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New Member

Will two pairs of L3 switch in HSRP creat a loop?

So, I have two pairs of L3 switch in separate HSRP configuration. Those two sets are connected by only two connections, Primary of each is connected to primary of the other only and the standby is connected to a standby of the other. The connection between the L3 switches carry only L2 traffic (access ports to be exact, carrying only one VLAN). Will this arrangement create a loop? I also want to know who the data will transfer from, lets say, a L2 switch connected to one side of the HSRP to another switch in another side of the HSRP? I really appreciate the help. Topology attached.

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Apologies for the delayed

Apologies for the delayed response. You don't have to worry about any loops forming in that regard either, because Spanning Tree works on layer 2 which is independent of layer 3 protocols.  Spanning tree will work at layer 2 to block a single redundant port (based on your topology) to prevent loops.  Traffic destined from/to your L3 VIPs will reach them loop-free based on the convergence of your final Spanning Tree topology.

 

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There would be no loop.

There would be no loop.  Spanning tree works in the background to prevent that.  HSRP packets travel between routers over layer 2 so as long as you don't place a broadcast domain in the path of the HSRP routers (of the same group, ie. HSRP 1 R1 -> HSRP 1 R2) you could place as many switches in the path as you need, and HSRP wouldn't break.

 

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New Member

I was concerned more about

I was concerned more about the loops between the L3 switches (see how there is a circle/square topology between the 4 L3 switches in HSRP) which are transferring L2 data via access port. Excuse me if I the problem wasn't worded better.

Apologies for the delayed

Apologies for the delayed response. You don't have to worry about any loops forming in that regard either, because Spanning Tree works on layer 2 which is independent of layer 3 protocols.  Spanning tree will work at layer 2 to block a single redundant port (based on your topology) to prevent loops.  Traffic destined from/to your L3 VIPs will reach them loop-free based on the convergence of your final Spanning Tree topology.

 

Please rate if helpful.

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