1. What are the differences among Spot instance, On-Demand instance, and Reserved Instances?
All these instances are models for pricing. Spot instance powers the customers to acquire compute capacity without having any upfront commitment. The hourly rate of Spot instance is usually higher than the speed of the On-Demand instance. Both in Spot instance and On-Demand instance, the users, do not commit to any particular duration. However, there is a fixed period to which the users have to stick in the Reserved Instance.
2. What are the network performance parameters that you should be expecting when you launch Instances in a cluster placement group?
The network performance depends on two elements:-
- Instance type
- Network performance specification
One should expect the following things when instances are launched in a cluster placement group:
- 10 Gbps in a single flow
- 20 Gbps in full duplex
- Outside of the placement unit, the network traffic will be limited to 5 Gbps.
3. Is it enough to have only one Elastic IP for all the instances that I have been running?
There is no definite answer to this question because it depends on the instance. The instances have their public and private addresses. Both the private and the public address remains associated with the Amazon EC2 and instance respectively until it is terminated or stopped. These addresses can be replaced with Elastic address, and it remains with the Instance until the user does not manually detach it. If multiple websites are being hosted on EC2 server, more than one Elastic IP will be required.
4. What are the best practices for Security in Amazon EC2?
Following are the best practices for security in Amazon EC2:
- Usage of Access Management and AWS Identity to control the access given to the AWS resources.
- Allow only trusted host to access the ports of your instance by restricting access.
- A regular review of the security groups should be done.
5. How can the data transfer speed up in Snowball?
One can increase the rate of data transfer in Snowballs by executing the following ways:
- Do multiple copy operations at a single time
- Copy things from multiple workstations to the same snowball
- Transferring of large files should be done by creating small groups of the small file to reduce the encryption overhead
- Elimination of unnecessary hops
6. Why do you make subnets?
Subnets are created to utilize the networks efficiently that have a significant number of hosts. Managing a network, which is filled with a large number of hosts is very tedious. When the network is divided into subnets, it becomes easier to manage the hosts.
7. What are the differences among DynamoDB, Amazon RDS, and Redshift?
DynamoDB is a NoSQL database, which deals with unstructured data. Amazon RDS is meant to serve the relational databases. It manages the following things:
- Backing up of data
It does the tasks for you with any need of your intervention. It is meant to deal with the structured data only. Redshift, on the other hand, is not a database. It is a data warehouse product, which is used for data analysis.
8. What is the difference between Elasticity and Scalability?
Scalability refers to the ability of the system to increase and improve its hardware resources so that it can meet the growth in demand. Scalability can be achieved by increasing:
1. Hardware specifications
2. Processing nodes
Elasticity refers to the ability of the system to manage the growth in workload by increasing the hardware resources when the demands are high. However, when the demand is low, the additional hardware resources have to be rolled back. Elasticity becomes helpful when one is dealing with Cloud environments.
9. I want to transfer my present domain name registration to the Amazon Route 53 without disturbing or disrupting my current web traffic. What should I do to achieve this?
Follow the steps given below to transfer your domain name registration to Amazon route 53:
Step 1: Get a list of the DNS record data, which is available for your domain name.
Step 2: Use Route 53 Management Console to create a hosted zone, which will be storing the DNS records of your domain and then start the transfer process.
Step 3: Contact with the registrar with whom you have registered the domain name. Follow the transfer process.
Your DNS queries will be answered when the registrar propagates the requirement of the new name server delegations.
10. What automation tools will you spin up servers?
The following tools can be used to spin up servers:
1. Roll-your-own scripts tool
2. AWS API tools
3. Configuration management and provisioning tool (Example, Opscode Chef)
4. Managed solution tool (Example, Rightscale)