Click to the Exhibit button.
Referring to the exhibit, which OpenStack service provides the UI shown in the exhibit?
The UI shown in the exhibit is the OpenStack Horizon dashboard. Horizon is the web-based user interface (UI) for OpenStack, providing administrators and users with a graphical interface to interact with the cloud environment. Through Horizon, users can manage resources like instances, networks, and storage, which is evident in the displayed metrics (Instances, VCPUs, RAM) for the project.
You want to limit the memory, CPU, and network utilization of a set of processes running on a Linux host.
Which Linux feature would you configure in this scenario?
You want to limit the memory, CPU, and network utilization of a set of processes running on a Linux host.
Which Linux feature would you configure in this scenario?
Linux provides several features to manage system resources and isolate processes. Let's analyze each option:
A . virtual routing and forwarding instances
Incorrect: Virtual Routing and Forwarding (VRF) is a networking feature used to create multiple routing tables on a single router or host. It is unrelated to limiting memory, CPU, or network utilization for processes.
B . network namespaces
Incorrect: Network namespaces are used to isolate network resources (e.g., interfaces, routing tables) for processes. While they can help with network isolation, they do not directly limit memory or CPU usage.
C . control groups
Correct: Control Groups (cgroups) are a Linux kernel feature that allows you to limit, account for, and isolate the resource usage (CPU, memory, disk I/O, network) of a set of processes. cgroups are commonly used in containerization technologies like Docker and Kubernetes to enforce resource limits.
D . slicing
Incorrect: 'Slicing' is not a recognized Linux feature for resource management. This term may refer to dividing resources in other contexts but is not relevant here.
Why Control Groups?
Resource Management: cgroups provide fine-grained control over memory, CPU, and network utilization, ensuring that processes do not exceed their allocated resources.
Containerization Foundation: cgroups are a core technology behind container runtimes like containerd and orchestration platforms like Kubernetes.
JNCIA Cloud Reference:
The JNCIA-Cloud certification covers Linux features like cgroups as part of its containerization curriculum. Understanding cgroups is essential for managing resource allocation in cloud environments.
For example, Juniper Contrail integrates with Kubernetes to manage containerized workloads, leveraging cgroups to enforce resource limits.
Linux Kernel Documentation: Control Groups
Juniper JNCIA-Cloud Study Guide: Linux Features
When considering OpenShift and Kubernetes, what are two unique resources of OpenShift? (Choose two.)
OpenShift extends Kubernetes by introducing additional resources and abstractions to simplify application development and deployment. Let's analyze each option:
A . routes
Correct:
Routes are unique to OpenShift and provide a way to expose services externally by mapping a hostname to a service. They are built on top of Kubernetes Ingress but offer additional features like TLS termination and wildcard support.
B . build
Correct:
Builds are unique to OpenShift and represent the process of transforming source code into container images. OpenShift provides build configurations and strategies (e.g., Docker, S2I) to automate this process, which is not natively available in Kubernetes.
C . ingress
Incorrect:
Ingress is a standard Kubernetes resource used to manage external access to services. While OpenShift uses Ingress as the foundation for its Routes, Ingress itself is not unique to OpenShift.
D . services
Incorrect:
Services are a core Kubernetes resource used to expose applications internally within the cluster. They are not unique to OpenShift.
Why These Resources?
Routes: Extend Kubernetes Ingress to provide advanced external access capabilities, such as custom domain mappings and TLS termination.
Builds: Simplify the process of building container images directly within the OpenShift platform, enabling streamlined CI/CD workflows.
JNCIA Cloud Reference:
The JNCIA-Cloud certification covers OpenShift's unique resources as part of its curriculum on container orchestration platforms. Understanding the differences between OpenShift and Kubernetes resources is essential for leveraging OpenShift's full capabilities.
For example, Juniper Contrail integrates with OpenShift to provide advanced networking features, ensuring secure and efficient traffic routing for Routes and Builds.
OpenShift Documentation: Routes and Builds
Juniper JNCIA-Cloud Study Guide: OpenShift vs. Kubernetes
Which two statements about Kubernetes are correct? (Choose two.)
Kubernetes is an open-source container orchestration platform that automates the deployment, scaling, and management of containerized applications. Let's analyze each statement:
A . Kubernetes is compatible with the container open container runtime.
Correct: Kubernetes supports the Open Container Initiative (OCI) runtime standards, which ensure compatibility with various container runtimes like containerd, cri-o, and others. This flexibility allows Kubernetes to work with different container engines beyond just Docker.
B . Kubernetes requires the Docker daemon to run Docker containers.
Incorrect: While Kubernetes historically used Docker as its default container runtime, it no longer depends on the Docker daemon. Instead, Kubernetes uses the Container Runtime Interface (CRI) to interact with container runtimes like containerd or cri-o. Docker's runtime has been replaced by containerd in most modern Kubernetes deployments.
C . A container is the smallest unit of computing that you can manage with Kubernetes.
Correct: In Kubernetes, a container represents the smallest deployable unit of computing. Containers encapsulate application code, dependencies, and configurations. Kubernetes manages containers through higher-level abstractions like Pods, which are groups of one or more containers.
D . A Kubernetes cluster must contain at least one control plane node.
Incorrect: While a Kubernetes cluster typically requires at least one control plane node to manage the cluster, this statement is incomplete. A functional Kubernetes cluster also requires at least one worker node to run application workloads. Both control plane and worker nodes are essential for a fully operational cluster.
Why These Answers?
Compatibility with OCI Runtimes: Kubernetes' support for OCI-compliant runtimes ensures flexibility and avoids vendor lock-in.
Containers as Smallest Unit: Understanding that containers are the fundamental building blocks of Kubernetes is crucial for designing and managing applications in a Kubernetes environment.
JNCIA Cloud Reference:
The JNCIA-Cloud certification covers Kubernetes as part of its container orchestration curriculum. Understanding Kubernetes architecture, compatibility, and core concepts is essential for deploying and managing containerized applications in cloud environments.
For example, Juniper Contrail integrates with Kubernetes to provide advanced networking and security features for containerized workloads. Proficiency with Kubernetes ensures seamless operation of cloud-native applications.
Kubernetes Documentation: Container Runtimes
Juniper JNCIA-Cloud Study Guide: Kubernetes
You just uploaded a qcow2 image of a vSRX virtual machine in OpenStack.
In this scenario, which service stores the virtual machine (VM) image?
OpenStack provides various services to manage cloud infrastructure resources, including virtual machine (VM) images. Let's analyze each option:
A . Glance
Correct: Glance is the OpenStack service responsible for managing and storing VM images. It provides a repository for uploading, discovering, and retrieving images in various formats, such as qcow2, raw, or ISO.
B . Ironic
Incorrect: Ironic is the OpenStack bare-metal provisioning service. It is used to manage physical servers, not VM images.
C . Neutron
Incorrect: Neutron is the OpenStack networking service that manages virtual networks, routers, and IP addresses. It does not store VM images.
D . Nova
Incorrect: Nova is the OpenStack compute service that manages the lifecycle of virtual machines. While Nova interacts with Glance to retrieve VM images for deployment, it does not store the images itself.
Why Glance?
Image Repository: Glance acts as the central repository for VM images, enabling users to upload, share, and deploy images across the OpenStack environment.
Integration with Nova: When deploying a VM, Nova retrieves the required image from Glance to create the instance.
JNCIA Cloud Reference:
The JNCIA-Cloud certification covers OpenStack services, including Glance, as part of its cloud infrastructure curriculum. Understanding Glance's role in image management is essential for deploying and managing virtual machines in OpenStack.
For example, Juniper Contrail integrates with OpenStack Glance to provide advanced networking features for VM images stored in the repository.
OpenStack Glance Documentation
Juniper JNCIA-Cloud Study Guide: OpenStack Services
