How to Automatically Configure a Secondary Network Interface on an Amazon EC2 Instance
Question
You have an EC2 Instance based out of the Amazon Linux AMI.
You have created a secondary Network Interface and attached it to the running instance.
What needs to be done to ensure that the new network interface is configured automatically?
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.Answer - D.
The AWS documentation mentions the following.
Launching an Amazon Linux or Windows Server instance with multiple network interfaces automatically configures interfaces, private IPv4 addresses, and route tables on the operating system of the instance.
For more information on the Elastic Network Interface please see the below link:
http://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/using-eni.htmlTo ensure that the new network interface is configured automatically, you need to perform the following steps:
Identify the interface: Check the instance ID and the ID of the new network interface to ensure that you have the correct ones.
Modify the configuration: Connect to the instance using SSH, and modify the configuration file for the networking service. This file is typically located at /etc/sysconfig/network-scripts/ifcfg-ethX, where X is the number of the interface (e.g., eth1, eth2, etc.). You will need to modify the file to include the new interface, as well as any required configuration options such as IP address, subnet mask, and gateway.
Restart the networking service: After modifying the configuration file, you will need to restart the networking service to ensure that the changes take effect. You can do this by running the following command:
sudo service network restart
- Verify the configuration: Once the networking service has been restarted, you should verify that the new interface is configured correctly. You can do this by running the ifconfig command and checking the output for the new interface.
In summary, option A is incorrect because simply adding the interface to the network interfaces location on the instance is not sufficient to ensure that it is configured automatically. Option B is also incorrect because using the AWS CLI is not necessary for this task. Option C is incorrect because Amazon Linux AMI instances do support secondary interfaces. The correct answer is D, but it is important to understand the steps required to ensure that the new interface is configured automatically.
