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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

Failure to set up a full tunnel mesh for a tier shall result in VM deployment failure.

Architecture & Design description

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ovstunnel: disable_logical_router

Failure mode

Failure to set up a full tunnel mesh for a tier shall result in VM deployment failure.

troubleshooting

To aid trouble shoot in case of connectivity or network acl functionality issues when VPC is enabled with distributed router, an admin API shall be introduced in OVS plugin that shall expose below details maintained by OVS topology guru and OVS tunnel manager

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