DevOps Archives - Page 85 of 91 - DEVOPS DONE RIGHT.

The Reset Button !!!!

!!!! The Reset button !!!!

Anyone who has recently used the Google Compute Engine for creating the VM instances will be aware of the reset button available.

Since I wasn’t very much sure of it , I just clicked it without much know-how . This resulted in making all the servers to their original state as they were freshly build and which is certainly a very bad thing for us.

But , we had puppet that we used to create the whole infrastructure as it is . All the modules we had used and changes we made were committed to GitHub repo and this certainly was a boon to us, else we have to sit whole day long for making those changes on the servers.

Just in couple of minutes the new instances were created using the compute engine-create group instance feature. We did installation of the foreman and git on one of the servers and set up the puppet clients agents accordingly . This took around 15 more crucial minutes and then cloned our GitHub repo which contains all the necessary modules and configurations required for the rest of infrastructure.

These are the conditions where Configuration Management Tools like Puppet come in picture and help us get on the track in the shortest possible manner.
It was a hectic day but definitely made us learn several important aspects. Using puppet for maintain the infrastructure is really important now days. It is reliable,efficient and fast for deploying configurations on the servers and making ready for the production work load.

Setup Jenkins using Ansible

In this document I’ll walk you through how you can setup Jenkins using Ansible.

Prerequisites

OS – Ubuntu {at least two machine required in production}
First machine for Ansible installation
Second machine where we will install jenkins server
You should have basic understanding of ansible workflow.

Note : You should have password less login enabled in second machine. use this link
http://www.linuxproblem.org/art_9.html

Ansible Installation
Before starting with installing Jenkins using Ansible, you need to have Ansible installed in your system.

$ curl https://raw.githubusercontent.com/OpsTree/AnsiblePOC/alok/scripts/Setup/setup_ansible.sh | sudo bash

Setup jenkins using Ansible
Install jenkins ansible roles
Once we have ansible installed in our system, we can start installing the jenkins using ansible. To install we will use an already available ansible role to setup jenkins

$ ansible-galaxy install geerlingguy.jenkins

to know more about the jenkins role hit this link https://galaxy.ansible.com/detail#/role/440

Ansible roles default directory path is /etc/ansible/roles
Make ansible playbook file

Now the next step is to use the installed jenkins roles to install the jenkins. For this purpose we will create a playbook and hosts file with below content

$ cd ~/MyPlaybook/jenkins

create a file hosts and add below content

[jenkins_hosts]

192.168.33.15

Next create a file site.yml and add below content

—

– hosts: jenkins_hosts

roles:

– { role: geerlingguy.jenkins }

so configuration file is done, the next step is to run ansible playbook command

$ ansible-playbook -i hosts site.yml

Now that Jenkins is running, go to http://192.168.33.15:8080. You’ll be welcome by the default Jenkins screen.

Opstree SHOA Part 1: Build & Release

At Opstree we have started a new initiative called SHOA, Saturday Hands On Activity. Under this program we pick up a concept, tool or technology and do a hands on activity. At the end of the day whatever we do is followed by a blog or series of blog that we have understood during the day.

Since this is the first Hands On Activity so we are starting with Build & Release.

What we intend to do

Setup Build & Release for project under git repository https://github.com/OpsTree/ContinuousIntegration.

What all we will be doing to achieve it

Finalize a SCM tool that we are going to use puppet/chef/ansible.
Automated setup of Jenkins using SCM tool.
Automated setup of Nexus/Artifactory/Archiva using SCM tool.
Automated setup of Sonar using SCM tool.
Dev Environment setup using SCM tool: Since this is a web app project so our Devw443 environment will have Nginx & tomcat.
QA Environment setup using SCM tool: Since this is a web app project so our QA environment will have Nginx & tomcat.
Creation of various build jobs
- Code Stability Job.
- Code Quality Job.
- Code Coverage Job.
- Functional Test Job on dev environment.
Creation of release Job.
Creation of deployment job to do deployment on Dev & QA environment.

This activity is open for public as well so if you have any suggestion or you want to attend it you are most welcome

Marrying Nginx with ELB

Few weeks back I got a requirement to setup a highly available API server. I said not a big deal! I’ll have Nginx as a reverse proxy(Why not directly exposing API via ELB a different story) and my API auto scaled setup will sit behind an internal ELB and things would be in place TA DA.

Things worked perfectly fine for few days, but one day the API consumer reported that they are not getting response back, what? When I checked the API url was indeed returning a 502 error code. It was really strange for nginx to be sending 502 response back that meant the highly scalable setup was down? Well I was proven wrong ELB was working perfectly fine as the curl request to internal ELB was returning proper response, so yes the highly available API setup was in place. What next, yes! Nginx error logs. I did saw Nginx reporting connection timeout with 502 error code. The interesting thing to note that it was an IP(random IP assigned to ELB), when I tried to do curl hit on that IP for API request, it did failed EUREKA EUREKA!! I reproduced the problem.

Well now I’ve to collect all this information and infer what is the logical cause of the problem, and yes there are lot of smart people available who would have fond the solution to this problem so I’ve to ask right question in Google :). The question was “Nginx using Ip instead of domain name” and the answer was “Nginx caches the IP at the startup and obviously as ELB is Elastic in nature so it’s IP changes over the period of time”. That was the reason Nginx was trying to talk to the older un-associated IP’s of Internal ELB.

Finding solution was not a big task as it was just about making sure Nginx should talk to ELB not the IP’s associated with it, that’s why said marrying nginx with ELB :).

I’ll not go into the actual solution as there are already solutions available in web. I referred this really good blog as a solution.

http://ghost.thekindof.me/nginx-aws-elb-dns-resolution-nginx-resolver-directive-and-black-magic/

PERCONA STANDALONE SERVER

As a DevOps activist I am exploring Percona XtraDB. In a series of blogs I will share my learnings. This blog intends to capture step by step details of installation of Percona XtraDB in Standalone mode

Introduction:

Percona Server is an enhanced drop-in replacement for Mysql. It offers breakthrough performance, scalability, features, and instrumentation.

Percona focus on providing a solution for the most demanding applications, empowering users to get the best performance and lowest downtime possible.

The Percona XtraDB Storage Engine:

Percona XtraDB is an enhanced version of the InnoDB storage engine, designed to better scale on modern hardware, and including a variety of other features useful in high performance environments. It is fully backwards compatible, and so can be used as a drop-in replacement for standard InnoDB.
Percona XtraDB includes all of InnoDB’s robust, reliable ACID-compliant design and advanced MVCC architecture, and builds on that solid foundation with more features, more tunability. more metrics, and more scalability.
It is designed to scale better on many cores, to use memory more efficiently, and to be more convenient and useful.

Installation on ubuntu:

STEP 1: Add Percona Software Repositories

$ apt-key adv --keyserver keys.gnupg.net --recv-keys 1C4CBDCDCD2EFD2A

STEP 2: Add this to /etc/apt/sources.list:

deb http://repo.percona.com/apt precise main
deb-src http://repo.percona.com/apt precise main

STEP 3: Update the local cache

$ apt-get update

STEP 4: Install the server and client packages

$ apt-get install percona-server-server-5.6 percona-server-client-5.6

STEP 5: Start Percona Server

$ service mysql start

Let me know if you have any suggestions.