How to install Ansible in Centos 7/RHEL 7?
How to install Ansible in Centos 7/RHEL 7? Install Ansible via Pip in RHEL/CENTOS Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus….
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Kibana 7.2 Install and configuration in RHEL 7/Centos
Install and Setup JDK 8+ Download and Install Kibana 7.X Configure Kibana 7.X How to start kibana service? Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I…
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How to use elastic search EC2 discovery plugin?
Problem To increase the performance in Elasticsearch, many times we add new nodes to Elasticsearch cluster and manually change the configuration file with new IP address, etc. so that it…
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Elastic Search Error – Node is started with node.data=false, but has shard data
[2019-07-11T09:59:18,013][ERROR][o.e.b.Bootstrap ] [es-master01] Exception java.lang.IllegalStateException: Node is started with node.data=false, but has shard data: [/home/ec2-user/elasticsearch-7.2.0/data/nodes/0/indices/6XsNftnbSbOnzPK3wOKc 0w/0]. Use ‘elasticsearch-node repurpose’ tool to clean up at org.elasticsearch.env.NodeEnvironment.ensureNoShardData(NodeEnvironment.java:1065) ~[elasticsearch-7.2.0.jar:7.2.0] at org.elasticsearch.env.NodeEnvironment.(NodeEnvironment.java:324) ~[elasticsearch-7.2.0.jar:7.2.0] Solution…
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Elastic Search Error – max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144]
Errors [2]: max virtual memory areas vm.max_map_count [65530] is too low, increase to at least [262144] Solution To make it persistent, you can add this line: $ sudo vi /etc/sysctl.conf…
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Elastic Search Error – max file descriptors [4096] for elasticsearch process is too low, increase to at least [65535]
Elastic Search Error – max file descriptors [4096] for elasticsearch process is too low, increase to at least [65535] Solution Temporary to the current login session To set ulimit value…
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How to create sample data to perform searches using elastic search?
Step 1 – Go to: http://www.json-generator.com/ Step 2 – Download and save as customers_full.json Step 3 – Open customers_full.json in sublimetext Remove the array brackets Find-Replace },{ with }\n{ in…
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What is difference between application/x-ndjson and application/json?
Lets understand what is json? JSON stands for JavaScript Object Notation JSON is a lightweight format for storing and transporting data JSON is often used when data is sent from…
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Elastic Search Error – The bulk request must be terminated by a newline
FIX – Add a New line in customers_full.json Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps…
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ElasticSearch Error – illegal_argument_exception – Rejecting mapping update to type
########### COMMAND ################# ########### OUTPUT ########### Solution Multiple mapping types are not supported in indices created in 6.0 The ability to have multiple mapping types per index has been removed…
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ElasticSearch Error – Content-Type header [application/x-www-form-urlencoded] is not supported
To fix this, add curl option -H ‘Content-Type: application/json’. This error is due to strict content-type checking introduced in ElasticSearch 6.0 Solution Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing…
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Understading Octopus Deploy Backup and restore process
Your Master Key When an Octopus Server is installed, we generate a special key used for encryption, called the master key. The master key is then encrypted asymmetrically, using DPAPI,…
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Prevent direct download of photos/video files from amazon s3
You can restrict access based on the HTTP referrer. It’s not bulletproof (Referrer can be spoofed) but it will stop casual downloads. Suppose you have a website with domain name…
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Ansible Include and Import with differences explanined!
This is one of the most frequest questions being asked in my workshop is that differences between using import or include in Ansible. For example import_role or include_role, what should…
Read more »Understanding Ansible Architecture using diagram
What is Ansible? Rajesh KumarI’m a DevOps/SRE/DevSecOps/Cloud Expert passionate about sharing knowledge and experiences. I have worked at Cotocus. I share tech blog at DevOps School, travel stories at Holiday…
Read more »Order of operations during Ansible playbook parsing explained!
We will delve into some specifics of how a playbook is parsed for Order of operations. Ansible can be assumed to be executed in a top to bottom order; that…
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Ansible Variable: How can I pass variable to ansible playbook in the command line?
It is possible to set variables at the command line using the –extra-vars (or -e) argument. Variables can be defined using a single quoted string (containing one or more variables)…
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How to specifying multiple groups in a playbook hosts specification?
By design, Ansible executes just one play at a time. Your playbook consists of two plays (the two items in the root-level YAML list defined by the playbook file). Method…
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Octopus deploy Package Deployment Feature Ordering
When Octopus deploys packages, it runs a series of actions implementing the conventions or features enabled for that step. The order of evaluation once the package is extracted is: BeforePreDeploy.*…
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Difference between ansible vars_files vs include_vars
Both of them have some commonalities but they solve different purposes. vars_files are read when the play starts. include_vars are read when the play reaches the task. Format vars_files: directive…
Read more »Configuration Transforms in Octopus Deploy explained!
Before understanding “Configuration Transforms” in octopus deploy, lets understand what is “Web.config Transformation” in visual studio. What is Web.config? Web.config is an application configuration file of The Official Microsoft ASP.NET…
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How to create a Nuget Package using NuGet Package Explorer?
What is NuGet Package Explorer? NuGet Package Explorer (NPE) is an application that makes it easy to create and explore NuGet packages. You can load a .nupkg or .snupkg file…
Read more »Understanding a world of DevOps from Richard Seroter
Introduction and Goals Hi, my name is Richard Seroter and welcome to this course on DevOps. We’re going to be covering the Big Picture of DevOps, hence the title, really…
Read more »Octopus Deploy – How to handle deployment errors and script failure response.
Each of your scripts will be bootstrapped by the open-source Calamari project to provide access to variables and helper functions. You can see how your scripts are bootstrapped in the…
Read more »Octopus Deploy – Send a Notification When Deployments Fail
If you are using Octopus Deploy as part of a continuous delivery pipeline, you’ll probably find that deployments don’t fail very often. This means, you need to send an email…
Read more »Octopus Deploy – Deployment Examples and Sample Projects
Deploying software with Octopus Deploy involves packaging your applications and configuring your infrastructure. With those two steps completed, you need to define your deployment process by creating a project, adding steps and configuration variables, and creating releases. The section goes…
Read more »Octopus Deploy – Run Multiple Processes steps on a Tentacle Simultaneously and Parallel
For each step that you define in you deployment processes, you can set conditions for greater control over the step’s execution. You can set conditions to: Run the step on…
Read more »Splunk frequently asked questions!!!
Question – How often does the forwarder send data to indexer?Answer – The forwarder sends data immediately when it becomes available. There is no certain interval that it waits or…
Read more »How to use two github account on the same computer?
Step 1 – How to generate a ssh key pair? $ ssh-keygen -t rsa -C “devops@RajeshKumar.xyz” Step 2 – Upload 2 different public key in 2 github accounts. Step 3…
Read more »What Is HTML?
HTML is a markup language for creating web documents / pages 1.Hyper Text Markup Language 2.Markup language – Uses a set of markup tags 3.NOT a programming language HTML Tags…
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