By default, how many Elastic IP addresses can you have per region for your EC2 instances?
D
The number of Elastic IP addresses you can have in EC2 per region is 5.
Reference:
http://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html#limits_ec2
Elasticity is one of the benefits of using Elastic Beanstalk. Which of the following best describes the concept of elasticity?
B
Because applications deployed using Elastic Beanstalk run on Amazon cloud resources, you should keep several things in mind when designing your application: scalability, security, persistent storage, fault tolerance, content delivery, software updates and patching, and connectivity. Elasticity is the streamlining of resource acquisition and release, so that your infrastructure can rapidly scale in and scale out as demand fluctuates.
Reference:
http://docs.aws.amazon.com/elasticbeanstalk/latest/dg/concepts.concepts.design.html
What is an Auto Scaling group?
B
An Auto Scaling group contains a collection of EC2 instances that share similar characteristics and are treated as a logical grouping for the purposes of instance scaling and management.
Reference:
http://docs.aws.amazon.com/autoscaling/latest/userguide/AutoScalingGroup.html
Which service is offered by Auto Scaling?
B
Auto Scaling is a service that allows users to scale the EC2 resources up or down automatically ac-cording to the conditions or by manual intervention. It is a seamless process to scale the EC2 compute units up and down.
Reference:
http://aws.amazon.com/autoscaling/
Which of the scaling options given below is not supported by Auto Scaling?
A
Auto Scaling supports three types of scaling:
Manual scaling -
Scaling based on condition (e.g. CPU utilization is up or down, etc.) Scaling based on time (e.g. First day of the quarter, 6 am every day, etc.).
Reference:
http://docs.aws.amazon.com/AutoScaling/latest/DeveloperGuide/scaling_plan.html
Security groups in Amazon VPC ______.
B
Security Groups in VPC allow you to specify rules for both outgoing and incoming traffic.
Reference:
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_SecurityGroups.html
______ in VPC are stateful where return traffic is automatically allowed, regardless of any rules.
A
Security groups in VPC are stateful where return traffic is automatically allowed without having to go through the whole evaluation process again. Network ACLs are stateless, meaning return traffic must be explicitly allowed by rules.
Reference:
http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Security.html
What happens if the instance launched by Auto Scaling becomes unhealthy?
A
Auto Scaling keeps checking the health of the EC2 instances launched by it at regular intervals. If an instance is observed as unhealthy, Auto Scaling will automatically terminate the instance and launch a new healthy instance. Thus, it maintains the number of instances as per the Auto Scaling group configuration.
Reference:
http://docs.aws.amazon.com/AutoScaling/latest/DeveloperGuide/AutoScalingLifecycleHooks.html
A user has set the Alarm for the CPU utilization > 50%. Due to an internal process, the current CPU utilization will be 80% for 6 hours. How can the user ensure that the CloudWatch alarm does not perform any action?
A
The user can disable or enable the CloudWatch alarm using the DisableAlarmActions and Ena-bleAlarmActions APIs or the mon-disable-alarm-actions and mon- enable-alarm-actions commands.
Reference:
http://docs.aws.amazon.com/AmazonCloudWatch/latest/DeveloperGuide/AlarmThatSendsEmail.html
A user is sending a custom metric to CloudWatch. If the call to the CloudWatch APIs has different dimensions, but the same metric name, how will CloudWatch treat all the requests?
A
A dimension is a key-value pair used to uniquely identify a metric. CloudWatch treats each unique combination of dimensions as a separate metric. Thus, if the user is making 4 calls with the same metric name but a separate dimension, it will create 4 separate metrics.
Reference:
http://docs.aws.amazon.com/AmazonCloudWatch/latest/DeveloperGuide/cloudwatch_concepts.html
