RSTP Assistance

[ITGURU]

Morning All,

Please see below a setup which i am trying to achieve

 

I've enabled RSTP on all 3 switches, and looking to setup redundant links between core 1 and core 2 and core 1 and core 3 (i'm not looking to link Core 2 to core 3)

 

At the moment i've got the 2 links working between Core 1 and Core fine, however when i connect the second link from core 1 to core 3 , all links on Core 3 get broadcast storm and one of the links it not blocking.

 

I'm still learning Spanning Tree, but wondered what i've missed, either i need to configure priorities or ports independently although the first core 1 to core 2 setup worked out the box.

 

Any help appreciated.

 

Thanks.

[Steve21]

Out of curiosity, any reason you aren't just going to use link agg between them? If you're not linking 2-3, there's really no benefit of using your method afaik

 

That way you'll have 2 active links (or a/p depending how you prefer)

 

- In terms of your actual question, can you post the setup of how you've set them?

 

Steve

[ITGURU]

Out of curiosity, any reason you aren't just going to use link agg between them? If you're not linking 2-3, there's really no benefit of using your method afaik

 

That way you'll have 2 active links (or a/p depending how you prefer)

 

- In terms of your actual question, can you post the setup of how you've set them?

 

Steve

 

Link aggregation won't work for Core 2 and Core 3 because on those chassis switches both ports have to be on the same slot (it has 8 x 2 port 10GB ports) so if the slot fails both links go down.

I can only use link aggregation on core 1 as its a stack of switches so can LAG between different switches,.

I would like to connect to 2 different ports on 2 different slots so i am protecting against a slot and SFP module failure.

Currently between switch 1 and 2 i have 2 different ports on 2 different slots connected and working fine.

I am just trying to get the dual link between core 1 and core 3 to work the same as 1 and 2.

[Steve21]

Ah makes sense if that's how your chassis supports it

 

Can you post the current setup of the non-working one? (Like config settings), or have you just enabled it and nothing else? #show spanning-tree or your vendor equiv

 

Steve

[ITGURU]

here it is from core 3... eth 2.1 is single uplink to core switch 1

 

ether 4.8 would be the second link from core 3 to core 1.

 

Thanks.

Ah makes sense if that's how your chassis supports it

 

Can you post the current setup of the non-working one? (Like config settings), or have you just enabled it and nothing else? #show spanning-tree or your vendor equiv

 

Steve

[FN-GM]

Do you have portfast configured on your uplinks?