root guard

[ITtech101]

Hi,

I'm trying to work out where loop gurd should be enabled,
I have 4503 supII connected to 2 2950G, via 2 gigabit ports.
Should root guard be enabled on the ports on the supII module or on the 2950 gigabit ports.

cisco4503supII
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2950 2950

thanks for any help

 

[KiscoKid]

Root guard is usually configured on any port where the root bridge should not appear. it ensures the port in question is always a designated port and never a root port.

I presume in your example that the 4503 is your root? If so, the ports connected to both 2950's will be root ports. Therefore you do NOT enable root guard on these ports.

If, at a layer, below the 2950's you have another subset of switches, you could enable root guard on those ports that connect to these switches to stop those switches from ever becoming root.

 

[KiscoKid]

Sorry I made a small typo in the above. If the 4503 is your root, the ports connected to the 2950's are designated ports.

On the 2950's, the ports connected to the 4503 are root ports. But you do not enable root guard on the root port.