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Community Member

Question on collapsing design

With layer 3 switches now running in the Tbps speed, 10Gb ports,  and supporting BGP.   Is it okay to collpase all layers including WAN into a pair of these switches for a small data center-wan/core/aggregation/access.  

The WAN would sit on its own VLAN and the outside interfaces of the firewalls would be on access ports on that  VLAN.  The inside ports of the firewalls would connect to an internal  VLAN.  Physically the internet fibers would connect directly into the switches.

Everything is still redundant and split across the switches with no signle point of failure.  There would be no access into the switches from the outside world aside from maybe ping.




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Re: Question on collapsing design


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If there are no "network issues", you often only need additional devices when you run of ports.

If you want to allow for some "network issues" limiting their impact, you can use additional devices for that purpose.

The two layer or three layer designs are good practices when you need to scale your network when you must use additional devices.

Community Member

Question on collapsing design

Thanks for the response Joseph.

I've actually seen this design in the past running just fine also with 4900 series switches doing WAN routing running BGP with a default route and also taking care of internal VLANS for servers. It made me do a double take when seeing the internet connections going directly into the same switches and thats most people's response. I was acutally responsible for doing some outside pen testing on the switches and they came up clean.


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