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STP-Switch can't communicate with each other

smartd1011
Level 1
Level 1

I added a STP lab (3 L3 switches)  into my exiting Route Redistribution network lab. I assigned trunk ports to appropriate  Gig. port to create trunk link between switches. I also issued command: spanning-tree vlan 10(20)  to each trunk port. I added a laptop to SW3 and assigned ip address(I don't have default gateway address, so used lo0 5.5.5.5 instead. I think I'm wrong ).

Now, I can't ping from one switch to another(except SW1 to SW2 through R1 and R2). I also can't ping from laptop to any switch or Vise Versa. I tried to debug for a couple of hr. but no luck. 

I attached the topology and config. file. 

I hope someone can help me find a clue.

 

Thank you!

18 Replies 18

As far as I know chaning the port form layer 2 to layer 3 and viceversa reset the config so the ip address shodul  have been cancelled

 

enrico

if I do this, will all the config will be lost?

Yes, if you configure an interf as layer 2 and then give a no switchport the previous config is lost. The same if you configure it as a layer 3 interf and then rollback to a layer2 port giving a switchport cmd.

I will leave it the way it is now, cause I don't want to loose any configs. Everything is working up to this point. 

 

Thank you so much for your help!

 

 

 

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