- IaC is used to speed up the process of configuration management or orchestration
- Infrastructure automation tool for configuration management
- Connects via ssh
Ansible doesn’t use agents, and its code is written in YAML in the form of Ansible Playbooks, so configurations are very easy to understand and deploy.
- simple
- Agentless
- IT automation
- create 3 instances
- One Ansible controller instance - that will dictate the configuration of the two other instances in our network The controller virtual machine is the vm that has Ansible installed on it and the other instances do not require Ansible to be downloaded on them (Agentless)
Ubuntu 16.04 vm - webApp Ubuntu 16.04 vm - db
we want to install ansible on the aws virtual machine we have created using the vagrantfile look at the system of ansible how to create host entries tell the controller which ips to communicate with
- ssh into aws virtual machine
- sudo apt-get install software-properties-common -y
- sudo apt-get update sudo apt-get install software-properties-common sudo apt-add-repository ppa:ansible/ansible sudo apt-get update sudo apt-get install ansible sudo apt-get install tree
cd etc/ansible - default location for files
ansible "name of vm" -m ping - code to communicate to other vms
192.168.33.10 - web 192/168.33.11 - db
[web] 192.168.33.10 ansible_connection=ssh ansible_ssh_user=vagrant ansible_ssh_pass=vagrant [db] 192.168.33.11 ansible_connection=ssh ansible_ssh_user=vagrant ansible_ssh_pass=vagrant [aws] 192.168.33.12 ansible_connection=ssh ansible_ssh_user=vagrant ansible_ssh_pass=vagrant
this how we connect the controller to the vms
to ssh into the vms ssh vagrant@192.168.33.10
ping machines with ansible command
- First run the following up to run all the machines
vagrant up
- Enter each VM update the packages:
vagrant ssh db sudo apt-get update exit
vagrant ssh app vagrant ssh aws
- Enter the AWS and run this
sudo apt-get install software-properties-common -y sudo apt-add-repository ppa:ansible/ansible sudo apt-get install ansible -y # install ansible sudo apt-get install tree
- Enter /etc/ansible folder
cd /etc/ansible tree
- test no connected to app and
ping 192.168.33.11 ping 192.168.33.10 # testing connection with Db and app
- Create Host entries
cd ../../etc/ansible sudo nano hosts
[web] 192.168.33.10 ansible_connection=ssh ansible_ssh_user=vagrant ansible_ssh_pass=vagrant
[db] 192.168.33.11 ansible_connection=ssh ansible_ssh_user=vagrant ansible_ssh_pass=vagrant
- vagrant ssh into the other vm
ssh vagrant@192.168.33.10 ssh vagrant@192.168.33.11
sudo apt-get update
- ping the connections back in aws controller
ansible all -m ping
ad hoc commads are one line commands that provide the functionality of ansible An Ansible ad-hoc command uses the /usr/bin/ansible command-line tool to automate a single task on one or more managed nodes. Ad-hoc commands are quick and easy, but they are not reusable
ad hoc commands - easy to use and gives a lot of information about a particular virtual machine. we can gather this information by gathering from the controller as oppose to the ssh'ing in to the vm itself
ansible web -a "date"
ansible db -a "uname -a"
ansible all -m shell -a "ls -a"
ansible all -a "free"
ansible atlanta -m copy -a "src=/etc/hosts dest=/tmp/hosts"
ansible all -m shell -a 'echo hello world'
ansible webservers -m file -a "dest=/srv/foo/a.txt mode=600"
ansible all -m shell -a "hostname -I" - returns ip address of vm
ansible all -m shell -a "ifconfig" - returns all ip addresses of vm
ansible all -m shell -a "uptime" - uptime of instances
ansible all -m shell -a "env" - environment variables of instances
ansible all -m shell -a "free" - returns free space of instances
Playbooks are Ansible’s configuration, deployment, and orchestration language. written in YAML file ext is .yml or .yaml (yet another markup language)
YAML file start with three dashes (---) Kubernetes uses YAML Docker compose uses YAML widely used within the realm of infrastructure as code
we create the playbook within the Controller instances (the vm with ansible installed)
the playbook operates just like a bash script but has more powerful functionality automates the tasks we need to carry out in multiple locations
command to run playbook: n