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Connect uplinks to new distribution as well as old

Hi friends,

There is a data center migration in place and one of our customer wants the access switches to be connected to the new distribution switch while also keeping the connection to old distribution switch active.

The user vlans on the old dist. switch are completely different from the vlans on the new distribution. But the customer is scared of configuring the new uplinks as trunks as they may introduce a loop in the network. He is saying that configuring the uplink ports as access ports for the respective floor user vlan is good enough. But i am recommending the port to be trunk with the allowed vlan be the user vlan + management vlan.

Is there anything really to be paranoid about the looping here? I dont believe so. The distributions are running rapid pvst but i dont know about the access.

Thanks a lot



Re: Connect uplinks to new distribution as well as old

Look at your network layout , is there any redundancy built in where there is an inherent loop ? If not if won't cause a problem . Also if spanning tree is set correctly it should take care of any loops by blocking one side of the loop.

Re: Connect uplinks to new distribution as well as old


You can take this opportunity to add VLAN load balancing at distribution & make primary & secondary root by adjusting priority of VLAN's at distribution switches.

But then you need to create old vlan's in new distribution switch & vice-versa.