session9sl.txt

#create 3 ec2 amazon linux vm  , 1 Master and 2 Worker Nodes and install ansible
#connect to the servers
#switch to root
#update serverpackages
yum update -y

#5. Install the ansible 

It we install Ansible we need to follow below pre-requisites.

#Download epel repository.

wget https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

#Verify epel repository

ls

#Install epel repository.
yum install epel-release-latest-7.noarch.rpm

#Update epel repository.
yum update -y

#Install all individual packages inside the repository.
yum install git python python-devel python-pip openssl ansible -y


#Chek the Ansible version
ansible --version

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

#create a group add the private ip of the nodes run in master only
vi /etc/ansible/hosts

[demo]
<privateip node1>
<privateip node2>

:wq to save

#create a demo group run in master only
[demo]
<privateipnode1>
<privateipnode2>
:wq


#only in master
vi /etc/ansible/ansible.cfg

Remove # from inventory
Remove # from sudo su  or sudo_user = root

esc :wq
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#create user in master and nodes
adduser ansible
#set password
passwd ansible

#login to the created user
su - ansible

####add ansible to the sudoers file
#switch to ansible user
su - ansible
#can this user create a file
#can this user download the s/w

#come out of ansible and move to root
exit

#sudoers file should be edited to add the users to give the user root similar access

visudo : it will let us enter sudoers file or vi /etc/sudoers

#add the user and come to bottam 
<user> ALL=(ALL) NOPASSWD:ALL
esc :wq
 
#now try to download a s/w
 
sudo yum install httpd -y 
 
#same process should be done for node1 and node2

#try to ssh node1/node2 from ansible user. you will get permission denied
ssh <privateip>

######provide permission in both master and nodes
#move to root
exit
vi /etc/ssh/sshd_config

remove # uncomment
PermitRootLogin yes
PasswordAuthentication yes

put # before comment out
PasswordAuthentication no

# restart the sshd servce
service sshd restart

#try to ssh node user <user>
ssh <node private ip>
create file it will show
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
# create a ssh key at master and copy the same to nodes to do passwordless authentication

#Generate the Key in the master node
#generate without passphrase
ssh-keygen

#check if key got generated
cd ~/.ssh/

#copy the key to node server
ssh-copy-id user@privateip
[ansible@ip-172-31-57-116 .ssh]$ ssh-copy-id ansible@172.31.61.0

#Try to ssh now without password from ansible user , it will not work with other user
ssh <private-ip>

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#List The all hosts adhoc command
ansible all --list-hosts
ansible demo --list-hosts

ansible demo[1] --list-hosts

#if you  wanted to get last node of the group
ansible demo[-1] --list-hosts

#if you  wanted to get last node of the all the groups 
[root@ip-172-31-57-116 ~]# ansible all[-1] --list-hosts

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
what is adhoc command
what is module
what is playbook

++++++++++++++++++++++++ Exercise with Adhoc+++++++++++++++++++++++++++++++++
#usecase 1 , I will create manually files in nodes ansible users , I want list them using adhoc ansible command from the master
ansible <groupname> -a"linux command"  -----> -a stands for arguments

ansible demo -a"ls"

#usecase 2 , If i want to list the files in node1
ansible demo[1] -a"ls"

#usecase 3 install httpd in nodes in nodes
ansible demo -a"yum install httpd -y"
ansible demo -a"sudo yum install httpd -y"

ansible demo -a"sudo yum remove httpd -y"

#create a file in nodes 
ansible demo -a"touch niladri"

#create a directory in node1
ansible demo[1] -a"mkdir nil"


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#install docker using playbok #you need to understand 
[ansible@ip-172-31-57-116 ~]$ vi myfirstplaybook.yaml

--- #our first playbook to install the docker
- hosts: demo
  user: ansible
  become: yes
  connection: ssh
  tasks:
    - name: install docker on nodes
      action: yum name=docker state=present
	  

[ansible@ip-172-31-57-116 ~]$ ansible-playbook myfirstplaybook.yaml


+++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#Remove docker and install httpd using playbok #you need to understand
[ansible@ip-172-31-57-116 ~]$ cat myfirstplaybook.yaml
--- #our first playbook to install the docker
- hosts: demo
  user: ansible
  become: yes
  connection: ssh
  tasks:
    - name: install docker on nodes
      action: yum name=docker state=absent
    - name: install httpd
      action: yum name=httpd state=present
[ansible@ip-172-31-57-116 ~]$
+++++++++++++++++++++++++++++++++++++++++

#create a file in master and copy the same to node using play book

touch index.html

[ansible@ip-172-31-57-116 ~]$ cat myfirstplaybook.yaml
--- #our first playbook to install the docker
- hosts: demo
  user: ansible
  become: yes
  connection: ssh
  tasks:
    - name: install docker on nodes
      action: yum name=docker state=absent
    - name: install httpd
      action: yum name=httpd state=present
    - name: copy index.html
      ansible.builtin.copy:
           src: /home/ansible/index.html
           dest: /home/ansible/
[ansible@ip-172-31-57-116 ~]$


[ansible@ip-172-31-57-116 ~]$ cat myfirstplaybook.yaml
--- #our first playbook to install the docker
- hosts: demo
  user: ansible
  become: yes
  connection: ssh
  tasks:
    - name: install docker on nodes
      action: yum name=docker state=absent
    - name: install httpd
      action: yum name=httpd state=present
    - name: copy index.html
      ansible.builtin.copy:
           src: /home/ansible/index.html
           dest: /home/ansible/
    - name: create directory
      action: file name=niladridir state=directory
[ansible@ip-172-31-57-116 ~]$
+++++++++++++++++++++++++++++++
####run a module, using a module install docker

ansiable demo -b -m yum -a "pkg=docker state=present"

++++++++++++++++++++++++++++++++++++++++++
#host an application on the httpd server using handlers

[ansible@ip-172-31-57-116 ~]$ cat httpdserver.yaml
--- #Myweb For handlers
- hosts: demo #your host
  user: ansible #user
  become: yes #if you want to use root priviledge to perform some actions
  connection: ssh #connect type
  tasks:
    - name: install httpd
      action: yum name=httpd state=present
      notify: restart httpd
    - name: copy index.html
      ansible.builtin.copy:
           src: /home/ansible/index.html
           dest: /var/www/html/
  handlers:
    - name: restart httpd
      action: service name=httpd state=restarted
[ansible@ip-172-31-57-116 ~]$

+++++++++++++++++++++++++++++++
Simplilearn script
ansible -m shell -a "service apache2 status" webservers

ansible -m setup webservers 

ansible webservers -m shell -a 'hostname'

ansible webservers -m apt -a 'name=git state=present' --become

ansible webservers -m file -a 'dest=/root/sample.txt state=touch mode=600 owner=root group=root' --become


+++++++++++++++++++++++++++++++++++++++++

mkdir terraformsw

wget https://releases.hashicorp.com/terraform/0.14.9/terraform_0.14.9_linux_amd64.zip

unzip terraform_0.14.9_linux_amd64.zip

mv terraform /usr/local/bin/

terraform --version

++++++++++++++++++++++++++++++++
sudo yum install -y yum-utils
sudo yum-config-manager --add-repo https://rpm.releases.hashicorp.com/RHEL/hashicorp.repo
sudo yum -y install terraform
++++++++++++++++++++++++++++++++++++
++++++++++++++++++++

mkdir s3back
cd s3back

nano creds.tf


provider "aws" {
  access_key = ""
  secret_key = ""
  token = ""
  region = "us-east-1"
}


#
nano main.tf

resource "aws_s3_bucket" "b" {
  bucket = "niladri-test-bucket-1234"
  acl    = "private"

  tags = {
    Name        = "My bucket"
    Environment = "Dev"
  }
}


terraform init

terraform plan

terraform apply
+++++++++++++++++++++++++++++++