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If the flow rule in the bridge that sends inter tier traffic to go through the patch port to logical router is removed, then traffic will be sent to VPC VR for routing. This fact shall be used to build notion of enable/disable logical router. When a logical router is enabled, flow rule will set on each bridge corresponding to each tier in the VPC to direct inter-tier traffic to logical router. When a logical router is disabled, flow rule set on each bridge corresponding to each tier in the VPC to direct inter-tier traffic to logical router will be removed. 

Failure mode

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• Failure to set up a full tunnel mesh for VM in a tier shall result in VM deployment failure.
• Failure to setup one or more bridge of the VPC, in full-connected mesh topology shall result in logical router to be disabled

Architecture & Design description

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