Nigel Uys

Nigel Uys

1673432640

Ansible Best Practises

Ansible Best Practises

If infrastructures are to be treated as a code than projects that manage them must be treated as software projects. As your infrastructure code gets bigger and bigger you have more problems to deal with. Code layout, variable precedence, small hacks here and there. Therefore, the organization of your code is very important, and in this repository you can find some of the best practices (in our opinion) to manage your infrastructure code. Problems that are addressed are:

  • Overall organization
  • How to manage external roles
  • Usage of variables
  • Naming
  • Staging
  • Complexity of plays
  • Encryption of data (e.g. passwords, certificates)
  • Installation of ansible and module dependencies

TL;DR

  • Do not manage external roles in your repository manually, use ansible-galaxy
  • Do not use pre_task, task or post_tasks in your play, use roles to reuse the code
  • Keep all your variables in one place, if possible
  • Do not use variables in your play
  • Use variables in the roles instead of hard-coding
  • Keep the names consistent between groups, plays, variables, and roles
  • Different environments (development, test, production) must be close as possible, if not equal
  • Do not put your password or certificates as plain text in your git repo, use ansible-vault for encrypting
  • Use tags in your play
  • Keep all your ansible dependencies in a single place and make the installation dead-simple

1. Directory Layout

This is the directory layout of this repository with an explanation.

production.ini            # inventory file for production stage
development.ini           # inventory file for development stage
test.ini                  # inventory file for test stage
vpass                     # ansible-vault password file
                          # This file should not be committed into the repository
                          # therefore file is in ignored by git
group_vars/
    all/                  # variables under this directory belongs all the groups
        apt.yml           # ansible-apt role variable file for all groups
    webservers/           # here we assign variables to webservers groups
        apt.yml           # Each file will correspond to a role i.e. apt.yml
        nginx.yml         # ""
    postgresql/           # here we assign variables to postgresql groups
        postgresql.yml    # Each file will correspond to a role i.e. postgresql
        postgresql-password.yml   # Encrypted password file
plays/
    ansible.cfg           # Ansible.cfg file that holds all ansible config
    webservers.yml        # playbook for webserver tier
    postgresql.yml        # playbook for postgresql tier

roles/
    roles_requirements.yml# All the information about the roles
    external/             # All the roles that are in git or ansible galaxy
                          # Roles that are in roles_requirements.yml file will be downloaded into this directory
    internal/             # All the roles that are not public

extension/
    setup/                 # All the setup files for updating roles and ansible dependencies

2. How to Manage Roles

It is a bad habit to manage the roles that are developed by other developers, in your git repository manually. It is also important to separate them so that you can distinguish those that are external and can be updated vs those that are internal. Therefore, you can use ansible-galaxy for installing the roles you need, at the location you need, by simply defining them in the roles_requirements.yml:

---
- src: ANXS.build-essential
  version: "v1.0.1"

Roles can be downloaded/updated with this command:

./extensions/setup/role_update.sh

This command will delete all external roles and download everything from scratch. It is a good practice, as this will not allow you to make changes in the roles.

3. Keep your plays simple

If you want to take the advantage of the roles, you have to keep your plays simple. Therefore do not add any tasks to your main play. Your play should only consist of the list of roles that it depends on. Here is an example:

---

- name: postgresql.yml | All roles
  hosts: postgresql
  sudo: True

  roles:
    - { role: common,                   tags: ["common"] }
    - { role: ANXS.postgresql,          tags: ["postgresql"] }

As you can see there are also no variables in this play, you can use variables in many different ways in ansible, and to keep it simple and easier to maintain do not use variables in plays. Furthermore, use tags, they give wonderful control over role execution.

4. Stages

Most likely you will need different stages (e.g. test, development, production) for the product you are either developing or helping to develop. A good way to manage different stages is to have multiple inventory files. As you can see in this repository, there are three inventory files. Each stage you have must be identical as possible, that also means, you should try to use few as possible host variables. It is best to not use at all.

5. Variables

Variables are wonderful, they allow you to use all this existing code by just setting some values. Ansible offers many different ways to use variables. However, soon as your project starts to get bigger, and more you spread variables here and there, more problems you will encounter. Therefore it is good practice to keep all your variables in one place, and this place happen to be group_vars. They are not host dependent, so it will help you to have a better staging environment as well. Furthermore, if you have internal roles that you have developed, keep the variables out of them as well, so you can reuse them easily.

6. Name consistency

If you want to maintain your code, keep the name consistent between your plays, inventories, roles and group variables. Use the name of the roles to separate different variables in each group. For instance, if you are using the role nginx under webservers play, variables that belong to nginx should be located under group_vars/webservers/nginx.yml. What this effectively means is that group_vars supports directory and every file inside the group will be loaded. You can, of course, put all of them in a single file as well, but this is messy, therefore don't do it.

7. Encrypting Passwords and Certificates

It is most likely that you will have a password or certificates in your repository. It is not a good practice to put them in a repository as plain text. You can use ansible-vault to encrypt sensitive data. You can refer to postgresql-password.yml in group variables to see the encrypted file and postgresql-password-plain.yml to see the plain text file, commented out. To decrypt the file, you need the vault password, which you can place in your root directory but it MUST NOT be committed to your git repository. You should share the password with your coworkers with some other method than committing to git a repo.

There is also git-crypt that allow you to work with a key or GPG. It's more transparent on daily work than ansible-vault

8. Project Setup

As it should be very easy to set-up the work environment, all required packages that ansible needs, as well as ansible should be installed very easily. This will allow newcomers or developers to start using ansible project very fast and easily. Therefore, python_requirements.txt file is located at:

extensions/setup/python_requirements.txt

This structure will help you to keep your dependencies in a single place, as well as making it easier to install everything including ansible. All you have to do is to execute the setup file:

./extensions/setup/setup.sh

Running the Code

Code in this repo is functional and tested. To run it, you need to install ansible and all the dependencies. You can do this simply by executing:

./extensions/setup/setup.sh
  • If you already have ansible, and you do not want to go through the installation simply create a vpass text file in the root directory and add the secret code (123456)
  • To install roles execute the role_update.sh which will download all the roles
./extensions/setup/role_update.sh
  • Go to the plays directory and then execute the following command ( do not forget to change the host address in the development.ini )
ansible-playbook -i ../development.ini webservers.yml

Download Details:

Author: Enginyoyen
Source Code: https://github.com/enginyoyen/ansible-best-practises 
License: MIT license

#ansible #infrastructure #automate 

What is GEEK

Buddha Community

Ansible Best Practises
bindu singh

bindu singh

1647351133

Procedure To Become An Air Hostess/Cabin Crew

Minimum educational required – 10+2 passed in any stream from a recognized board.

The age limit is 18 to 25 years. It may differ from one airline to another!

 

Physical and Medical standards –

  • Females must be 157 cm in height and males must be 170 cm in height (for males). This parameter may vary from one airline toward the next.
  • The candidate's body weight should be proportional to his or her height.
  • Candidates with blemish-free skin will have an advantage.
  • Physical fitness is required of the candidate.
  • Eyesight requirements: a minimum of 6/9 vision is required. Many airlines allow applicants to fix their vision to 20/20!
  • There should be no history of mental disease in the candidate's past.
  • The candidate should not have a significant cardiovascular condition.

You can become an air hostess if you meet certain criteria, such as a minimum educational level, an age limit, language ability, and physical characteristics.

As can be seen from the preceding information, a 10+2 pass is the minimal educational need for becoming an air hostess in India. So, if you have a 10+2 certificate from a recognized board, you are qualified to apply for an interview for air hostess positions!

You can still apply for this job if you have a higher qualification (such as a Bachelor's or Master's Degree).

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Katlynn Schaden

Katlynn Schaden

1667747700

Awesome Ansible List

Awesome Ansible

A collaborative curated list of awesome Ansible resources, tools, Roles, tutorials and other related stuff.

Ansible is an open source toolkit, written in Python, it is used for configuration management, application deployment, continuous delivery, IT infrastructure automation and automation in general.

Official resources

Official resources by and for Ansible.

Community

Places where to chat with the Ansible community

Tutorials

Tutorials and courses to learn Ansible.

Books

Books about Ansible.

Videos

Video tutorials and Ansible training.

Tools

Tools for and using Ansible.

  • Ansible Tower - Ansible Tower by Red Hat helps you scale IT automation, manage complex deployments and speed productivity. Extend the power of Ansible to your entire team.
  • AWX - AWX provides a web-based user interface, REST API, and task engine built on top of Ansible. It is the upstream project for Tower, a commercial derivative of AWX.
  • Ansible Lint - Checks Playbooks for best practices and behavior that could potentially be improved.
  • Ansible Later - Another best practice scanner. Checks Playbooks and Roles for best practices and behavior that could potentially be improved.
  • Ansible Doctor - Simple annotation like documentation generator for Ansible roles based on Jinja2 templates.
  • Ansible cmdb - Takes the output of Ansible's fact gathering and converts it into a static HTML page.
  • ARA - ARA Records Ansible playbooks and makes them easier to understand and troubleshoot with a reporting API, UI and CLI.
  • Mitogen for Ansible - Speed up Ansible substantially with Mitogen.
  • Molecule - Molecule aids in the development and testing of Ansible roles.
  • Packer Ansible Provisioner - This Provisioner can be used to automate VM Image creation via Packer with Ansible.
  • Excel Ansible Inventory - Turn any Excel Spreadsheet into an Ansible Inventory.
  • terraform.py - Ansible dynamic inventory script for parsing Terraform state files.
  • ansible-navigator - A text-based user interface (TUI) for Ansible.
  • squest - Self-service portal for Ansible Tower job templates.
  • ansible-bender - Tool which bends containers using Ansible playbooks and turns them into container images.
  • ansible-runner - A tool and python library that helps when interfacing with Ansible directly or as part of another system whether that be through a container image interface, as a standalone tool, or as a Python module that can be imported.
  • ansible-builder - Using Ansible content that depends on non-default dependencies can be tricky. Packages must be installed on each node, play nicely with other software installed on the host system, and be kept in sync.
  • kics - SAST Tool that scans your ansible infrastructure as code playbooks for security vulnverables, compliance issues and misconfigurations.
  • php-ansible Library - OOP-Wrapper for Ansible, making Ansible available in PHP.
  • TD4A - Design aid for building and testing jinja2 templates, combines data in yaml format with a jinja2 template and render the output.
  • Ansible Playbook Grapher - Command line tool to create a graph representing your Ansible playbook plays, tasks and roles.
  • ansible-doc-extractor - A tool that extracts documentation from Ansible modules in the HTML form.
  • Ansible Semaphore - Ansible Semaphore is a modern UI for Ansible.

Blog posts and opinions

Best practices and other opinions on Ansible.

German

Playbooks, Roles and Collections

Awesome production ready Playbooks, Roles and Collections to get you up and running.

Download Details:

Author: ansible-community
Source Code: https://github.com/ansible-community/awesome-ansible

License: CC0-1.0 license

#ansible 

BSEtec Private Limited

BSEtec Private Limited

1634193233

FAQs On a Udemy clone app That You Should Know Before Buying!

BSETEC's Udemy clone app based on formalized teaching but with the help of electronic resources is known as E-learning.E-learning, also referred to as online learning or electronic learning, is the acquisition of knowledge which takes place through electronic technologies .

Udemy, which was founded more than a decade ago, has established itself as a global leader in the online teaching industry. People in our digital era rely on technology and devices for nearly everything, including education. When it comes to online learning, or eLearning, which is regarded as a lifesaver– capable of sustaining the educational environment even during the Covid-19 pandemic– it has evolved into a platform bursting with potential, not only for students but also for tutors, educators, and instructors. Furthermore, when compared to traditional educational techniques, the flexibility and customization given by online tutoring software like Expertplus LMS are unrivalled. As a result, it is gradually becoming an important component of the learning process, which is why eLearning is here to stay– even after the epidemic has passed, it is a huge increase in the number of eLearning applications and websites, and most businesses are choosing for Udemy Clone App instead of starting from scratch.

BigBlueButton Technology – Make Efficient Interaction with LMS

How can I get started with your own online tutoring company?

To use the Udemy Clone App script to establish an online tutoring marketplace similar to Udemy, bear the following factors in mind:

  • How to define your target audience?– Before you start developing your Learning Management System, you should think about who you're going to serve, what their background is, what kind of job they want to do, and what their career goals are. These are all things to consider before you begin the development process. As a result, you must be clear about who you are developing your app for.
  • Why have a clear set of goals and objectives in mind?– If you're creating an app for eLearning, you should have a solid strategy and set of goals in mind. You can't simply take a leap of faith and draw conclusions. You must have both long and short term objectives, and you must put them into action.
  • Why create a simple and speedy registration process?– No one wants to spend more than a minute or two on a signup screen, especially if the app is intended for educational reasons. As a result, it's critical that the user registration, login, and signup procedure be simple and quick. It should provide one-tap or social login options so that the AI can read the social account and fill in the data on its own.
  • Why have a visually appealing homepage– "The first impression is the final impression" and "The last impression is the enduring impression" are two prominent expressions. When you initially open the app, the first thing that appears on your screen is the homepage, and if it isn't appealing enough, you will most likely not want to use it. As a result, the user interface must be simple to use and appealing to the eye.
  • Why do we alter and revise– Once you've begun creating the app, you can customise and revise it to meet the needs of your users, thanks to the Udemy Clone Script's high level of customization and a large range of templates and motifs to select from.


If you want to develop a platform with high-quality eLearning features that cater to the needs of a large mass of audience, then opt for ExpertPlus LMS, and contact BSEtec now! Hurry!

#Best Learning Management Software #Udemy Clone Script  #Best LMS App #Best LMS Platform #Best Open Source Web Conferencing System #Learning Management Portal #Learning Management Software
 

Carmen Grimes

Carmen Grimes

1595491178

Best Electric Bikes and Scooters for Rental Business or Campus Facility

The electric scooter revolution has caught on super-fast taking many cities across the globe by storm. eScooters, a renovated version of old-school scooters now turned into electric vehicles are an environmentally friendly solution to current on-demand commute problems. They work on engines, like cars, enabling short traveling distances without hassle. The result is that these groundbreaking electric machines can now provide faster transport for less — cheaper than Uber and faster than Metro.

Since they are durable, fast, easy to operate and maintain, and are more convenient to park compared to four-wheelers, the eScooters trend has and continues to spike interest as a promising growth area. Several companies and universities are increasingly setting up shop to provide eScooter services realizing a would-be profitable business model and a ready customer base that is university students or residents in need of faster and cheap travel going about their business in school, town, and other surrounding areas.

Electric Scooters Trends and Statistics

In many countries including the U.S., Canada, Mexico, U.K., Germany, France, China, Japan, India, Brazil and Mexico and more, a growing number of eScooter users both locals and tourists can now be seen effortlessly passing lines of drivers stuck in the endless and unmoving traffic.

A recent report by McKinsey revealed that the E-Scooter industry will be worth― $200 billion to $300 billion in the United States, $100 billion to $150 billion in Europe, and $30 billion to $50 billion in China in 2030. The e-Scooter revenue model will also spike and is projected to rise by more than 20% amounting to approximately $5 billion.

And, with a necessity to move people away from high carbon prints, traffic and congestion issues brought about by car-centric transport systems in cities, more and more city planners are developing more bike/scooter lanes and adopting zero-emission plans. This is the force behind the booming electric scooter market and the numbers will only go higher and higher.

Companies that have taken advantage of the growing eScooter trend develop an appthat allows them to provide efficient eScooter services. Such an app enables them to be able to locate bike pick-up and drop points through fully integrated google maps.

List of Best Electric Bikes for Rental Business or Campus Facility 2020:

It’s clear that e scooters will increasingly become more common and the e-scooter business model will continue to grab the attention of manufacturers, investors, entrepreneurs. All this should go ahead with a quest to know what are some of the best electric bikes in the market especially for anyone who would want to get started in the electric bikes/scooters rental business.

We have done a comprehensive list of the best electric bikes! Each bike has been reviewed in depth and includes a full list of specs and a photo.

Billy eBike

mobile-best-electric-bikes-scooters https://www.kickstarter.com/projects/enkicycles/billy-were-redefining-joyrides

To start us off is the Billy eBike, a powerful go-anywhere urban electric bike that’s specially designed to offer an exciting ride like no other whether you want to ride to the grocery store, cafe, work or school. The Billy eBike comes in 4 color options – Billy Blue, Polished aluminium, Artic white, and Stealth black.

Price: $2490

Available countries

Available in the USA, Europe, Asia, South Africa and Australia.This item ships from the USA. Buyers are therefore responsible for any taxes and/or customs duties incurred once it arrives in your country.

Features

  • Control – Ride with confidence with our ultra-wide BMX bars and a hyper-responsive twist throttle.
  • Stealth- Ride like a ninja with our Gates carbon drive that’s as smooth as butter and maintenance-free.
  • Drive – Ride further with our high torque fat bike motor, giving a better climbing performance.
  • Accelerate – Ride quicker with our 20-inch lightweight cutout rims for improved acceleration.
  • Customize – Ride your own way with 5 levels of power control. Each level determines power and speed.
  • Flickable – Ride harder with our BMX /MotoX inspired geometry and lightweight aluminum package

Specifications

  • Maximum speed: 20 mph (32 km/h)
  • Range per charge: 41 miles (66 km)
  • Maximum Power: 500W
  • Motor type: Fat Bike Motor: Bafang RM G060.500.DC
  • Load capacity: 300lbs (136kg)
  • Battery type: 13.6Ah Samsung lithium-ion,
  • Battery capacity: On/off-bike charging available
  • Weight: w/o batt. 48.5lbs (22kg), w/ batt. 54lbs (24.5kg)
  • Front Suspension: Fully adjustable air shock, preload/compression damping /lockout
  • Rear Suspension: spring, preload adjustment
  • Built-in GPS

Why Should You Buy This?

  • Riding fun and excitement
  • Better climbing ability and faster acceleration.
  • Ride with confidence
  • Billy folds for convenient storage and transportation.
  • Shorty levers connect to disc brakes ensuring you stop on a dime
  • belt drives are maintenance-free and clean (no oil or lubrication needed)

**Who Should Ride Billy? **

Both new and experienced riders

**Where to Buy? **Local distributors or ships from the USA.

Genze 200 series e-Bike

genze-best-electric-bikes-scooters https://www.genze.com/fleet/

Featuring a sleek and lightweight aluminum frame design, the 200-Series ebike takes your riding experience to greater heights. Available in both black and white this ebike comes with a connected app, which allows you to plan activities, map distances and routes while also allowing connections with fellow riders.

Price: $2099.00

Available countries

The Genze 200 series e-Bike is available at GenZe retail locations across the U.S or online via GenZe.com website. Customers from outside the US can ship the product while incurring the relevant charges.

Features

  • 2 Frame Options
  • 2 Sizes
  • Integrated/Removable Battery
  • Throttle and Pedal Assist Ride Modes
  • Integrated LCD Display
  • Connected App
  • 24 month warranty
  • GPS navigation
  • Bluetooth connectivity

Specifications

  • Maximum speed: 20 mph with throttle
  • Range per charge: 15-18 miles w/ throttle and 30-50 miles w/ pedal assist
  • Charging time: 3.5 hours
  • Motor type: Brushless Rear Hub Motor
  • Gears: Microshift Thumb Shifter
  • Battery type: Removable Samsung 36V, 9.6AH Li-Ion battery pack
  • Battery capacity: 36V and 350 Wh
  • Weight: 46 pounds
  • Derailleur: 8-speed Shimano
  • Brakes: Dual classic
  • Wheels: 26 x 20 inches
  • Frame: 16, and 18 inches
  • Operating Mode: Analog mode 5 levels of Pedal Assist Thrott­le Mode

Norco from eBikestore

norco-best-electric-bikes-scooters https://ebikestore.com/shop/norco-vlt-s2/

The Norco VLT S2 is a front suspension e-Bike with solid components alongside the reliable Bosch Performance Line Power systems that offer precise pedal assistance during any riding situation.

Price: $2,699.00

Available countries

This item is available via the various Norco bikes international distributors.

Features

  • VLT aluminum frame- for stiffness and wheel security.
  • Bosch e-bike system – for their reliability and performance.
  • E-bike components – for added durability.
  • Hydraulic disc brakes – offer riders more stopping power for safety and control at higher speeds.
  • Practical design features – to add convenience and versatility.

Specifications

  • Maximum speed: KMC X9 9spd
  • Motor type: Bosch Active Line
  • Gears: Shimano Altus RD-M2000, SGS, 9 Speed
  • Battery type: Power Pack 400
  • Battery capacity: 396Wh
  • Suspension: SR Suntour suspension fork
  • Frame: Norco VLT, Aluminum, 12x142mm TA Dropouts

Bodo EV

bodo-best-electric-bikes-scootershttp://www.bodoevs.com/bodoev/products_show.asp?product_id=13

Manufactured by Bodo Vehicle Group Limited, the Bodo EV is specially designed for strong power and extraordinary long service to facilitate super amazing rides. The Bodo Vehicle Company is a striking top in electric vehicles brand field in China and across the globe. Their Bodo EV will no doubt provide your riders with high-level riding satisfaction owing to its high-quality design, strength, breaking stability and speed.

Price: $799

Available countries

This item ships from China with buyers bearing the shipping costs and other variables prior to delivery.

Features

  • Reliable
  • Environment friendly
  • Comfortable riding
  • Fashionable
  • Economical
  • Durable – long service life
  • Braking stability
  • LED lighting technology

Specifications

  • Maximum speed: 45km/h
  • Range per charge: 50km per person
  • Charging time: 8 hours
  • Maximum Power: 3000W
  • Motor type: Brushless DC Motor
  • Load capacity: 100kg
  • Battery type: Lead-acid battery
  • Battery capacity: 60V 20AH
  • Weight: w/o battery 47kg

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AppClues Infotech

AppClues Infotech

1608989774

Hire Best Custom Software Developers in USA

Looking for the best custom software developers in the USA? Then AppClues Infotech recognized one of the best custom software development service providers by Digital.com that builds high-performance, secure & robust software applications for your business.

For more info:
Website: https://www.appcluesinfotech.com/
Email: info@appcluesinfotech.com
Call: +1-978-309-9910

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