how many switches

billfaith · ‎06-05-2008

How many hops of switches can I have? I have a core switch, which branches out to a second swith. Can I have another coming off the second switch? Is there a limit?

Jon Marshall · ‎06-05-2008

Bill

No specific limit but the Cisco recommendation is to have a diameter of no more than 7. This means

SW1 -> SW2 -> SW3 -> SW4 -> SW5 -> SW6 -> SW7

It is mainly to do with STP calculations. So you will be fine adding another switch.

Jon

Rajat Chauhan · ‎06-05-2008

Hi Bill,

Actually, its the IEEE recommendation to have a diameter not more than 7.

From STP point, you can use the "diameter" keyword to specify the Layer 2 network diameter. Thus, the switch automatically picks an optimal hello time, forward delay time, and maximum age time for a network of that diameter. This can significantly reduce the spanning tree convergence time.