Best DevOps Tools of 2019

Git is an open source, distributed and the most popular software versioning system. It works on client server model, which basically means that there is a central server which holds main repository of code. Code can be downloaded from main repository simultaneously by various clients or developers. Git is developed by Linus Torvalds. Git facilitates teams which are located at geographically different places to collaborate on same project. Popular companies like Google, Facebook, Microsoft, Netflix extensively use Git in their CI/CD pipelines.

Docker is a containerization technology. Containers consist of all the applications with all of its dependencies. These containers can be deployed on any machine without caring about underlying host details. Containers can be a .net application or a website along with its dependencies like .net or lamp stack in case of website application. These containers are used to automate the deployment process of application in production and non-production environment.

Selenium is open source, automated testing framework. Selenium is used majorly to automate the testing of web applications. We can define test in selenium which we want to test against our application. Selenium can repeatedly apply those test to our application without manual intervention and generate reports. These reports can be used by testing individuals to see if application is behaving correctly or not.

Jenkins is an open source automation server written in java. Jenkins provides automation of continuous delivery part. Jenkins is used in creating continuous delivery pipelines. To give you an example here is a scenario wherein a Jenkins server will take our application container from development environment and make it accessible to testing environment, QA environment or any other non-production environment in the beginning. Jenkins server is in the middle of whole CI/CD pipeline. It automates this whole process which means whenever a developer will commit a change in a code that code will automatically be visible to testing server or QA team. They then can provide instantaneous feedback on these changes. Jenkins is used by Microsoft, Redhat, Rackspace, to name a few.

Ansible is an open source application which is used for automated software provisioning, configuration management and application deployment. Ansible is the backbone of controlling an automated cluster environment consisting of many machines. Ansible works on client server model. Client acts as a master which is centre point in our cluster and provides centralized control of all client machines (slaves) that are connected to it. We can give any command to any client machine or deploy any application to more than one machine from a single master machine. Ansible only requires SSH for communication so it does not need any software dependency to run. Ansible works on Unix.

Puppet is an open source software configuration management, automated provisioning tool. It is an alternative to Ansible and provides better control over client machines. Puppet comes up with GUI which makes it easy to use than Ansible. Puppet is cross platform, it runs on both Unix and Microsoft Windows. Puppet uses a manifest file and applies those specifications across all machines. Unlike Ansible, Puppet is agent-based tool.Puppet master runs on master machine and Puppet agent runs on all client machines. Puppet is used by Microsoft, Google, Accenture, etc.

Nagios is used for continuous monitoring of infrastructure. Nagios provides server monitoring, application monitoring, network monitoring. By Nagios we can monitor whole data centre from a single server.We can see whether switches are working correctly, servers are not having too much load or if any part of application is down. It provides a nice GUI interface to check various details like how much memory is used, what is fan speed, routing tables of switches, or state of SQL server. Nagios has a modular design. It supports NRPE plugins which can be used to addmonitoring parameteron existing Nagios. There are various plugins available on the internet which can be used freely to add features to Nagios. Nagios is most popular tool in continuous monitoring.

Chef is a configuration management tool. Chef is used to manage configuration like creating or removing a user, adding SSH key to a user present on multiple nodes, installing or removing a service, etc. We can manage upto 10,000 nodes by using chef. These changes are pushed by cookbooks or recipes. Chef has three components viz. Chef server, workstation and nodes. Chef server is a central point where all details of our Chef infrastructure resides. Chef workstation holds recipes or cookbooks which pushes particular configuration to our chef infrastructure. Nodes are simple machines which are configured by using chef. Chef has API support from AWS, Azure, Rackspace, which makes it easy to use with infrastructure as a code methodology.

SVN or Subversion is an open source, centralized software versioning & revision control system. SVN is an alternative of GIT. SVN is a centralized system which means every time if a team member or client wants to make changes in the code he has to inform the central server or repo about these changes. To use a SVN repo, client needs to connect to the central server. It can check out the code to download the repo from server. Client than moves on to make changes in this code and commit this change by informing the central repo. From central repo these changes will be visible to other team members or clients.

Rational ClearCase manages changes across the software lifecycle. ClearCase is used in Software configuration management of source code. ClearCase is used in both hardware and software development. The centre of ClearCase is a secure data repository. It has data that is shared by all users including accounting data and historical data on development processes itself. It shows details like which user implemented which version, when and why. There are 3 products of ClearCase, Rational ClearCase is for medium to large teams, Rational ClearCase LT is useful for small to medium team, Rational ClearCase multisite is used by geographically distributed teams.

Maven is build automation tool. It automates software build process & dependencies resolution. A Maven project is configured using a project object model or POM.XML file which describes the build process and the software project, its dependencies on external modules and components, build order, directories. Maven can dynamically download these external modules & Maven plugins during the build process itself. Maven can build and manage projects on Java, C#, Scala, Ruby and other languages. Maven is majorly used by Apache Foundation to automate build of some of its large projects like Apache Hadoop.

Apache Ant is software tool used for automation of software build process. Apache Ant is inspired by Unix make utility. Apache Ant uses an XML file build.xml in place of makefile which is used by make utility for build processes. It automates repetitive tasks in build process and generates documentation. Ant builds are based on three blocks viz. tasks, targets, and extension points. Ant supports many third-party extensions like Eclipse IDE and NetBeans IDE.

Kubernetes is an open source container orchestration tool. It is developed by Google. It is used in continuous deployment and auto scaling of container clusters. It increases fault tolerance, load balancing in a container cluster. Kubernetes maintains a desired state of cluster, this desired state is described in YAML file. YAML file contains state of pods or slave nodes and replication unit for a cluster. Kubernetes uses this YAML file to maintain a desired state of cluster for example in case of one pod is serving more requests than other pod then it can automatically distribute this load to other pods, in case of one machine fails than it can configure another pod to replace its place hence ensuring fault tolerance, load balancing and high availability in a cluster. Kubernetes is used in high performance data centres like that of Google, Facebook, and Amazon Web Services.