Ansible Modules, File Module, Copy Module, Fetch Module, Git Module, Service Module, Replace Module, Performing Related Operations Using Multiple Module Creating a Playbook and running it.

File module

This is used to create files and folder on managed nodes

ansible all -m file -a ‘name=/tmp/file5 state=touch’

To check the file which is create
$ ssh 172.31.3.15
$ cd /tmp
$ ls
$ exit

TO create a directory
ansible all -m file -a ‘name=/tmp/dir1 state=directory’

To check the directory
$ ssh 172.31.39.33
$ cd /tmp
$ ls
$ exit

To delete the file
ansible all -m file -a ‘name=/tmp/file5 state=absent’

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Notes:
Command to create a file on all managed nodes

ansible all -m file -a ‘name=/tmp/file1 state=touch’

state=touch is to create files
state=directory is to create directory
state=absent is for deleting file/directory

++++++++++++++++++++
Now,
To know the current user
$ whoami
$ ansible all -m file -a ‘name=file1 state=touch’

Now go to managed nodes and check the permission of the file
$ ssh 172.31.10.15
$ ls -l file1

Observe the permissions are rw-rw-r–

Now, I want to change the permissions from controller
$ exit ( will come back to controller )

$ ansible all -m file -a ‘name=file1 state=touch owner=Anu group=Ravi mode=700’ -b

The above command will execute only if Anu user and Ravi group is available in all nodes.

Notes:
File module can be used to change the ownership, group ownership and permissions on the file.

Copy Module

This is used for copying the files from controller into managed nodes.

We know in the file /etc/passwd we have all the information about users

Now I want to copy the file into all nodes

$ ansible all -m copy -a ‘src=/etc/passwd dest=/tmp’

To check the file which is copies

$ ssh 172.31.12.239
$ cd /tmp
$ ls
$ exit

++++++++++++++
Scenario:
I want to create tomcat users file in controller and copy the file in all the nodes

$ sudo vim tomcat-users.xml

Go to Insert mode

:wq

$ ansible all -m copy -a ‘src=tomcat-users.xml dest=/etc/tomcat8’ -b

To check the file

$ ssh 172.31.12.239
$ cd /etc/tomcat8
$ ls
Open that file to check the contents

$ sudo cat tomcat-users.xml

+++++++++++++++++++++++++++++++
Ansible command to copy /etc/passwd file to all the managed nodes
$ ansible all -m copy -a ‘src=/etc/passwd dest=/tmp’

+++++++++++++++++++++
Create a tomcat-users.xml file on controller and copy it into all managed nodes into default location of tomcat ie /etc/tomcat8

$ sudo vim tomcat-users.xml

Go to Insert mode




:wq

$ ansible all -m copy -a ‘src=tomcat-users.xml dest=/etc/tomcat8’ -b

++++++++++++++++++++++++++++++++++++
Create a file on the controller machine

$ cat > newfile1
aaaa
bbbbb
ccccc
ddddd
Ctrl+d

$ ls -l newfile1
we get the permissions
rw-rw-r–
When we copy the file we have the same permissions

$ ansible all -m copy -a ‘src=newfile1 dest=/home/ubuntu’

To got managed node and check the permissions on the file. It remains the same

$ ssh 172.31.10.15
$ ls -l newfile1
$ exit

Command to copy with changes permissions

$ ansible all -m copy -a ‘src=newfile1 dest=/home/ubuntu owner=root group=root mode=760’ -b

Now, go to node and check the permissions

$ ssh 172.31.10.15
$ ls -l newfile1
$ exit

Notes:
Copy module is used to change the ownership, group ownership and permissions of the files that are copied to managed nodes.

$ ansible all -m copy -a ‘src=newfile1 dest=/home/ubuntu owner=root group=root mode=760’ -b

+++++++++++++++++++++++++++++++++++++
To copy the file , by replacing the old content with new content
$ ansible all -m copy -a ‘content=”sunil\n” dest=newfile1’ -b

$ ansible all -m copy -a ‘content=”Anuj\n” dest=newfile1’ -b

TO to managed node and check the content

$ ssh 172.31.10.15
$ sudo cat newfile1
$ exit

Notes: Copy module can also send content into the file
$ ansible all -m copy -a ‘content=”sunil\n” dest=newfile1’ -b

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

Fetch Module ( opposite of copy module )

Go to managed node

$ ssh 172-31-35-79
$ cd /etc/tomcat8
$ ls

There is server.xml file
I want to get the file ( server.xml) from node to controller

$ exit ( come back to controller )
$ ansible all -m fetch -a ‘src=/etc/tomcat8/server.xml dest=/tmp’ -b

Now to got tmp folder

$ cd /tmp
$ ls

You will find three folders. The names of the folers are IP address of managed nodes

$ cd 172.31.35.102
$ ls
$ cd etc
$ ls
$ cd tomcat8
$ ls

Notes:
Fetch module is used to copy files from managed nodes to controller.
Command to copy tomcat-server.xml file from all managed nodes into /tmp folder on the controller.

$ ansible all -m fetch -a ‘src=/etc/tomcat8/server.xml dest=/tmp’ -b

Git Modules

This is used to perform git version controlling on the managed nodes.

ansible all -m git -a ‘repo=https://github.com/sunildevops77/repo1.git dest=/tmp/mygit’ -b

The above command will download the files in all managed nodes.

Go to managed node and check
$ ssh 172.31.35.79
$ cd /tmp
$ ls
$ cd mygit
$ ls
$ exit

Notes:
Ansible command to clone remote git repository into all managed nodes
ansible all -m git -a ‘repo=https://github.com/sunildevops77/rep1.git dest=/tmp/mygit’ -b

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

Service Module

This is used for starting/ stoping / restarting the services.

Ansible command to restart tomcat8 on all managed nodes
$ ansible all -m service -a ‘name=tomcat8 state=restarted’ -b

state=restarted is for restarting a service
state=stopped is for stopping a running service
state=started is for starting a stopped service

Replace module

Go to managed node
$ ssh 172.31.36.52
$ cd /etc/tomcat8/
$ ls
$ sudo vim server.xml

Look for connector port , to see the port number in which it is running. ( line 74)

Now, we want to change the port number on all managed nodes, in this scenario
we use replace module.

Quit the server.xml file

$ exit ( to come back to controller )
$ ansible all -m replace -a ‘regexp=8080 replace=9090 path=/etc/tomcat8/server.xml’ -b

Lets check tomcat is respoding on 9090 port in managed node

Get public DNS from aws
ec2-13-251-114-207.ap-southeast-1.compute.amazonaws.com
ec2-13-234-48-168.ap-south-1.compute.amazonaws.com

Open Browser
URL — ec2-13-251-114-207.ap-southeast-1.compute.amazonaws.com:9090

We will not get the page, becuase we need to restart the service

$ ansible all -m service -a ‘name=tomcat8 state=restarted’ -b

Now, try the above URL — it Works!!

replace module

This is used for replacing a specific string with other string.
Ex:
Ansible command to change the port number of tomcat from 8080 to 9090
$ ansible all -m replace -a ‘regexp=8080 replace=9090 path=/etc/tomcat8/server.xml’ -b

uri module

I want to check facebook is reachable for not in all managed nodes.

$ ansible all -m uri -a ‘url=http://facebook.com’

In the output ( green color ) status – 200

Give a invalid url , we get status as -1
Ex:
$ ansible all -m uri -a ‘url=http://hgyi9cb.com’

Now, I want to stop tomcat in all managed nodes ( Just repeat )
$ ansible all -m service -a ‘name=tomcat8 state=stopped’ -b

Notes:
urI module is used to check if the url is reachable or not.
Command to check if facebook.com is reachable on all managed nodes.
$ ansible all -m uri -a ‘url=http://facebook.com status=200’

++++++++++++++++++++++++++++++++++++
Lets have an example of all modules
Requirement: I want to install tomcat all manages nodes , then i want to copy users.xml in all managed nodes,
I want to change port number of tomcat , then i want to restart the service, finally i want to check
url is reachable or not.

1st we need to unintall tomcat in all managed nodes.

$ ansible all -m apt -a ‘name=tomcat8 state=absent purge=yes’ -b


$ ansible all -m apt -a ‘name=tomcat8 state=present’ -b

$ ansible all -m copy -a ‘src=tomcat-users.xml dest=/etc/tomcat8’ -b
$ ansible all -m replace -a ‘regexp=8080 replace=9090 path=/etc/tomcat8/server.xml’ -b
$ ansible all -m service -a ‘name=tomcat8 state=restarted’ -b

To check tomcat is running individually on all servers,
take the private ip of all nodes
172.31.11.96
172.31.6.207
172.31.12.138

$ ansible all -m uri -a ‘url=http://172.31.11.96:9090’
It returns status as 200

Similarly check the other two nodes
$ ansible all -m uri -a ‘url=http://172.31.6.207:9090’
$ ansible all -m uri -a ‘url=http://172.31.12.138:9090’

+++++++++++++++++++++
Notes:
Requirement.

I want to install tomcat all modules.Copy tomcat-users.xml in all managed nodes.
Change port number of tomcat from 8080 to 9090. Restart the tomcat8 service.
Finally i want to check url is reachable or not.

$ ansible all -m apt -a ‘name=tomcat8 state=present’ -b

$ ansible all -m copy -a ‘src=tomcat-users.xml dest=/etc/tomcat8’ -b
$ ansible all -m replace -a ‘regexp=8080 replace=9090 path=/etc/tomcat8/server.xml’ -b
$ ansible all -m service -a ‘name=tomcat8 state=restarted’ -b

To check tomcat is running individually on all servers,
take the private ip of all nodes
172.31.11.96
172.31.6.207
172.31.12.138

$ ansible all -m uri -a ‘url=http://172.31.11.96:9090 status=200’
It returns status as 200

Similarly check the other two nodes
$ ansible all -m uri -a ‘url=http://172.31.6.207:9090 status=200’
$ ansible all -m uri -a ‘url=http://172.31.12.138:9090 status=200’

Play books

Notes:
Adhoc commands are capable of working only on one module and one set of arguments.
When we want to perform complex configuration management activities,
adhoc commands will be difficult to manage.

In such scenarios, we use play books.
Play book is combination of plays.
Each play is designed to do some activity on the managed nodes.
These plays are created to work on single host or a group of hosts or all the hosts.

The main advantage of play books is reusability.
Play books are created using yaml files.

$ mkdir playbooks
$ cd playbooks
$ vim playbook1.yml
INSERT mode


  • name: Install git and clone a remote repository hosts: all tasks:
    • name: Install git
      apt:
      name: git
      state: present
      update_cache: yes
    • name: clone remote git repository
      git:
      repo: https://github.com/sunilkumark11/git-9am-batch.git
      dest: /home/ubuntu/newgit

To check the syntax:
$ ansible-playbook playbook1.yml –syntax-check

( Do not use tab when creating yml file )

To run the playbook
$ ansible-playbook playbook1.yml -b

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