- Amazon ELB automatically distributes incoming application traffic across multiple Amazon EC2 instances in Multiple Availability Zones. Amazon EC2 regions have different levels of AZ's, US-East EC2 region has 5 AZ's and Singapore has 2 AZ's. When you are migrating the ELB make sure your configuration matches the levels of target Amazon EC2 region Availability zones .
- When Amazon ELB is created on target Amazon EC2 region, the ELB endpoint will be different from the source one. This has to be re configured on your Route 53 and other thick clients during migration.
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