***Linkerd Interview questions and answers***

Table of Contents

1) Who owns Linkerd?

the Cloud Native Computing Foundation
Linkerd is hosted by the Cloud Native Computing Foundation (CNCF). The CNCF owns the trademark; the copyright is held by the Linkerd authors themselves.

2) When was Linkerd created?

2016
Linkerd is a service mesh that provides critical observability, security, and reliability features to cloud native applications without requiring code changes. The project was created in 2016 by Buoyant and joined CNCF in early 2017 as the foundation’s fifth project.

3) What language is Linkerd?

It became the original “service mesh” when its creator Buoyant first coined the term in 2016. Like Twitter’s Finagle, on which it was based, Linkerd was first written in Scala and designed to be deployed on a per-host basis.

4) Is Linkerd a service mesh?

Linkerd is a service mesh for Kubernetes. It makes running services easier and safer by giving you runtime debugging, observability, reliability, and security—all without requiring any changes to your code.

5) How do I run Linkerd?

Getting Started
Step 0: Setup. …
Step 1: Install the CLI. …
Step 2: Validate your Kubernetes cluster. …
Step 3: Install Linkerd onto the cluster. …
Step 4: Explore Linkerd. …
Step 5: Install the demo app. …
Step 6: Watch it run.

6) Does Linkerd require Kubernetes?

Before we can do anything, we need to ensure you have access to modern Kubernetes cluster and a functioning kubectl command on your local machine. (If you don’t already have a Kubernetes cluster, one easy option is to run one on your local machine.

7) Why do I need a service mesh?

A service mesh is a software infrastructure layer for controlling and monitoring internal, service-to-service traffic in microservices applications. Service mesh provides some of the middleware and some of the components that enable service-to-service communication, such as dynamic discovery.

8) What problems does a service mesh solve?

A service mesh solves some of the challenges introduced by distributed microservices by abstracting necessary functions (service discovery, connection encryption, error and failure handling, and latency detection and response) to a separate entity called proxy.

9) Is Linkerd better than Istio?

Linkerd is primarily more performant than Istio due to its targeted approach and lightweight proxy. Its data plane is 2–5 times faster, depending on the scenario. As to resource consumption, Istio consumes around 2–3 times the memory and 8 times the CPU of Linkerd.

10) Why do I need Linkerd?

Why do I need a service mesh? If you are building applications on Kubernetes, then a service mesh like Linkerd provides critical observability, reliability, and security features with one big advantage: the application doesn’t need to implement these features, or even to be aware that the service mesh is there!

12) What is nginx service mesh?

NGINX Service Mesh is a fully integrated lightweight service mesh that leverages a data plane powered by NGINX Plus to manage container traffic in Kubernetes environments.

13) What is service mesh in Kubernetes?

A Kubernetes service mesh is a tool that inserts security, observability, and reliability features to applications at the platform layer instead of the application layer. Service mesh technology predates Kubernetes.

14) What is Knative in Kubernetes?

Knative (pronounced kay-nay-tiv) is an open source community project which adds components for deploying, running, and managing serverless, cloud-native applications to Kubernetes. The serverless cloud computing model can lead to increased developer productivity and reduced operational costs.

15) What is sidecar pattern?

The sidecar pattern is a single-node pattern made up of two containers. The first is the application container. It contains the core logic for the application. Without this container, the application would not exist. In addition to the application container, there is a sidecar container.

16) What is a sidecar proxy?

A sidecar proxy is an application design pattern which abstracts certain features, such as inter-service communications, monitoring and security, away from the main architecture to ease the tracking and maintenance of the application as a whole.

17) What is envoy in Istio?

Envoy. Istio uses an extended version of the Envoy proxy. Envoy is a high-performance proxy developed in C++ to mediate all inbound and outbound traffic for all services in the service mesh. Envoy proxies are the only Istio components that interact with data plane traffic.

18) What is kubectl used for?

The Kubernetes command-line tool, kubectl, allows you to run commands against Kubernetes clusters. You can use kubectl to deploy applications, inspect and manage cluster resources, and view logs.

19) What is AWS app mesh?

AWS App Mesh is a service mesh that provides application-level networking to make it easy for your services to communicate with each other across multiple types of compute infrastructure. App Mesh gives end-to-end visibility and high-availability for your applications.

20) What is AWS app mesh?

21) What is Kuma used for?

Kuma is a platform agnostic open-source control plane for service mesh and microservices management, with support for Kubernetes, VM, and bare metal environments. Kuma helps implement a service mesh approach to distributed deployments as part of the move from monolithic architectures to microservices.

22) Is Traefik a service mesh?

Traefik Mesh is a straight-forward, easy to configure, and non-invasive service mesh that allows visibility and management of the traffic flows inside any Kubernetes cluster.

23) Does Linkerd use envoy?

Why doesn’t Linkerd use Envoy? Envoy is a complex general-purpose proxy. Linkerd uses a simple and ultralight “micro-proxy” called Linkerd2-proxy that is built specifically for the service mesh sidecar use case. This allows Linkerd to be significantly smaller and simpler than Envoy-based service meshes.

24) What is Kubernetes sidecar pattern?

When you use the sidecar pattern, your Kubernetes pod holds the container that runs your app alongside the container that runs the Sensu agent. These containers share the same network space so your applications can talk to Sensu as if they were running in the same container or host.

25) What is Linkerd in Kubernetes?

26) What problems does Istio solve?

And Kubernetes/Istio is a technical solution to deal with the issues created by moving to microservices. As a deliverable for microservices, containers solve the problem of environmental consistency and allow for more granularity in limiting application resources. They are widely used as a vehicle for microservices.

27) Why is Linkerd not Envoy?

In short: Linkerd doesn’t use Envoy because using Envoy wouldn’t allow us to build the lightest, simplest, and most secure Kubernetes service mesh in the world.

28) What is Linkerd in Kubernetes?

29) What is Knative in Kubernetes?

30) What is Consul process?

This topic provides an overview of the Consul agent, which is the core process of Consul. The agent maintains membership information, registers services, runs checks, responds to queries, and more. The agent must run on every node that is part of a Consul cluster. Agents run in either client or server mode.

31) Who’s Using Service Mesh

Results from the Voice of the Enterprise: DevOps, Workloads & Key Projects 2020 survey tell us that 16% of respondents had adopted service mesh across their entire IT organizations, and 20% had adopted service mesh at the team level.

32) What is Red Hat service mesh?

Red Hat® OpenShift® Service Mesh provides a uniform way to connect, manage, and observe microservices-based applications. It provides behavioral insight into—and control of—the networked microservices in your service mesh.

33) What is sidecar pattern?

34) What is mesh architecture?

In a mesh architecture, every node is connected to every other node in a mesh-like lattice work of connections (see Figure 13.1). An increase in the number of nodes increases the quality of the mesh. Mesh networks offer a high degree of reliability.

35) What is API mesh?

Renvoize said the result of the work is what the bank calls ‘API Mesh’, which she describes as a “multicloud and cloud hybrid platform that allows [developers] to access integration capabilities across the hosting zones within the bank.”

36) What is Kuma service mesh?

Kuma is an enterprise-grade service mesh that runs on both Kubernetes and VMs on any cloud.

37) What is Kuma used for?

38) What is difference between POD and container?

Pod is just a co-located group of container and an Kubernetes object. Instead of deploying them separate you can do deploy a pod of containers . Best practices is that you should not actually run multiple processes via single container and here is the place where pod idea comes to a place.

39) Does Istio require Kubernetes?

Istio is currently the most popular service mesh implementation, relying on Kubernetes but also scalable to virtual machine loads.

40) What is API data?

API is an acronym for Application Programming Interface that software uses to access data, server software or other applications and have been around for quite some time. In layman’s terms, it is a software intermediary that allows two applications to talk to each other.

41) What is envoy service mesh?

Originally created at Lyft, Envoy is a high-performance data plane designed for service mesh architectures. Lyft open sourced it and donated it to the CNCF, where it is now one of the CNCF’s graduated open source projects.

42) Which of the following are possible with Istio service mesh?

Istio service mesh is a sidecar container implementation of the features and functions needed when creating and managing microservices. Monitoring, tracing, circuit breakers, routing, load balancing, fault injection, retries, timeouts, mirroring, access control, rate limiting, and more, are all a part of this.

43) Is Istio hard?

For a very long time, Istio has been criticized as notoriously complex and hard to use. As someone who worked on the project for over four years, I agreed with this statement in the first two years of Istio.

44) What is API example?

API is the acronym for Application Programming Interface, which is a software intermediary that allows two applications to talk to each other. Each time you use an app like Facebook, send an instant message, or check the weather on your phone, you’re using an API.

45) What is SDK programming?

A software development kit (SDK) is a set of tools provided by the manufacturer of (usually) a hardware platform, operating system (OS), or programming language.

46) How do SDK work?

A software development kit (SDK) is a set of tools that provides a developer with the ability to build a custom app which can be added on, or connected to, another program. SDKs allow programmers to develop apps for a specific platform.

47) Is SDK an IDE?

An SDK provides the tools for programming while an IDE only provides an interface. Some SDKs already include an IDE. An SDK is necessary for programming while an IDE is only optional. There are a lot of IDEs to choose from but not the SDK.

48) Why is API needed?

APIs are needed to bring applications together in order to perform a designed function built around sharing data and executing pre-defined processes. They work as the middle man, allowing developers to build new programmatic interactions between the various applications people and businesses use on a daily basis.

49) What is the SOAP API?

What Is a SOAP API? SOAP is a standard communication protocol system that permits processes using different operating systems like Linux and Windows to communicate via HTTP and its XML. SOAP based APIs are designed to create, recover, update and delete records like accounts, passwords, leads, and custom objects.

50) What is difference between API and REST API?

The primary goal of API is to standardize data exchange between web services. Depending on the type of API, the choice of protocol changes. On the other hand, REST API is an architectural style for building web services that interact via an HTTP protocol.