A Company Wants to Use a Grid System for a Proprietary

question 324

Multiple Choice

A company wants to use a grid system for a proprietary enterprise in-memory data store on top of AWS. This system can run in multiple server nodes in any Linux-based distribution. The system must be able to reconfigure the entire cluster every time a node is added or removed. When adding or removing nodes, an /etc./cluster/nodes.config file must be updated, listing the IP addresses of the current node members of that cluster The company wants to automate the task of adding new nodes to a cluster. What can a DevOps Engineer do to meet these requirements?

• A) Use AWS OpsWorks Stacks to layer the server nodes of that cluster. Create a Chef recipe that populates the content of the /etc/cluster/nodes.config file and restarts the service by using the current members of the layer. Assign that recipe to the Configure lifecycle event.
• B) Put the file nodes.config in version control. Create an AWS CodeDeploy deployment configuration and deployment group based on an Amazon EC2 tag value for the cluster nodes. When adding a new node to the cluster, update the file with all tagged instances, and make a commit in version control. Deploy the new file and restart the services.
• C) Create an Amazon S3 bucket and upload a version of the etc/cluster/nodes.config file. Create a crontab script that will poll for that S3 file and download it frequently. Use a process manager, such as Monit or systemd, to restart the cluster services when it detects that the new file was modified. When adding a node to the cluster, edit the file's most recent members. Upload the new file to the S3 bucket.
• D) Create a user data script that lists all members of the current security group of the cluster and automatically updates the /etc/cluster/nodes.config file whenever a new instance is added to the cluster

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Definitions:

Equation of Exchange

A monetary theory equation that states the money supply multiplied by the velocity of money equals the price level times the quantity of goods and services sold (MV = PQ).

Interest Rate

The part of a loan that incurs interest fees for the borrower, customarily indicated as an annual percentage of the unpaid loan.

Discretionary Policies

Economic strategies, involving government spending and taxation, that are implemented at the discretion of the government to manage economic fluctuations.

Monetarist Economists

Economists who believe that variations in the money supply have major influences on national output in the short run and the price level over longer periods.