 4096

NEWSW# sh run spanning-tree

spanning-tree vlan 1-10 priority 16384