AWS EC2 Flashcards
Describe the differences between Amazon EC2 Security Groups and Network ACLs
Security Groups control inbound and outbound traffic at the instance level and are stateful, meaning that return traffic is automatically allowed.
Network ACLs are stateless and operate at the subnet level, providing a finer level of control over traffic but requiring explicit rules for both directions.
What are the benefits of using Amazon EC2 Elastic Network Interfaces (ENIs)?
ENIs enable instances to communicate with other instances in the same VPC or across VPC peering connections. They can also be attached to instances in different Availability Zones to facilitate high availability and fault tolerance.
How does the behavior of root device volumes differ between Instance Store-backed Instances and Amazon EBS-backed Instances?
For Instance Store-backed Instances, any data on the instance store volumes is deleted when the instance is terminated or fails, and they do not support the EC2 Stop action. In contrast, for Amazon EBS-backed Instances, the instance can be stopped and later restarted without affecting data stored in the attached volumes.
Question: An academic research institution is deploying a high-performance computing (HPC) cluster on Amazon EC2 instances to conduct complex molecular dynamics simulations. They require ultra-low-latency communication between instances to exchange large volumes of data efficiently. Which EC2 networking feature is best suited to meet the stringent communication requirements of this HPC workload?
Answer Choices:
A) Amazon EC2 Enhanced Networking
B) Amazon EC2 Placement Groups
C) Amazon EC2 Auto Scaling
D) Elastic Fabric Adapter (EFA)
Correct Answer: D) Elastic Fabric Adapter (EFA)
A company deployed a high-performance computing (HPC) cluster that spans multiple EC2 instances across multiple Availability Zones and processes various wind simulation models. Currently, the Solutions Architect is experiencing a slowdown in their applications and upon further investigation, it was discovered that it was due to latency issues.
Which is the MOST suitable solution that the Solutions Architect should implement to provide low-latency network performance necessary for tightly-coupled node-to-node communication of the HPC cluster?
a) Set up a spread placement group across multiple Availability Zones in multiple AWS Regions.
b) Set up AWS Direct Connect connections across multiple Availability Zones for increased bandwidth throughput and more consistent network experience.
c) Use EC2 Dedicated Instances.
d) Set up a cluster placement group within a single Availability Zone in the same AWS Region.
d) Set up a cluster placement group within a single Availability Zone in the same AWS Region.
The solo founder at a tech startup has just created a brand new AWS account. The founder has provisioned an Amazon EC2 instance 1A which is running in AWS Region A. Later, he takes a snapshot of the instance 1A and then creates a new Amazon Machine Image (AMI) in Region A from this snapshot. This AMI is then copied into another Region B. The founder provisions an instance 1B in Region B using this new AMI in Region B.
At this point in time, what entities exist in Region B?
a) 1 Amazon EC2 instance and 1 AMI exist in Region B
b) 1 Amazon EC2 instance and 1 snapshot exist in Region B
c) 1 Amazon EC2 instance and 2 AMIs exist in Region B
d) 1 Amazon EC2 instance, 1 AMI and 1 snapshot exist in Region B
d) 1 Amazon EC2 instance, 1 AMI and 1 snapshot exist in Region B
An ivy-league university is assisting NASA to find potential landing sites for exploration vehicles of unmanned missions to our neighboring planets. The university uses High Performance Computing (HPC) driven application architecture to identify these landing sites.
Which of the following Amazon EC2 instance topologies should this application be deployed on?
1. The Amazon EC2 instances should be deployed in a partition placement group so that distributed workloads can be handled effectively
2. The Amazon EC2 instances should be deployed in a cluster placement group so that the underlying workload can benefit from low network latency and high network throughput
3. The Amazon EC2 instances should be deployed in a spread placement group so that there are no correlated failures
4. The Amazon EC2 instances should be deployed in an Auto Scaling group so that application meets high availability requirements
- The Amazon EC2 instances should be deployed in a cluster placement group so that the underlying workload can benefit from low network latency and high network throughput
The key thing to understand in this question is that HPC workloads need
The payroll department at a company initiates several computationally intensive workloads on Amazon EC2 instances at a designated hour on the last day of every month. The payroll department has noticed a trend of severe performance lag during this hour. The engineering team has figured out a solution by using Auto Scaling Group for these Amazon EC2 instances and making sure that 10 Amazon EC2 instances are available during this peak usage hour. For normal operations only 2 Amazon EC2 instances are enough to cater to the workload.
As a solutions architect, which of the following steps would you recommend to implement the solution?
- Configure your Auto Scaling group by creating a scheduled action that kicks-off at the designated hour on the last day of the month. Set the desired capacity of instances to 10. This causes the scale-out to happen before peak traffic kicks in at the designated hour.
- Configure your Auto Scaling group by creating a scheduled action that kicks-off at the designated hour on the last day of the month. Set the min count as well as the max count of instances to 10. This causes the scale-out to happen before peak traffic kicks in at the designated hour
- Configure your Auto Scaling group by creating a target tracking policy and setting the instance count to 10 at the designated hour. This causes the scale-out to happen before peak traffic kicks in at the designated hour
- Configure your Auto Scaling group by creating a simple tracking policy and setting the instance count to 10 at the designated hour. This causes the scale-out to happen before peak traffic kicks in at the designated hour
- Configure your Auto Scaling group by creating a scheduled action that kicks-off at the designated hour on the last day of the month. Set the desired capacity of instances to 10. This causes the scale-out to happen before peak traffic kicks in at the designated hour
Scheduled scaling allows you to set your own scaling schedule. For example, let’s say that every week the traffic to your web application starts to increase on Wednesday, remains high on Thursday, and starts to decrease on Friday. You can plan your scaling actions based on the predictable traffic patterns of your web application. Scaling actions are performed automatically as a function of time and date.
A company runs a data processing workflow that takes about 60 minutes to complete. The workflow can withstand disruptions and it can be started and stopped multiple times.
Which is the most cost-effective solution to build a solution for the workflow?
1. Use Amazon EC2 spot instances to run the workflow processes
2. Use AWS Lambda function to run the workflow processes
3. Use Amazon EC2 on-demand instances to run the workflow processes
4. Use Amazon EC2 reserved instances to run the workflow processes
- Use Amazon EC2 spot instances to run the workflow processes
A research group runs its flagship application on a fleet of Amazon EC2 instances for a specialized task that must deliver high random I/O performance. Each instance in the fleet would have access to a dataset that is replicated across the instances by the application itself. Because of the resilient application architecture, the specialized task would continue to be processed even if any instance goes down, as the underlying application would ensure the replacement instance has access to the required dataset.
Which of the following options is the MOST cost-optimal and resource-efficient solution to build this fleet of Amazon EC2 instances?
- Use Amazon Elastic Block Store (Amazon EBS) based EC2 instances
- Use Amazon EC2 instances with Amazon EFS mount points
- Use Amazon EC2 instances with access to Amazon S3 based storage
- Use Instance Store based Amazon EC2 instances
- Use Instance Store based Amazon EC2 instances
As Instance Store based volumes provide high random I/O performance at low cost (as the storage is part of the instance’s usage cost) and the resilient architecture can adjust for the loss of any instance, therefore you should use Instance Store based Amazon EC2 instances for this use-case.
A software engineering intern at an e-commerce company is documenting the process flow to provision Amazon EC2 instances via the Amazon EC2 API. These instances are to be used for an internal application that processes Human Resources payroll data. He wants to highlight those volume types that cannot be used as a boot volume.
Can you help the intern by identifying those storage volume types that CANNOT be used as boot volumes while creating the instances? (Select two)
1.Throughput Optimized Hard disk drive (st1)
2.General Purpose Solid State Drive (gp2)
3.Cold Hard disk drive (sc1)
4.Provisioned IOPS Solid state drive (io1)
5.Instance Store
- Throughput Optimized Hard disk drive (st1)
- Cold Hard disk drive (sc1)
Throughput Optimized HDD (st1) and Cold HDD (sc1) volume types CANNOT be used as a boot volume, so these two options are correct.
A company has a web application that runs 24*7 in the production environment. The development team at the company runs a clone of the same application in the dev environment for up to 8 hours every day. The company wants to build the MOST cost-optimal solution by deploying these applications using the best-fit pricing options for Amazon Elastic Compute Cloud (Amazon EC2) instances.
What would you recommend?
1. Use on-demand Amazon EC2 instances for the production application and spot instances for the dev application
2. Use Amazon EC2 reserved instance (RI) for the production application and spot block instances for the dev application
3. Use Amazon EC2 reserved instance (RI) for the production application and spot instances for the dev application
4. Use Amazon EC2 reserved instance (RI) for the production application and on-demand instances for the dev application
- Use Amazon EC2 reserved instance (RI) for the production application and on-demand instances for the dev application
For the given use case, you can use Amazon EC2 Reserved Instances for the production application as it is run 24*7. This way you can get a 72% discount if you avail a 3-year term. You can use on-demand instances for the dev application since it is only used for up to 8 hours per day. On-demand offers the flexibility to only pay for the Amazon EC2 instance when it is being used (0 to 8 hours for the given use case)
