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• on first VM launch/ last VM destroy on a host need setting up/destroy tunnel mesh for each tier's bridge with rest of the hosts. Latency to replicate configuration is proportional to  (n*(n-1))/2 * m where  n is the number of hosts on which VPC spans and m is the number of tiers in the VPC. n*(n-1)/2
• on VPC tier create/delete, needs setting up/destroy of bridge for the tier on all the hosts and setting up tunnel mesh. Latency is proportional to n * n-1/2 where n is number of hosts on which VPC spans + setting up the router entry on logical router
• on replace network ACL for a tier needs update of acl table on logical router on each host.

Performance and scaling issues

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