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OPS435 Ansible

7,729 bytes added, 16:10, 24 November 2019
Lab 9 Sign-off (Show Instructor)
[[Category:OPS435]][[Category:rchan]][[Category:OPS435 Lab]]
= Objective =
:# Install and configure Ansible on a controller Linux machine
:# Explore Ansible's ad hoc commands
:# Explore Ansible's built-in modules
:# Explore and create Ansible playbooks
 
= Overview =
* [https://www.ansible.com/overview/how-ansible-works Overview]::"Ansible is an agentless IT automation engine that automates for automating cloud provisioning, configuration management, application deployment, intra-service orchestration, and many other IT needs.::Ansible was designed for multi-tier deployments since day one, and models your IT infrastructure by describing how all of your systems inter-relate, rather than just managing one system at a timeadministration tasks.::Ansible uses no agents and no additional custom security infrastructure, and it uses a very simple human readable language called 'YAML', to compose an Ansible Playbook which allow you to describe your automation jobs in a very simple waydescribes the tasks you want to automate."
= Reference =:* For more detail information about ansible, check out the ansible web site at [http://www.ansible.com. www.ansible.com]:* [https://www.ansible.com/overview/how-ansible-works Overview]:* [https://docs.ansible.com/ansible/latest/user_guide/index.html Ansible Latest User Guide]:* [https://proquest-safaribooksonline-com.libaccess.senecacollege.ca/book/operating-systems-and-server-administration/linux/9781785282300 Ansible Configuration Management] - Second Edition::* By: Daniel Hall, Publisher: Packt Publishing Pub. ::* Date: April 27, 2015,ISBN-13: 978-1-78528-230-0::* Pages in Print Edition: 122 = System requirements =* You must have at lease two networked machines** control machine - run ansible to configure remote node - need Ansible 2.x (latest version 2.7)** managed machine(s) - to be managed by the control node* You should be able to ssh from your control machine as a regular user to any of your remote machines as regular user without supplying a login password.* You account on the remote machine should be a sudoer and can run sudo without password.* You should also be to ssh from your control machine as a regular user to any of your remote machines as root without supplying a login password* Python 2.7+ on all nodes
= Objective =
* Install and configure Ansible on a controller Linux machine
* Explore Ansible's ad hoc commands
* Explore and create Ansible playbooks
* Access online documentation of Ansible's modules
= Investigation I: Introduction to Ansible =: In this introduction, we explore the main components of the Ansible configuration management system and its operating environment. we also study a simple playbook for managing the configuration of a CentOS 7.x VM. For : You need at least two VMs for this lab: one VM to be used as the control machine and one or more detail information about ansible, check out VMs to be used as the ansible web site at [https://wwwmanaged machines.ansible.com. https://www.ansibleYou only need to install Ansible on the control machine.com]
== Key Concepts when using Ansible==
* YAML - a human-readable data serialization language & is commonly used for configuration filesuse by Ansible's playbooks. To know more, your can check out the [https://en.wikipedia.org/wiki/YAML wikipedia page here]* Control machine - (Management node)* Remote machine - (managed node)* playbook - contains one or multiple plays, each of the host on which define the work you use Ansible to be done for a configuration execute tasks on a the managed server. Playbooks are written in YAML. Every play in the playbook is created with environment-specific parameters for the target machines; there are no standard plays.* Inventory file Managed machine - defines a host that is configured by the hosts and groups of hosts upon which commands, modules, and tasks in a playbook operate.control machine
* [[OPS435 Sample Ansible Hosts file|Hosts file]] - contains information about machines to be managed - click [[OPS435 Sample Ansible Hosts file | here]] for sample hosts file
* Ad hoc commands- a simple one-off task:
** <u><b>shell commands</b></u>
*** ansible 192.168.99.153 -a 'date'
*** ansible 192.168.99.153 -a 'df'
*** ansible 192.168.99.153 -a 'iptables -L -n -v' -u root
* Built-in modules - code that performs a particular task such as copy a file, installing a package, etc:
** <u><b>copy module</b></u>
*** ansible 192.169168.99.153 -m copy -a "src=/ops435/ansible.txt dest=/tmp/ansible.txt"
** <u><b>Package management</b></u>
*** ansible 192.168.99.153 -m yum -a "name=epel-release state=latest"
* Playbooks - contains one or multiple plays, each play defines a set of repeatable tasks on one or more managed machines. Playbooks are written in YAML. Every play in the playbook is created with environment-specific parameters for the target machines:
** ansible-playbook -i 192.168.99.153, setup_webserver.yaml
** ansible-playbook firstrun.yaml
== Hardware and software required
== Part 1: Installing Ansible on CentOS 7 ==
: You only need to install the "ansible" package on your control VM.
:* Login as a regular user, change to the directory ~/ops435/lab9
:* Issue the following command to install the "ansible" package: <source lang="bash">
sudo yum install ansible -y
</source>
 
:* You may have to install the following dependent packages:<source lang="bash">
Dependencies Resolved
 
=====================================================================================================================
Package Arch Version Repository Size
=====================================================================================================================
Installing:
ansible noarch 2.9.1-1.el7 epel 17 M
Installing for dependencies:
python-babel noarch 0.9.6-8.el7 base 1.4 M
python-cffi x86_64 1.6.0-5.el7 base 218 k
python-enum34 noarch 1.0.4-1.el7 base 52 k
python-httplib2 noarch 0.9.2-1.el7 extras 115 k
python-idna noarch 2.4-1.el7 base 94 k
python-jinja2 noarch 2.7.2-4.el7 base 519 k
python-markupsafe x86_64 0.11-10.el7 base 25 k
python-paramiko noarch 2.1.1-9.el7 base 269 k
python-ply noarch 3.4-11.el7 base 123 k
python-pycparser noarch 2.14-1.el7 base 104 k
python2-cryptography x86_64 1.7.2-2.el7 base 502 k
python2-jmespath noarch 0.9.0-3.el7 extras 39 k
python2-pyasn1 noarch 0.1.9-7.el7 base 100 k
sshpass x86_64 1.06-2.el7 extras 21 k
 
Transaction Summary
=====================================================================================================================
Install 1 Package (+14 Dependent packages)
 
Total download size: 21 M
Installed size: 120 M
Is this ok [y/d/N]:
</source>
 
: To confirm that you have Ansible installed, try the following command:<source lang="python">
[rchan@c7-rchan ~]$ ansible --help
usage: ansible [-h] [--version] [-v] [-b] [--become-method BECOME_METHOD]
[--become-user BECOME_USER] [-K] [-i INVENTORY] [--list-hosts]
[-l SUBSET] [-P POLL_INTERVAL] [-B SECONDS] [-o] [-t TREE] [-k]
[--private-key PRIVATE_KEY_FILE] [-u REMOTE_USER]
[-c CONNECTION] [-T TIMEOUT]
[--ssh-common-args SSH_COMMON_ARGS]
[--sftp-extra-args SFTP_EXTRA_ARGS]
[--scp-extra-args SCP_EXTRA_ARGS]
[--ssh-extra-args SSH_EXTRA_ARGS] [-C] [--syntax-check] [-D]
[-e EXTRA_VARS] [--vault-id VAULT_IDS]
[--ask-vault-pass | --vault-password-file VAULT_PASSWORD_FILES]
[-f FORKS] [-M MODULE_PATH] [--playbook-dir BASEDIR]
[-a MODULE_ARGS] [-m MODULE_NAME]
pattern
...
</source>
: Take a look of all the available command line options for the "ansible" command. There are a lots of options when running Ansible. Let's move on to try a few simple ones.
== Part 2: Sample runs for some of the Ad hoc commands ==
<pre>
[rchan@centos7 ansible]$ ansible 192.168.99.153 -m copy -a "src=/home/rchan/ops435/ansible/ansible.txt dest=/tmp/ansible.txt"
"uid": 1001
}
</pre>
: 192.168.99.153 is the remote machine's IP address.
: "-m copy" tells ansible to use the copy module
: after '-a' is the arguments to the copy module, which specify the source file and the destination for the copy action.
: If you got the same "SUCCESS" message, login to the remote machine (in this example, it is 192.168.99.153) and check the directory "/tmp" for the file ansible.txt.
 
== Part 3: Sample runs for using some Ansible's built-in modules ==
: "yum" is a built-in ansible module. You can get a complete list of all the ansible modules installed on you system with the following command:<source lang="bash">
ansisble-doc --list_files
</source>
: You can also get the detail information about any ansible module with the following command:<source lang="bash">
ansible-doc module_name
 
e.g. ansible_doc yum
</source>
: The following command demonstrates how to install the "epel-release" package with the "yum" module:
<pre>
[rchan@centos7 ansible]$ ansible 192.168.99.153 -m yum -a "name=epel-release state=present"
192.168.99.153 | SUCCESS => {
]
}
 
[rchan@centos7 ansible]$ ansible 192.168.99.153 -m yum -a "name=epel-release state=present" -u root
192.168.99.153 | SUCCESS => {
]
}
 
[rchan@centos7 ansible]$ ansible 192.168.99.153 -m yum -a "name=epel-release state=latest" -u root
192.168.99.153 | SUCCESS => {
</pre>
== Part 4: Gather all the software and hardware information available on remote machine ==: One of the main ansible module is called "setup", it is automatically called by ansible playbook to gather useful "facts" about remote hosts that can be used in ansible playbooks. It can also be executed directly by the ansible command (/usr/bin/ansible) to check what "facts" are available to a host.
<pre>
[rchan@centos7 ansible]$ ansible 192.168.99.153 -m setup
[[OPS435_Ansible_setup|Click here for complete contents of the above]]
= Investigation II: Ansible Playbook === Updating What is a playbook? ==: * Playbook is one of the core features of Ansible.: * Playbook tells Ansible what to execute by which user on the remote machine.: * Playbook is like a to-do list for Ansible: * Playbook is written "YAML".: * Playbook links a task to an ansible module and provide needed arguments to the module which requires them. ==Part 1: A playbook to update the /etc/motd file ==
Name: motd-play.yml
<pre>
</pre>
== Install Part 2: A playbook to install and start Apache Server ==
Name: httpd-play.yml
<pre>
</pre>
= Investigation III: Using Playbook to config a OPS435 Linux machine =
: You have just installed the latest version of CentOS 7.x on a VM with GNOME Desktop. You need to configure it so that you can use it for doing the Labs for OPS435. The following configuration need to be done on that VM:
:* update all the packages installed on the VM
:* install extra packages repository for enterprise Linux
:* install python3 if it is not already installed
:* set the host name to your Seneca user name
:* install the git package
:* create a new user with your Seneca_id with sudo access
:* configure the new user account so that you can ssh to it without password
:* setup a directory structs for completing and organizing labs as shown below:<source lang="bash">
/home/[seneca_id]/ops435/lab0
/home/[seneca_id]/ops435/lab1
/home/[seneca_id]/ops435/lab2
/home/[seneca_id]/ops435/lab3
/home/[seneca_id]/ops435/lab4
/home/[seneca_id]/ops435/lab5
/home/[seneca_id]/ops435/lab6
/home/[seneca_id]/ops435/lab7
/home/[seneca_id]/ops435/lab8
/home/[seneca_id]/ops435/lab9
</source>
:* create a playbook named "config_ops435.yml" to perform the tasks mentioned above.
:* test your playbook and capture its output when it complete without error.
= Questions Lab 9 Sign-off (Show Instructor) == System requirements = Have the following items ready to show your instructor: ==: * You must have at lease two networked machines** control node - run ansible to configure remote node - need The Ansible 2playbook called "config_ops435.x (latest version 2yml" for configuring the VM mentioned in Lab 1.7): ** remote nodes - to be managed by The result of running the playbook "config_ops435.yml". Save the control node* You should be to ssh from your control node as result in a regular user to any of your remote nodes as root user without supplying a login passwordfile called "lab9_[seneca_id].txt"* Python 2.7+ on all nodes= Reference = Upload the following files to blackboard ==: * [https://proquest-safaribooksonline-com.libaccess.senecacollege.ca/book/operating-systems-and-server-administration/linux/9781785282300 Ansible Configuration Management] - Second Edition By: Daniel Hall, Publisher: Packt Publishing Pubconfig_ops435. Date: April 27, 2015,ISBN-13: 978-1-78528-230-0yml Pages in Print Edition: 122* lab9_[https://docsseneca_id].ansible.com/ansible/latest/user_guide/index.html Ansible Latest User Guide]txt
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