Oracle Oracle Certifications 1Z0-1084-20 Questions & Answers

• Question 11:

  You have deployed a Python application on Oracle Cloud Infrastructure Container Engine for Kubernetes. However, during testing you found a bug that you rectified and created a new Docker image. You need to make sure that if this new Image doesn't work then you can roll back to the previous version. Using kubectl, which deployment strategies should you choose?

  A. Rolling Update

  B. Canary Deployment

  C. Blue/Green Deployment

  D. A/B Testing

  Correct Answer: C

  Canary deployments are a pattern for rolling out releases to a subset of users or servers. The idea is to first deploy the change to a small subset of servers, test it, and then roll the change out to the rest of the servers. The canary deployment serves as an early warning indicator with less impact on downtime: if the canary deployment fails, the rest of the servers aren't impacted. Blue-green deployment is a technique that reduces downtime and risk by running two identical production environments called Blue and Green. At any time, only one of the environments is live, with the live environment serving all production traffic. For this example, Blue is currently live and Green is idle. A/B testing is a way to compare two versions of a single variable, typically by testing a subject's response to variant A against variant B, and determining which of the two variants is more effective A rolling update offers a way to deploy the new version of your application gradually across your cluster.

• Question 12:

  Who is responsible for patching, upgrading and maintaining the worker nodes in Oracle Cloud Infrastructure Container Engine for Kubernetes (OKE)?

  A. It Is automated

  B. Independent Software Vendors

  C. Oracle Support

  D. The user

  Correct Answer: D

  After a new version of Kubernetes has been released and when Container Engine for Kubernetes supports the new version, you can use Container Engine for Kubernetes to upgrade master nodes running older versions of Kubernetes. Because Container Engine for Kubernetes distributes the Kubernetes Control Plane on multiple Oracle-managed master nodes (distributed across different availability domains in a region where supported) to ensure high availability, you're able to upgrade the Kubernetes version running on master nodes with zero downtime. Having upgraded master nodes to a new version of Kubernetes, you can subsequently create new node pools running the newer version. Alternatively, you can continue to create new node pools that will run older versions of Kubernetes (providing those older versions are compatible with the Kubernetes version running on the master nodes). Note that you upgrade master nodes by performing an `in-place' upgrade, but you upgrade worker nodes by performing an `out-of-place' upgrade. To upgrade the version of Kubernetes running on worker nodes in a node pool, you replace the original node pool with a new node pool that has new worker nodes running the appropriate Kubernetes version. Having 'drained' existing worker nodes in the original node pool to prevent new pods starting and to delete existing pods, you can then delete the original node pool.

• Question 13:

  Which two are benefits of distributed systems?

  A. Privacy

  B. Security

  C. Ease of testing

  D. Scalability

  E. Resiliency

  Correct Answer: DE

  distributed systems of native-cloud like functions that have a lot of benefit like Resiliency and availability Resiliency and availability refers to the ability of a system to continue operating, despite the failure or suboptimal performance of some of its components. In the case of Oracle Functions: The control plane is a set of components that manages function definitions. The data plane is a set of components that executes functions in response to invocation requests. For resiliency and high availability, both the control plane and data plane components are distributed across different availability domains and fault domains in a region. If one of the domains ceases to be available, the components in the remaining domains take over to ensure that function definition management and execution are not disrupted. When functions are invoked, they run in the subnets specified for the application to which the functions belong. For resiliency and high availability, best practice is to specify a regional subnet for an application (or alternatively, multiple AD- specific subnets in different availability domains). If an availability domain specified for an application ceases to be available, Oracle Functions runs functions in an alternative availability domain. Concurrency and Scalability Concurrency refers to the ability of a system to run multiple operations in parallel using shared resources. Scalability refers to the ability of the system to scale capacity (both up and down) to meet demand. In the case of Functions, when a function is invoked for the first time, the function's image is run as a container on an instance in a subnet associated with the application to which the function belongs. When the function is executing inside the container, the function can read from and write to other shared resources and services running in the same subnet (for example, Database as a Service). The function can also read from and write to other shared resources (for example, Object Storage), and other Oracle Cloud Services. If Oracle Functions receives multiple calls to a function that is currently executing inside a running container, Oracle Functions automatically and seamlessly scales horizontally to serve all the incoming requests. Oracle Functions starts multiple Docker containers, up to the limit specified for your tenancy. The default limit is 30 GB of RAM reserved for function execution per availability domain, although you can request an increase to this limit. Provided the limit is not exceeded, there is no difference in response time (latency) between functions executing on the different containers.

• Question 14:

  You created a pod called "nginx" and its state is set to Pending. Which command can you run to see the reason why the "nginx" pod is in the pending state?

  A. kubect2 logs pod nginx

  B. kubect2 describe pod nginx

  C. kubect2 get pod nginx

  D. Through the Oracle Cloud Infrastructure Console

  Correct Answer: B

  Debugging Pods

  The first step in debugging a pod is taking a look at it. Check the current state of the pod and recent events

  with the following command:

  kubectl describe pods ${POD_NAME}

  Look at the state of the containers in the pod. Are they all Running? Have there been recent restarts?

  Continue debugging depending on the state of the pods.

  My pod stays pending

  If a pod is stuck in Pending it means that it can not be scheduled onto a node. Generally this is because

  there are insufficient resources of one type or another that prevent scheduling. Look at the output of the kubectl describe ... command above. There should be messages from the scheduler about why it can not schedule your pod. https://kubernetes.io/docs/tasks/debug-application-cluster/debug-pod-replication-controller/

• Question 15:

  You are tasked with developing an application that requires the use of Oracle Cloud Infrastructure (OCI)

  APIs to POST messages to a stream in the OCI Streaming service.

  Which statement is incorrect?

  A. The request must include an authorization signing string including (but not limited to) x-contentsha256, content-type, and content-length headers.

  B. The Content-Type header must be Set to application/j son

  C. An HTTP 401 will be returned if the client's clock is skewed more than 5 minutes from the server's.

  D. The request does not require an Authorization header.

  Correct Answer: A

  Emits messages to a stream. There's no limit to the number of messages in a request, but the total size of a message or request must be 1 MiB or less. The service calculates the partition ID from the message key and stores messages that share a key on the same partition. If a message does not contain a key or if the key is null, the service generates a message key for you. The partition ID cannot be passed as a parameter. POST /20180418/streams//messages Host: streaming-api.us-phoenix-1.oraclecloud.com { "messages": { { "key": null, "value": "VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cu" }, { "key": null, "value": "UGFjayBteSBib3ggd2l0aCBmaXZlIGRvemVuIGxpcXVvciBqdWdzLg==" } } } https://docs.cloud.oracle.com/en-us/iaas/api/#/en/streaming/20180418/Message/PutMessages

• Question 16:

  You encounter an unexpected error when invoking the Oracle Function named "myfunction" in application "myapp". Which can you use to get more information on the error?

  A. fn --debug invoke myapp myfunction

  B. DEBOG=l fn invoke myapp myfunction

  C. fn --verbose invoke myapp myfunction

  D. Call Oracle support with your error message

  Correct Answer: B

  Troubleshooting Oracle Functions

  If you encounter an unexpected error when using an Fn Project CLI command, you can find out more

  about the problem by starting the command with the string DEBUG=1 and running the command again.

  For example:

  $ DEBUG=1 fn invoke helloworld-app helloworld-func

  Note that DEBUG=1 must appear before the command, and that DEBUG must be in upper case.

• Question 17:

  You need to execute a script on a remote instance through Oracle Cloud Infrastructure Resource Manager. Which option can you use?

  A. Use /bin/sh with the full path to the location of the script to execute the script.

  B. It cannot be done.

  C. Download the script to a local desktop and execute the script.

  D. Use remote-exec

  Correct Answer: D

  Resource Manager is an Oracle Cloud Infrastructure service that allows you to automate the process of provisioning your Oracle Cloud Infrastructure resources. Using Terraform, Resource Manager helps you install, configure, and manage resources through the "infrastructure-as-code" model. With Resource Manager, you can use Terraform's remote exec functionality to execute scripts or commands on a remote computer. You can also use this technique for other provisioners that require access to the remote resource.

• Question 18:

  In order to effectively test your cloud-native applications, you might utilize separate environments (development, testing, staging, production, etc.). Which Oracle Cloud Infrastructure (OC1) service can you use to create and manage your infrastructure?

  A. OCI Compute

  B. OCI Container Engine for Kubernetes

  C. OCI Resource Manager

  D. OCI API Gateway

  Correct Answer: C

  Resource Manager is an Oracle Cloud Infrastructure service that allows you to automate the process of provisioning your Oracle Cloud Infrastructure resources. Using Terraform, Resource Manager helps you install, configure, and manage resources through the "infrastructure-as-code" model.

• Question 19:

  You are developing a serverless application with Oracle Functions and Oracle Cloud Infrastructure Object Storage- Your function needs to read a JSON file object from an Object Storage bucket named "inputbucket" in compartment "qa- compartment". Your corporate security standards mandate the use of Resource Principals for this use case. Which two statements are needed to implement this use case?

  A. Set up a policy with the following statement to grant read access to the bucket:allow dynamic-group read-file-dg to read objects in compartment qa-compartment where target .bucket .name=' input-bucket *

  B. Set up the following dynamic group for your function's OCID: Name: read-file-dg Rule: resource.id = `ocid1.fnfunc.oc1.phx.aaaaaaaakeaobctakezjz5i4ujj7g25q7sx5mvr55pms6f4da'

  C. Set up a policy to grant all functions read access to the bucket:allow all functions in compartment qacompartment to read objects in target.bucket.name='input-bucket'

  D. Set up a policy to grant your user account read access to the bucket:allow user XYZ to read objects in compartment qa-compartment where target .bucket, name-'input-bucket'

  E. No policies are needed. By default, every function has read access to Object Storage buckets in the tenancy

  Correct Answer: AB

  When a function you've deployed to Oracle Functions is running, it can access other Oracle Cloud Infrastructure resources. For example:

  -

  You might want a function to get a list of VCNs from the Networking service.

  -

  You might want a function to read data from an Object Storage bucket, perform some operation on the

  data, and then write the modified data back to the Object Storage bucket. To enable a function to access another Oracle Cloud Infrastructure resource, you have to include the function in a dynamic group, and then create a policy to grant the dynamic group access to that resource. https://docs.cloud.oracle.com/en-us/iaas/Content/Functions/Tasks/functionsaccessingociresources.htm

• Question 20:

  You are developing a distributed application and you need a call to a path to always return a specific JSON content deploy an Oracle Cloud Infrastructure API Gateway with the below API deployment specification.

  

  What is the correct value for type?

  A. STOCK_RESPONSE_BACKEND

  B. CONSTANT_BACKEND

  C. JSON_BACKEND

  D. HTTP_BACKEND

  Correct Answer: A

  "type": "STOCK_RESPONSE_BACKEND" indicates that the API gateway itself will act as the back end and return the stock response you define (the status code, the header fields and the body content). https://docs.cloud.oracle.com/en-us/iaas/Content/APIGateway/Tasks/ apigatewayaddingstockresponses.htm