You are planning to create a fault-tolerant EC2 Instance by creating a secondary network interface and a backup EC2 Instance.
Which of the following is a requirement to ensure the switch over can be done successfully? (Select TWO)
Click on the arrows to vote for the correct answer
A. B. C. D.Answer - B and D.
This is given in the AWS documentation.
You can attach a network interface in one subnet to an instance in another subnet in the same VPC.
Options A and C are incorrect because we require fault-tolerant infrastructure that can only be achieved when the network interface and instance must be in the different Availability Zone.
For more information on Elastic Network Interfaces, please refer to the below URL.
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-eni.html https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/MultipleIP.htmlTo create a fault-tolerant EC2 Instance, you can use a secondary network interface and a backup EC2 Instance. This approach allows for the creation of a failover mechanism in case the primary EC2 Instance fails.
To ensure a successful switch over, there are two requirements that must be met:
The network interface must reside in the same Availability Zone as the primary EC2 Instance.
The backup EC2 Instance must reside in a different Availability Zone than the primary EC2 Instance.
Explanation:
A. The network interface must reside in the same Availability Zone - This is a correct statement. By having the network interface in the same Availability Zone, the backup EC2 Instance can take over in case the primary EC2 Instance fails. This is because network interfaces cannot be moved across Availability Zones.
B. The network interface must reside in a different Availability Zone - This is not a correct statement. If the network interface is in a different Availability Zone, it cannot be used as a failover mechanism for the primary EC2 Instance because the backup EC2 Instance cannot access it.
C. The instance must reside in the same Availability Zone - This statement is not relevant to the requirements for a successful switch over using a secondary network interface and a backup EC2 Instance.
D. The instance must reside in a different Availability Zone - This statement is partially correct. The backup EC2 Instance must reside in a different Availability Zone than the primary EC2 Instance. This is because if both EC2 Instances were in the same Availability Zone and the Availability Zone failed, both EC2 Instances would fail.
In summary, the correct requirements to ensure a successful switch over using a secondary network interface and a backup EC2 Instance are:
The network interface must reside in the same Availability Zone as the primary EC2 Instance.
The backup EC2 Instance must reside in a different Availability Zone than the primary EC2 Instance.