spanning tree

[mukeshjindal]

one stp topology is running if i will connect one more switch with it. Either it will affect our communication or not?

[jason]

Hi mukeshjindal,

The two key points that spring to mind is where is the root bridge?

If the switch you are adding is an edge / access device, make sure it has the default bridge priority of 32768.

As long as your root bridge has a lower priority (0 preferably) the rest of your network will not reconverge when you add the new switch.

[rosaho]

This discussion has been reposted from Cisco User Groups to the LAN, Switching and Routing community.

[Phillip Wilson]

mukeshjindal,

Jason is correct you want to manually set a root bridge so as to not have issues when adding new switches down the road. 

On another note you might want to also look into "spanning-tree rootguard" or "spanning-tree guard root".  This will disable ports (put them back into learning state) who would become the root bridge due to their BPDU advertisement. 

http://www.cisco.com/c/en/us/support/docs/lan-switching/spanning-tree-protocol/10588-74.html