Added information on ansible configurtion file

Author: faizan

ansible-guide/README.md

@@ -27,3 +27,4 @@ Head over to [YAML-Tutorial](https://learnxinyminutes.com/docs/yaml/)
 ### Start Ansible
 
 - [Ansible-command](/ansible-guide/docs/doc-1.md)
+- [Ansible-configuration](/ansible-guide/docs/doc-2.md)

ansible-guide/docs/doc-2.md

@@ -0,0 +1,55 @@
+### Ansible configuration
+
+We can configure Ansible using different methods. Convention is use ```ansible.cfg``` as the file name. Order of configuration parsing
+
+```shell
+- export ANSIBLE_CONFIG=/path/to/ansible.cfg # Environment variable
+- ansible.cfg # In the current directory
+- .ansible.cfg # In ~/. ( home ) directory
+- /etc/ansible/ansible.cfg
+```
+
+Sample configuration file
+
+```shell
+[defaults]
+remote_user=ec2-user  # User which has ssh permission on target machines
+host_key_checking = False # This way you don't get prompted for accepting host key. This however could have security implications. Please read documentation
+inventory = /Users/my-generic-user/my-work/ansible-code/hosts/ # Location of inventory file
+# Enabling pipelining reduces the number of SSH operations required to
+# execute a module on the remote server. This can result in a significant
+# performance improvement when enabled, however when using "sudo:" you must
+# first disable 'require-tty' in /etc/sudoers
+pipelining = True
+timeout = 25
+retry_files_enabled = False
+connect_timeout = 30
+connect_retries = 30
+
+# Below settings are relevant for cases where you have a private/public network and ansible is to be executed from a specific machine in public subnet with restrictive permissions
+[ssh_connection]
+ssh_args = -F /Users/my-generic-user/my-work/ansible-code/ssh.cfg -o UserKnownHostsFile=/dev/null
+control_path = ~/.ssh/ansible-%%r@%%h:%%p
+private_key_file = /Users/my-generic-user/.ssh/myprivate-keys.pem
+
+```
+
+
+[Ansible-config-document](http://docs.ansible.com/ansible/latest/intro_configuration.html)
+
+
+### Exercise
+
+- Setup ansible.cfg
+- Find uptime of the target machine using ansible command ( ) # Hint: Use [command](http://docs.ansible.com/ansible/latest/command_module.html) module
+- Tail /var/log/syslog # Hint: You may have to use elevated privileges to do this
+- Install apache or nginx using ansible command. # Hint: Use [apt](http://docs.ansible.com/ansible/latest/apt_module.html) module
+
+#### NOTE:
+
+- Modules are the ones that do the actual work in ansible. They are like pluggable components that allow you perform actions on target hosts. Example modules
+ - command
+ - ping
+ - apt
+ - yum
+ and many more