A user is planning to host a Highly Available system on the AWS VPC. Which of the below
mentioned statements is helpful in this scenario?
A.
Create VPC subnets in two separate availability zones and launch instances in different subnets.
B.
Create VPC with only one public subnet and launch instances in different AZs using that subnet.
C.
Create two VPCs in two separate zones and setup failover with ELB such that if one VPC fails it
will divert traffic to another VPC.
D.
Create VPC with only one private subnet and launch instances in different AZs using that subnet.
Explanation:
A Virtual Private Cloud (VPC) is a virtual network dedicated to the user’s AWS account. It enables
the user to launch AWS resources into a virtual network that the user has defined. The VPC is
always specific to a region. The user can create a VPC which can span multiple Availability
Zones by adding one or more subnets in each Availability Zone. Each subnet must reside entirely
within one Availability Zone and cannot span across zones.
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Subnets.html#VPCSubnet
Correct Answer A.
Create VPC subnets in two separate availability zones and launch instances in different subnets.
B. Create VPC with only one public subnet and launch instances in different AZs using that subnet.
(incorrect because, subnet exist in one AZ only)
C. Create two VPCs in two separate zones and setup failover with ELB such that if one VPC fails it
will divert traffic to another VPC.
(incorrect because, ELB support one VPC only)
D. Create VPC with only one private subnet and launch instances in different AZs using that subnet.
(incorrect because, subnet exist in one AZ only)