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Apr 18th, 2010
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Please find attached diagram. What is the best design to connect the 6 cabinet switches to the main aggregation switch if I have only 2 fiber uplinks. No more cables can be laid between the cabinet and data center. Two Cabinet switches are L3 and four are L2. How to maximize the availibility yet simplifying the design?.



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Jon Marshall Sun, 04/18/2010 - 01:26
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When you say 2 switches are L3 and 4 are L2 does this mean the L3 switches are responsible for routing the vlan(s) on the L2 switches in the cabinet ?


syedraheel Sun, 04/18/2010 - 03:01
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Well it could be an option. There are data and voice vlans in each floor/cabinet( there are 3 more cabinets with 3 switches each connecting to the distribution switch with 2 fiber uplinks). Then there are also servers connected to the main switch. The default gateway of the servers is the firewall(not shown here). Now if I make the top 2 cabinet switches responsible for the routing then I'll also have to make the Cabinet to Aggregation link L3 rite?

I am personally comfortable of making it L2 all with Firewall being the gateway for all devices, little confused how to go about it when making it L3 at the cabinet?

Reza Sharifi Sun, 04/18/2010 - 06:34
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Have the top 2 switches do the routing for you and then layer-3 links between the theses switches and the firewall.  The firewall should not be doing routing. Let the router/switches do the routing.  Keep the functions separate.




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