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To STP or Not

I have a Cisco switch with 48 ports in it. To have multiple uplinks to the main/core switch, I want to create VLANs on the 48 port switch of 8 ports each, to give me 6 smaller broadcast domains. I will then connect these 8 ports to the core switch. Core switch has no VLANs nor I am planning any. My questions:

1. Should I enable STP or not.

2. Any better way of doing what I am doing above.

Thanks in advance.

Community Member

Re: To STP or Not

Your explanation is a little vague. I take it your comitting one VLAN of 8 ports to the connection to the Core switch ?

Assuming this, if these 8 ports are a VLAN and not a trunk how will your other 5 VLANs on the 48-port switch communicate to the core ?


Re: To STP or Not

Yes, I want to divide that 48 port switch into six, 8-port, switches and uplink each VLAN to core. So core will have 6 links from these VLANs or smaller switches. What does it mean, how other 5 VLANs communicate to the switch? Just like separate switches will. Does it all make sense?


Cisco Employee

Re: To STP or Not

Whatever is the size of your network or design of the network, it's never preferred that you disable the STP in your network. You never know when the loop will be created and your whole network go down. So it's highly recommended to enable STP in your network.

Also it's never recommended to elect the STP root based on default STP parameters. Manually let the core switch of the network to elect as a root switch. To get more guidelines, refer to the designing STP for trouble avoidance section of the following document:

Hope this helps

Community Member

Re: To STP or Not

Why not enable 6 uplinks from access layer switch to core switch (one per VL:AN) then you will have no need for Spanning tree as there will be no loop.

You would only need STP if you trunked more than one VLAN over any single uplink


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