GitHub - eoumenwa/ansible: Toddling into Ansible.

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Name		Name	Last commit message	Last commit date
Latest commit History 15 Commits
playbooks		playbooks
Readme		Readme
ansible.cfg		ansible.cfg
ansibledev		ansibledev
database.yml		database.yml
loadbalancer.yml		loadbalancer.yml
webserver.yml		webserver.yml
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This is file contains details of my first steps in Ansible
Although I am proceeding quite slowly, I appreciate the little steps.

 ANSIBLE****************************************************************************************************
 Ansible Hands on started today 3.15.2021
 I may have to dislodge the bulk of these files 
 but wait for it.

Last login: Mon Mar 15 14:02:31 2021 from 73.152.119.181
To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.

ubuntu@ip-172-31-31-121:~$ sudo apt update
Get:40 http://security.ubuntu.com/ubuntu focal-security/multiverse amd64 c-n-f Metadata [340 B]
Fetched 18.3 MB in 3s (5712 kB/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done
26 packages can be upgraded. Run 'apt list --upgradable' to see them.

ubuntu@ip-172-31-31-121:~$ sudo apt install software-properties-common
Reading package lists... Done
Building dependency tree
Reading state information... Done
software-properties-common is already the newest version (0.98.9.4).
software-properties-common set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 26 not upgraded.



ubuntu@ip-172-31-31-121:~$ sudo apt-add-repository --yes --update ppa:ansible/ansible
Hit:1 http://us-east-2.ec2.archive.ubuntu.com/ubuntu focal InRelease
Fetched 19.2 kB in 1s (24.9 kB/s)
Reading package lists... Done

ubuntu@ip-172-31-31-121:~$ sudo apt install ansible
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  ieee-data python3-argcomplete python3-crypto python3-dnspython python3-jmespath python3-kerberos python3-libcloud
  python3-lockfile python3-netaddr python3-ntlm-auth python3-requests-kerberos python3-requests-ntlm python3-selinux
  python3-winrm python3-xmltodict
Suggested packages:
  cowsay sshpass python-lockfile-doc ipython3 python-netaddr-docs
The following NEW packages will be installed:
  ansible ieee-data python3-argcomplete python3-crypto python3-dnspython python3-jmespath python3-kerberos
  python3-libcloud python3-lockfile python3-netaddr python3-ntlm-auth python3-requests-kerberos
  python3-requests-ntlm python3-selinux python3-winrm python3-xmltodict
0 upgraded, 16 newly installed, 0 to remove and 26 not upgraded.
Need to get 9643 kB of archives.
After this operation, 90.2 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://us-east-2.ec2.archive.ubuntu.com/ubuntu focal/main amd64 python3-crypto amd64 2.6.1-13ubuntu2 [237 kB]
Setting up python3-winrm (0.3.0-2) ...
Setting up ansible (2.9.6+dfsg-1) ...
Processing triggers for man-db (2.9.1-1) ...
ubuntu@ip-172-31-31-121:~$


ubuntu@ip-172-31-31-121:~$ ansible --version
ansible 2.9.6
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/ubuntu/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3/dist-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.8.5 (default, Jul 28 2020, 12:59:40) [GCC 9.3.0]


ubuntu@ip-172-31-31-121:~$ ansible-playbook --version
ansible-playbook 2.9.6
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/ubuntu/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3/dist-packages/ansible
  executable location = /usr/bin/ansible-playbook
  python version = 3.8.5 (default, Jul 28 2020, 12:59:40) [GCC 9.3.0]


ubuntu@ip-172-31-31-121:~$ ansible-galaxy --help
usage: ansible-galaxy [-h] [--version] [-v] TYPE ...

Perform various Role and Collection related operations.

positional arguments:
  TYPE
    collection   Manage an Ansible Galaxy collection.
    role         Manage an Ansible Galaxy role.

optional arguments:
  --version      show program's version number, config file location, configured module search path, module
                 location, executable location and exit
  -h, --help     show this help message and exit
  -v, --verbose  verbose mode (-vvv for more, -vvvv to enable connection debugging)



ubuntu@ip-172-31-31-121:~$
ubuntu@ip-172-31-31-121:~$ ansible --list-hosts all

[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match
'all'
  hosts (0):
ubuntu@ip-172-31-31-121:~$
ubuntu@ip-172-31-31-121:~$
ubuntu@ip-172-31-31-121:~$ sudo vi /etc/ansible/hosts
ubuntu@ip-172-31-31-121:~$
ubuntu@ip-172-31-31-121:~$ pwd
/home/ubuntu
ubuntu@ip-172-31-31-121:~$ ls -l
total 0
ubuntu@ip-172-31-31-121:~$ ls -ltr
total 0
ubuntu@ip-172-31-31-121:~$ ls -la
total 40
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 15:36 .
drwxr-xr-x 3 root   root   4096 Mar 15 13:44 ..
-rw------- 1 ubuntu ubuntu  124 Mar 15 15:36 .Xauthority
drwxrwxr-x 3 ubuntu ubuntu 4096 Mar 15 14:34 .ansible
-rw------- 1 ubuntu ubuntu   47 Mar 15 14:16 .bash_history
-rw-r--r-- 1 ubuntu ubuntu  220 Feb 25  2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25  2020 .bashrc
drwx------ 2 ubuntu ubuntu 4096 Mar 15 14:02 .cache
-rw-r--r-- 1 ubuntu ubuntu  807 Feb 25  2020 .profile
drwx------ 2 ubuntu ubuntu 4096 Mar 15 13:44 .ssh
-rw-r--r-- 1 ubuntu ubuntu    0 Mar 15 14:27 .sudo_as_admin_successful
ubuntu@ip-172-31-31-121:~$
ubuntu@ip-172-31-31-121:~$
ubuntu@ip-172-31-31-121:~$ cd .ansible
ubuntu@ip-172-31-31-121:~/.ansible$ ls
tmp
ubuntu@ip-172-31-31-121:~/.ansible$ ls -la
total 12
drwxrwxr-x 3 ubuntu ubuntu 4096 Mar 15 14:34 .
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 15:36 ..
drwx------ 2 ubuntu ubuntu 4096 Mar 15 15:41 tmp
ubuntu@ip-172-31-31-121:~/.ansible$
ubuntu@ip-172-31-31-121:~/.ansible$
ubuntu@ip-172-31-31-121:~/.ansible$ vim ansibledev
ubuntu@ip-172-31-31-121:~/.ansible$ cat ansibledev
[loadbalancer]
lb01

[webserver]
app01
app02

[database]
db01

[control]
control
ubuntu@ip-172-31-31-121:~/.ansible$ ls
ansibledev  tmp
ubuntu@ip-172-31-31-121:~/.ansible$ mv ansibledev /home/ubuntu/ansibledev
ubuntu@ip-172-31-31-121:~/.ansible$ cd ..
ubuntu@ip-172-31-31-121:~$ ls -l
total 4
-rw-rw-r-- 1 ubuntu ubuntu 81 Mar 15 15:52 ansibledev
ubuntu@ip-172-31-31-121:~$ ansible -i ansibledev --list-hosts all
[WARNING]: Found both group and host with same name: control
  hosts (5):
    lb01
    app01
    app02
    db01
    control
ubuntu@ip-172-31-31-121:~$ cd .ansible/
ubuntu@ip-172-31-31-121:~/.ansible$ ansible -i ansibledev --list-hosts all
[WARNING]: Unable to parse /home/ubuntu/.ansible/ansibledev as an inventory source
[WARNING]: No inventory was parsed, only implicit localhost is available
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match
'all'
  hosts (0):
ubuntu@ip-172-31-31-121:~/.ansible$ mv /home/ubuntu/ansibledev /.ansible/ansibledev
mv: cannot move '/home/ubuntu/ansibledev' to '/.ansible/ansibledev': No such file or directory
ubuntu@ip-172-31-31-121:~/.ansible$ cd ..
ubuntu@ip-172-31-31-121:~$ mv /home/ubuntu/ansibledev /.ansible/ansibledev
mv: cannot move '/home/ubuntu/ansibledev' to '/.ansible/ansibledev': No such file or directory
ubuntu@ip-172-31-31-121:~$ pwd
/home/ubuntu
ubuntu@ip-172-31-31-121:~$ ls -l
total 4
-rw-rw-r-- 1 ubuntu ubuntu 81 Mar 15 15:52 ansibledev
ubuntu@ip-172-31-31-121:~$ mv /home/ubuntu/ansibledev .ansible/ansibledev
ubuntu@ip-172-31-31-121:~$
ubuntu@ip-172-31-31-121:~$ ls -l
total 0
ubuntu@ip-172-31-31-121:~$ cd .ansible/
ubuntu@ip-172-31-31-121:~/.ansible$ ls -la
total 16
drwxrwxr-x 3 ubuntu ubuntu 4096 Mar 15 16:00 .
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 16:00 ..
-rw-rw-r-- 1 ubuntu ubuntu   81 Mar 15 15:52 ansibledev
drwx------ 2 ubuntu ubuntu 4096 Mar 15 15:57 tmp
ubuntu@ip-172-31-31-121:~/.ansible$ ansible -i ansibledev --list-hosts all
[WARNING]: Found both group and host with same name: control
  hosts (5):
    lb01
    app01
    app02
    db01
    control
ubuntu@ip-172-31-31-121:~/.ansible$
ubuntu@ip-172-31-31-121:~/.ansible$
ubuntu@ip-172-31-31-121:~/.ansible$
Remember to create the inventory file in .ansible directory and also run anisible from there.
Infact to run "ansible -i ansibledev --list-hosts all" from wherever the file is created.

Setting ansible to not run ssh on control host as in line 560 
ubuntu@ip-172-31-31-121:~/.ansible$ cat ansibledev
[loadbalancer]
lb01

[webserver]
app01
app02

[database]
db01

[control]
control ansible_connection=local

ubuntu@ip-172-31-31-121:~/.ansible$ 

Creating new ansible.cfg file to set inventory defaults and not have to use ansible -i [inventory filename]
as in lines 569 and 570
ubuntu@ip-172-31-31-121:~/.ansible$ sudo vi /etc/ansible/ansible.cfg
ubuntu@ip-172-31-31-121:~/.ansible$ sudo vi /etc/ansible/ansible.cfg
ubuntu@ip-172-31-31-121:~/.ansible$ vim ansible.cfg
ubuntu@ip-172-31-31-121:~/.ansible$ cat ansible.cfg
[defaults]
inventory = ./ansibledev
ubuntu@ip-172-31-31-121:~/.ansible$ ls -la
total 20
drwxrwxr-x 3 ubuntu ubuntu 4096 Mar 15 16:22 .
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 16:22 ..
-rw-rw-r-- 1 ubuntu ubuntu   36 Mar 15 16:22 ansible.cfg
-rw-rw-r-- 1 ubuntu ubuntu  106 Mar 15 16:09 ansibledev
drwx------ 2 ubuntu ubuntu 4096 Mar 15 16:09 tmp

running ansible commands without -i filename
ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts all
[WARNING]: Found both group and host with same name: control
  hosts (5):
    lb01
    app01
    app02
    db01
    control
ubuntu@ip-172-31-31-121:~/.ansible$


ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts "*"
[WARNING]: Found both group and host with same name: control
  hosts (5):
    lb01
    app01
    app02
    db01
    control


ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts webserver
[WARNING]: Found both group and host with same name: control
  hosts (2):
    app01
    app02


ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts laodbalancer
[WARNING]: Found both group and host with same name: control
[WARNING]: Could not match supplied host pattern, ignoring: laodbalancer
[WARNING]: No hosts matched, nothing to do
  hosts (0):


ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts loadbalancer
[WARNING]: Found both group and host with same name: control
  hosts (1):
    lb01


ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts app01
[WARNING]: Found both group and host with same name: control
  hosts (1):
    app01


ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts loadbalancer:webserver
[WARNING]: Found both group and host with same name: control
  hosts (3):
    lb01
    app01
    app02


ubuntu@ip-172-31-31-121:~/.ansible$ ansible --list-hosts \!loadbalancer
[WARNING]: Found both group and host with same name: control
  hosts (4):
    app01
    app02
    db01
    control


ubuntu@ip-172-31-31-121:~/.ansible$ ansible -m ping all
[WARNING]: Found both group and host with same name: control
lb01 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname lb01: Temporary failure in name resolution",
    "unreachable": true
}
app01 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname app01: Temporary failure in name resolution",
    "unreachable": true
}
app02 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname app02: Temporary failure in name resolution",
    "unreachable": true
}
db01 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname db01: Temporary failure in name resolution",
    "unreachable": true
}
control | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}

Now I have to configure ssh connection to all hosts*******************************
https://superuser.com/questions/1135766/how-to-ssh-from-one-ec2-instance-to-another
Method 1 - use the same keys on the servers:

Convert the keys to openssh format and upload the private keys to the servers. When you ssh to the destination host, specify the private key file:

ssh -i mykey.pem private.ip.of.other.server
Method 2 - Create new keys

On each server run:

ssh-keygen
Hit enter enter enter. You'll have two files:

.ssh/id_rsa
.ssh/id_rsa.pub
On Server A, cat and copy to clipboard the public key:

cat ~/.ssh/id_rsa.pub
[select and copy to your clipboard]
ssh into Server B, and append the contents of that to it's authorized_keys file:

cat >> ~/.ssh/authorized_keys
[paste your clipboard contents]
[ctrl+d to exit]
Now ssh from server A:

ssh -i ~/.ssh/id_rsa "private.ip.of.other.server"

See the results **************************

ubuntu@ip-172-31-31-121:~/.ansible$ ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/ubuntu/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/ubuntu/.ssh/id_rsa
Your public key has been saved in /home/ubuntu/.ssh/id_rsa.pub
The key fingerprint is:
SHA256:zv3Hd/rbNbuhV5tB8Nvah8FKHtHytkwwhuyqMg/iKoQ ubuntu@ip-172-31-31-121
The key's randomart image is:
+---[RSA 3072]----+
|                 |
|             .   |
|         . . .o  |
|          o * .o |
|.       S. . B. o|
|E.     o .. o *oo|
|. . .   o..o B O*|
|.. .o.  .  .o O+@|
|o..  +o.    .ooBB|
+----[SHA256]-----+
ubuntu@ip-172-31-31-121:~/.ansible$ cd ..
ubuntu@ip-172-31-31-121:~$ ls -la
total 44
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 16:22 .
drwxr-xr-x 3 root   root   4096 Mar 15 13:44 ..
-rw------- 1 ubuntu ubuntu  124 Mar 15 15:36 .Xauthority
drwxrwxr-x 4 ubuntu ubuntu 4096 Mar 15 16:40 .ansible
-rw------- 1 ubuntu ubuntu   47 Mar 15 14:16 .bash_history
-rw-r--r-- 1 ubuntu ubuntu  220 Feb 25  2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25  2020 .bashrc
drwx------ 2 ubuntu ubuntu 4096 Mar 15 14:02 .cache
-rw-r--r-- 1 ubuntu ubuntu  807 Feb 25  2020 .profile
drwx------ 2 ubuntu ubuntu 4096 Mar 15 17:21 .ssh
-rw-r--r-- 1 ubuntu ubuntu    0 Mar 15 14:27 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1740 Mar 15 16:22 .viminfo

ubuntu@ip-172-31-31-121:~$ cd .ssh

ubuntu@ip-172-31-31-121:~/.ssh$ ls -la
total 20
drwx------ 2 ubuntu ubuntu 4096 Mar 15 17:21 .
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 16:22 ..
-rw------- 1 ubuntu ubuntu  395 Mar 15 13:44 authorized_keys
-rw------- 1 ubuntu ubuntu 2610 Mar 15 17:21 id_rsa
-rw-r--r-- 1 ubuntu ubuntu  577 Mar 15 17:21 id_rsa.pub

ubuntu@ip-172-31-31-121:~/.ssh$ chmod 400 id_rsa.pub

ubuntu@ip-172-31-31-121:~/.ssh$ ls -la
total 20
drwx------ 2 ubuntu ubuntu 4096 Mar 15 17:21 .
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 16:22 ..
-rw------- 1 ubuntu ubuntu  395 Mar 15 13:44 authorized_keys
-rw------- 1 ubuntu ubuntu 2610 Mar 15 17:21 id_rsa
-r-------- 1 ubuntu ubuntu  577 Mar 15 17:21 id_rsa.pub

I copied the content of id_rsa.pub below and appended to the authorized_keys file 
of the instance that I want to connect to using cat >> ~/.ssh/authorized_keys. Press ctrl + D to exit


ubuntu@ip-172-31-31-121:~/.ssh$ cat id_rsa.pub
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABgQDFr/6DHsHD6HgZ7hxgIGN4lMwhW9iXU/cjPBDQcXpMf1qqRT8x6MvXimcUqFhfLGCXWD3gYVrs
ZYmw033WvJkpkRCunt08okbzNey8u7zmol5PzGdgIzPzfPlHH6OmPcn/pX8JDBu9OSA8nmLRr2tOrxg6yHWRBQX4Yc7Ztqst9cFutBJNQe7ViR1
k/lVWlOEEU2Vur6qTDGGp3D0GyCVA/But7zuOo+c/eUuO8RuFZ3lHIC8VygHqOWKEsBpJlLC8aUT06K8orw4sl6sgAVa+QOAfMGwliKH0JAbZDg
6kuInTrPJzfD08P2zYTXwqrMk0pjhNkdLMAv/cwPIir5aSsVwlyjojyQG7kzqEHkNVNWXq5tll5ActeTth44kyp0iptrAz4ftnRCIPYEaKspgIu
FNGniJr/lmPLThwt/PPSqPZBuKp6iR0mFEn2/ygITuhRwA2nR5nzjoVRYXmDWO1ApTazQkpi3YzuMdkK7z5KinXdc1EFSfNW5x9O
H1JdFs= ubuntu@ip-172-31-31-121


ubuntu@ip-172-31-31-121:~/.ssh$


ubuntu@ip-172-31-31-121:~/.ssh$ cat authorized_keys
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDmRAtXv99iBc/yFklRC8VtYu4HO7MwRbsxSQ6b12UP3+eKuBFdkj4RzNywum
SzgX9NeW74Bs4NP3H9yWhKmFg3cH9a8O8aNCZ2hoDExawd4/DVOU6fYPEfcSptLYvsB2Uhv+H7oFG/WVH4fAAKaPJijj1fjIv5
oMfWCGlnMQOjq6MfihgZnfR84/XE/Pl0OXgJQUUJI1S29G595p3twsQ23puZqZ5eCs5ZLNMKDWlMeXdIrG2I2OhAaOv+hMUGO3
NOQfxiKGVxs/B0sswju7PiFWMRZerNTf3VXjSG5YjPQJqaWnWgJDFkqsV6czzusIKrCI7JwQkIDnFFYV9ew0JD testkeyubuntu

Then I ran the "ssh -i command"

ubuntu@ip-172-31-31-121:~/.ssh$ ssh -i ~/.ssh/id_rsa 172.31.22.126

The authenticity of host '172.31.22.126 (172.31.22.126)' can't be established.
ECDSA key fingerprint is SHA256:SoY6gkS1nh8Ft+1lilmwCwq+a8cHfFd5oOIZc0+9TeI.
Are you sure you want to continue connecting (yes/no/[fingerprint])? y
Please type 'yes', 'no' or the fingerprint: yes
Warning: Permanently added '172.31.22.126' (ECDSA) to the list of known hosts.
Welcome to Ubuntu 20.04.2 LTS (GNU/Linux 5.4.0-1038-aws x86_64)

 * Documentation:  https://help.ubuntu.com
 * Management:     https://landscape.canonical.com
 * Support:        https://ubuntu.com/advantage

  System information as of Mon Mar 15 17:57:37 UTC 2021

  System load:  0.08              Processes:             105
  Usage of /:   16.4% of 7.69GB   Users logged in:       1
  Memory usage: 24%               IPv4 address for eth0: 172.31.22.126
  Swap usage:   0%


1 update can be installed immediately.
0 of these updates are security updates.
To see these additional updates run: apt list --upgradable


The list of available updates is more than a week old.
To check for new updates run: sudo apt update

Last login: Mon Mar 15 14:20:21 2021 from 73.152.119.181
To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.

ubuntu@ip-172-31-22-126:~$ logout

Connection to 172.31.22.126 closed.

ubuntu@ip-172-31-31-121:~/.ssh$
I will repeat thesame process for webserver and database having done so for the laodbalancer.

All done.

So we continue to ping all hosts in ansible.

ubuntu@ip-172-31-31-121:~/.ssh$ ansible -m ping all
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match
'all'
ubuntu@ip-172-31-31-121:~/.ssh$ cd ..
ubuntu@ip-172-31-31-121:~$ cd ansible
-bash: cd: ansible: No such file or directory
ubuntu@ip-172-31-31-121:~$ cd .ansible
ubuntu@ip-172-31-31-121:~/.ansible$ ansible -m ping all
[WARNING]: Found both group and host with same name: control
lb01 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname lb01: Temporary failure in name resolution",
    "unreachable": true
}
app02 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname app02: Temporary failure in name resolution",
    "unreachable": true
}
app01 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname app01: Temporary failure in name resolution",
    "unreachable": true
}
db01 | UNREACHABLE! => {
    "changed": false,
    "msg": "Failed to connect to the host via ssh: ssh: Could not resolve hostname db01: Temporary failure in name resolution",
    "unreachable": true
}
control | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
ubuntu@ip-172-31-31-121:~/.ansible$ ping 172.31.22.126
PING 172.31.22.126 (172.31.22.126) 56(84) bytes of data.
64 bytes from 172.31.22.126: icmp_seq=1 ttl=64 time=0.418 ms
64 bytes from 172.31.22.126: icmp_seq=2 ttl=64 time=0.475 ms
64 bytes from 172.31.22.126: icmp_seq=3 ttl=64 time=0.498 ms

--- 172.31.22.126 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2032ms
rtt min/avg/max/mdev = 0.418/0.463/0.498/0.033 ms

Another failure to connect. I had to edit the config file and added the ip addresses beside the hostnames
per the article in https://www.reddit.com/r/ansible/comments/bniofo/cant_ping_hosts/


ubuntu@ip-172-31-31-121:~/.ansible$ cat ansibledev
[loadbalancer]
lb01 ansible_host=172.31.22.126

[webserver]
app01 ansible_host=172.31.20.227
app02 ansible_host=172.31.20.227

[database]
db01 ansible_host=172.31.23.168

[control]
control ansible_connection=local
ubuntu@ip-172-31-31-121:~/.ansible$ ansible -m ping all
[WARNING]: Found both group and host with same name: control
The authenticity of host '172.31.20.227 (172.31.20.227)' can't be established.
ECDSA key fingerprint is SHA256:4jdjBjaPTzEtPAJW7th7PCsahw0CRmIsP1JLIEd1AFc.
The authenticity of host '172.31.20.227 (172.31.20.227)' can't be established.
ECDSA key fingerprint is SHA256:4jdjBjaPTzEtPAJW7th7PCsahw0CRmIsP1JLIEd1AFc.
Are you sure you want to continue connecting (yes/no/[fingerprint])? control | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
db01 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
lb01 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}

 [ERROR]: User interrupted execution
ubuntu@ip-172-31-31-121:~/.ansible$ ansible -m ping all
[WARNING]: Found both group and host with same name: control
The authenticity of host '172.31.20.227 (172.31.20.227)' can't be established.
ECDSA key fingerprint is SHA256:4jdjBjaPTzEtPAJW7th7PCsahw0CRmIsP1JLIEd1AFc.
The authenticity of host '172.31.20.227 (172.31.20.227)' can't be established.
ECDSA key fingerprint is SHA256:4jdjBjaPTzEtPAJW7th7PCsahw0CRmIsP1JLIEd1AFc.
Are you sure you want to continue connecting (yes/no/[fingerprint])? control | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
lb01 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
db01 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
yes
app01 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
yes
app02 | SUCCESS => {
    "ansible_facts": {
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false,
    "ping": "pong"
}
ubuntu@ip-172-31-31-121:~/.ansible$

Note: I think I had to answer the YES from trying to ssh to all the hosts the first time before 
I could connect safely. This explained why app01 and app02 did not ping until I entered yes.

ubuntu@ip-172-31-31-121:~/.ansible$ ansible -m command -a "hostname" all
[WARNING]: Found both group and host with same name: control
control | CHANGED | rc=0 >>
ip-172-31-31-121
lb01 | CHANGED | rc=0 >>
ip-172-31-22-126
db01 | CHANGED | rc=0 >>
ip-172-31-23-168
app01 | CHANGED | rc=0 >>
ip-172-31-20-227
app02 | CHANGED | rc=0 >>
ip-172-31-20-227
ubuntu@ip-172-31-31-121:~/.ansible$

A deviation to git *****************************
ubuntu@ip-172-31-31-121:~/.ansible$ git init
Initialized empty Git repository in /home/ubuntu/.ansible/.git/

ubuntu@ip-172-31-31-121:~/.ansible$ git status
On branch master

No commits yet

Untracked files:
  (use "git add <file>..." to include in what will be committed)
        ansible.cfg
        ansibledev
        playbooks/

nothing added to commit but untracked files present (use "git add" to track)

ubuntu@ip-172-31-31-121:~/.ansible$ git add .
ubuntu@ip-172-31-31-121:~/.ansible$ git status
On branch master

No commits yet

Changes to be committed:
  (use "git rm --cached <file>..." to unstage)
        new file:   ansible.cfg
        new file:   ansibledev
        new file:   playbooks/hostname.yml

ubuntu@ip-172-31-31-121:~/.ansible$ git commit -m "Initial Commit"
[master (root-commit) e3011fe] Initial Commit
 Committer: Ubuntu <ubuntu@ip-172-31-31-121.us-east-2.compute.internal>
Your name and email address were configured automatically based
on your username and hostname. Please check that they are accurate.
You can suppress this message by setting them explicitly. Run the
following command and follow the instructions in your editor to edit
your configuration file:

    git config --global --edit

After doing this, you may fix the identity used for this commit with:

    git commit --amend --reset-author

 3 files changed, 14 insertions(+)
 create mode 100644 ansible.cfg
 create mode 100644 ansibledev
 create mode 100644 playbooks/hostname.yml
ubuntu@ip-172-31-31-121:~/.ansible$ git config --global --edit

ubuntu@ip-172-31-31-121:~/.ansible$ git remote -v
ubuntu@ip-172-31-31-121:~/.ansible$ git remote add origin https://github.com/eoumenwa/Ansible.git
ubuntu@ip-172-31-31-121:~/.ansible$ git remote -v
origin  https://github.com/eoumenwa/Ansible.git (fetch)
origin  https://github.com/eoumenwa/Ansible.git (push)

ubuntu@ip-172-31-31-121:~/.ansible$ git push origin master
Username for 'https://github.com': eoumenwa
Password for 'https://eoumenwa@github.com':
Enumerating objects: 6, done.
Counting objects: 100% (6/6), done.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (6/6), 474 bytes | 474.00 KiB/s, done.
Total 6 (delta 0), reused 0 (delta 0)
To https://github.com/eoumenwa/Ansible.git
 * [new branch]      master -> master
ubuntu@ip-172-31-31-121:~/.ansible$


Back to Ansible*********************

ubuntu@ip-172-31-31-121:~/.ansible$ mkdir playbooks
ubuntu@ip-172-31-31-121:~/.ansible$ ls -la
total 28
drwxrwxr-x 5 ubuntu ubuntu 4096 Mar 15 19:18 .
drwxr-xr-x 5 ubuntu ubuntu 4096 Mar 15 19:17 ..
-rw-rw-r-- 1 ubuntu ubuntu   36 Mar 15 16:22 ansible.cfg
-rw-rw-r-- 1 ubuntu ubuntu  214 Mar 15 18:46 ansibledev
drwx------ 2 ubuntu ubuntu 4096 Mar 15 19:03 cp
drwxrwxr-x 2 ubuntu ubuntu 4096 Mar 15 19:18 playbooks
drwx------ 2 ubuntu ubuntu 4096 Mar 15 19:14 tmp
ubuntu@ip-172-31-31-121:~/.ansible$ cd playbooks/
ubuntu@ip-172-31-31-121:~/.ansible/playbooks$ touch hostname.yml
ubuntu@ip-172-31-31-121:~/.ansible/playbooks$ ls -la
total 8
drwxrwxr-x 2 ubuntu ubuntu 4096 Mar 15 19:19 .
drwxrwxr-x 5 ubuntu ubuntu 4096 Mar 15 19:18 ..
-rw-rw-r-- 1 ubuntu ubuntu    0 Mar 15 19:19 hostname.yml
ubuntu@ip-172-31-31-121:~/.ansible/playbooks$ vim hostname.yml
ubuntu@ip-172-31-31-121:~/.ansible/playbooks$ cat hostname.yml
---
    - hosts: all
      tasks:
        - command: hostname
ubuntu@ip-172-31-31-121:~/.ansible/playbooks$ cd ..

ubuntu@ip-172-31-31-121:~/.ansible$ ansible-playbook playbooks/hostname.yml

[WARNING]: Found both group and host with same name: control

PLAY [all] ***************************************************************************************************************

TASK [Gathering Facts] ***************************************************************************************************
ok: [db01]
ok: [control]
ok: [lb01]
ok: [app02]
ok: [app01]

TASK [command] ***********************************************************************************************************
changed: [db01]
changed: [lb01]
changed: [control]
changed: [app02]
changed: [app01]

PLAY RECAP ***************************************************************************************************************
app01                      : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
app02                      : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
control                    : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
db01                       : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0
lb01                       : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

ubuntu@ip-172-31-31-121:~/.ansible$
 Realized I have to be in the ansible directory to run the ansible-playbook 
 commands and refer to file path.
 This yaml is something very tricky. Needing punctuation exactness.

 ubuntu@ip-172-31-31-121:~/.ansible$ vim database.yml
ubuntu@ip-172-31-31-121:~/.ansible$ ansible-playbook database.yml
[WARNING]: Found both group and host with same name: control

PLAY [database] **********************************************************************************************************

TASK [Gathering Facts] ***************************************************************************************************
ok: [db01]

TASK [install mysql-server] **********************************************************************************************
changed: [db01]

PLAY RECAP ***************************************************************************************************************
db01                       : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

ubuntu@ip-172-31-31-121:~/.ansible$


ubuntu@ip-172-31-31-121:~/.ansible$ git status
On branch master
Your branch is up to date with 'origin/master'.

Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git restore <file>..." to discard changes in working directory)
        modified:   playbooks/hostname.yml

Untracked files:
  (use "git add <file>..." to include in what will be committed)
        database.yml
        loadbalancer.yml

no changes added to commit (use "git add" and/or "git commit -a")
ubuntu@ip-172-31-31-121:~/.ansible$ git add .
ubuntu@ip-172-31-31-121:~/.ansible$ git status
On branch master
Your branch is up to date with 'origin/master'.

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
        new file:   database.yml
        new file:   loadbalancer.yml
        modified:   playbooks/hostname.yml

ubuntu@ip-172-31-31-121:~/.ansible$ git commit -m "Added some yml files"
[master 51a3461] Added some yml files
 3 files changed, 16 insertions(+)
 create mode 100644 database.yml
 create mode 100644 loadbalancer.yml
ubuntu@ip-172-31-31-121:~/.ansible$ git push -u origin master
Username for 'https://github.com': eoumenwa
Password for 'https://eoumenwa@github.com':
Enumerating objects: 9, done.
Counting objects: 100% (9/9), done.
Compressing objects: 100% (5/5), done.
Writing objects: 100% (6/6), 752 bytes | 752.00 KiB/s, done.
Total 6 (delta 0), reused 0 (delta 0)
To https://github.com/eoumenwa/Ansible.git
   c2ce40d..51a3461  master -> master
Branch 'master' set up to track remote branch 'master' from 'origin'.
ubuntu@ip-172-31-31-121:~/.ansible$ vim loadbalancer.yml


ubuntu@ip-172-31-31-121:~/.ansible$ ansible-playbook loadbalancer.yml
[WARNING]: Found both group and host with same name: control

PLAY [loadbalancer] ******************************************************************************************************

TASK [Gathering Facts] ***************************************************************************************************
ok: [lb01]

TASK [install nginx] *****************************************************************************************************
fatal: [lb01]: FAILED! => {"changed": false, "msg": "Failed to lock apt for exclusive operation"}

PLAY RECAP ***************************************************************************************************************
lb01                       : ok=1    changed=0    unreachable=0    failed=1    skipped=0    rescued=0    ignored=0

ubuntu@ip-172-31-31-121:~/.ansible$

I had to add become=true to the code line to clear the above error.

ubuntu@ip-172-31-31-121:~/.ansible$ ansible-playbook loadbalancer.yml
[WARNING]: Found both group and host with same name: control

PLAY [loadbalancer] ******************************************************************************************************

TASK [Gathering Facts] ***************************************************************************************************
ok: [lb01]

TASK [install nginx] *****************************************************************************************************
changed: [lb01]

PLAY RECAP ***************************************************************************************************************
lb01                       : ok=2    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0

ubuntu@ip-172-31-31-121:~/.ansible$

ubuntu@ip-172-31-31-121:~/.ansible$ vim webserver.yml
ubuntu@ip-172-31-31-121:~/.ansible$ ansible-playbook webserver.yml
[WARNING]: Found both group and host with same name: control

PLAY [webserver] *********************************************************************************************************

TASK [Gathering Facts] ***************************************************************************************************
ok: [app02]
ok: [app01]

TASK [install apache2] ***************************************************************************************************
[DEPRECATION WARNING]: Invoking "apt" only once while using a loop via squash_actions is deprecated. Instead of using a
loop to supply multiple items and specifying `name: "{{item}}"`, please use `name: ['apache2', 'libapache2-mod-wsgi',
'python-pip', 'python-virtualenv']` and remove the loop. This feature will be removed in version 2.11. Deprecation
warnings can be disabled by setting deprecation_warnings=False in ansible.cfg.
[DEPRECATION WARNING]: Invoking "apt" only once while using a loop via squash_actions is deprecated. Instead of using a
loop to supply multiple items and specifying `name: "{{item}}"`, please use `name: ['apache2', 'libapache2-mod-wsgi',
'python-pip', 'python-virtualenv']` and remove the loop. This feature will be removed in version 2.11. Deprecation
warnings can be disabled by setting deprecation_warnings=False in ansible.cfg.
failed: [app02] (item=['apache2', 'libapache2-mod-wsgi', 'python-pip', 'python-virtualenv']) => {"ansible_loop_var": "item", "changed": false, "item": ["apache2", "libapache2-mod-wsgi", "python-pip", "python-virtualenv"], "msg": "Failed to lock apt for exclusive operation"}
failed: [app01] (item=['apache2', 'libapache2-mod-wsgi', 'python-pip', 'python-virtualenv']) => {"ansible_loop_var": "item", "changed": false, "item": ["apache2", "libapache2-mod-wsgi", "python-pip", "python-virtualenv"], "msg": "No package matching 'python-pip' is available"}

PLAY RECAP ***************************************************************************************************************
app01                      : ok=1    changed=0    unreachable=0    failed=1    skipped=0    rescued=0    ignored=0
app02                      : ok=1    changed=0    unreachable=0    failed=1    skipped=0    rescued=0    ignored=0

ubuntu@ip-172-31-31-121:~/.ansible$

Seems I need to remove the jinja concept {{}} as below

---
  - hosts: webserver
    become: true
    tasks:
      - name: install apache2
        apt: name={{item}} state=present update_cache=yes
        with_items:
          - apache2
          - libapache2-mod-wsgi
          - python-pip
          - python-virtualenv

---
  -hosts: webserver
    become: true
    tasks:
      -name:install apache2
        apt:name:['apache2', 'libapache2-mod-wsgi', 'python-pip', 'python-virtualenv'] state=present update_cache=yes
       


ubuntu@ip-172-31-31-121:~/.ansible$ ansible-playbook webserver.yml
[WARNING]: Found both group and host with same name: control

PLAY [install webserver components] **************************************************************************************

TASK [Gathering Facts] ***************************************************************************************************
ok: [app02]
ok: [app01]

TASK [Install packages] **************************************************************************************************
ok: [app02] => (item=apache2)
ok: [app01] => (item=apache2)
ok: [app01] => (item=libapache2-mod-wsgi)
ok: [app02] => (item=libapache2-mod-wsgi)
failed: [app02] (item=python-pip) => {"ansible_loop_var": "item", "changed": false, "item": "python-pip", "msg": "No package matching 'python-pip' is available"}
failed: [app01] (item=python-pip) => {"ansible_loop_var": "item", "changed": false, "item": "python-pip", "msg": "No package matching 'python-pip' is available"}
failed: [app02] (item=python-virtualenv) => {"ansible_loop_var": "item", "changed": false, "item": "python-virtualenv", "msg": "No package matching 'python-virtualenv' is available"}
failed: [app01] (item=python-virtualenv) => {"ansible_loop_var": "item", "changed": false, "item": "python-virtualenv", "msg": "No package matching 'python-virtualenv' is available"}

PLAY RECAP ***************************************************************************************************************
app01                      : ok=1    changed=0    unreachable=0    failed=1    skipped=0    rescued=0    ignored=0
app02                      : ok=1    changed=0    unreachable=0    failed=1    skipped=0    rescued=0    ignored=0

ubuntu@ip-172-31-31-121:~/.ansible$



I will ignore this playbook and continue. For some reasons, the last two python packages are not installing.
BUt I have learnt a few tricks about working with old documentations and deprecation_warnings

3.17.2021
At this point, it seems my instances are approaching my monthly limit so am thinking of running Ansible locally
to reduce bills since I already understood the concept.

Services: service
Starting with loadbalancer
---
  - hosts: loadbalancer
    become: true
    tasks:
      - name: install nginx
        apt: name=nginx state=present update_cache=yes
      - name: ensure nginx started
        service: name=nginx state=started enabled=
        
        Testing endpoint
        run
        wget = q0= http://lb01 | less
        You will get welcome to nginx

        create new file....control.yml

---
- name: install tools
  hosts: control
  become: true
  tasks:
    - name: Install curl
      package:
        name: "{{item}}"
        state: present
        update_cache: yes
      loop:
      - curl

run the playbook
run which curl
run curl lb01

update webserver.yml as below

---
- name: install webserver components
  hosts: webserver
  become: true
  tasks:
    - name: Install packages
      package:
        name: "{{item}}"
        state: present
        update_cache: yes
      loop:
      - apache2
      - libapache2-mod-wsgi
      - python-pip
      - python-virtualenv

    - name: ensure apache2 started
      service: name=apache2 state=started enabled=yes

Append database.yml as below


 ---
 - hosts: database
   become: true
   tasks:
     - name: install mysql-server
       apt: name=mysql-server state=present update_cache=yes
    
     - name: ensure mysql started
       service: name=mysql state=started enabled=yes


Support Playbook 1 - Stack Restart****************************
Create a file in .ansible/playbooks/stack_restart.yml
This is like a basic way to restart Services
Using handlers
Modify webserver.yml as below to include module, handlers and notify

---
- name: install webserver components
  hosts: webserver
  become: true
  tasks:
    - name: Install packages
      package:
        name: "{{item}}"
        state: present
        update_cache: yes
      loop:
      - apache2
      - libapache2-mod-wsgi
      - python-pip
      - python-virtualenv

    - name: ensure apache2 started
      service: name=apache2 state=started enabled=yes

    - name: ensure mod_wsgi enabled
      apache2_module: state=present name=wsgi  
      notify: restart apache2

  handlers:
    - name: restart apache2
      services: name=apache2 state=restarted



Files: copy ***************************************
Get applications moved over to the hosts using simple python flask.

On the webserver, add a new task (You need a folder demo/ and /app) and
a demo.cnf file that will be used to replace the apache default site


---
- name: install webserver components
  hosts: webserver
  become: true
  tasks:
    - name: Install packages
      package:
        name: "{{item}}"
        state: present
        update_cache: yes
      loop:
      - apache2
      - libapache2-mod-wsgi
      - python-pip
      - python-virtualenv

    - name: ensure apache2 started
      service: name=apache2 state=started enabled=yes

    - name: ensure mod_wsgi enabled
      apache2_module: state=present name=wsgi  
      notify: restart apache2

    - name: copy demo app source
      copy: src=demo/app/ dest=/var/www/demo mode=0755
      notify: restart apache2

    - name: copy apache virtual host config
      copy: src=demo/demo.cnf dest=/etc/apache2/sites-available mode=0755
      notify: restart apache2

  handlers:
    - name: restart apache2
      services: name=apache2 state=restarted

Run webserver.yml

If you run curl appo1, notice you are still responding with the default apache2 page.

Modify webserver.yml as below

---
- name: install webserver components
  hosts: webserver
  become: true
  tasks:
    - name: Install packages
      package:
        name: "{{item}}"
        state: present
        update_cache: yes
      loop:
      - apache2
      - libapache2-mod-wsgi
      - python-pip
      - python-virtualenv

    - name: ensure apache2 started
      service: name=apache2 state=started enabled=yes

    - name: ensure mod_wsgi enabled
      apache2_module: state=present name=wsgi  
      notify: restart apache2

    - name: copy demo app source
      copy: src=demo/app/ dest=/var/www/demo mode=0755
      notify: restart apache2

    - name: copy apache virtual host config
      copy: src=demo/demo.cnf dest=/etc/apache2/sites-available mode=0755
      notify: restart apache2

    - name: setup python virtualenv
      pip: requirements=/var/www/demo/requirements.txt virtualenv=/var/www/demo/.venv
      notify: restart apache2

    - name: de-activate default apache site
      file: path=/etc/apache2/sites-enabled/000-default.conf state=absent
      notify: restart apache2

    - name: activate demo apache site
      file: src=/etc/apache2/sites-available/demo.conf dest=/etc/apache2/sites-enabled/demo.conf state=link
      notify: restart apache2
  handlers:
    - name: restart apache2
      services: name=apache2 state=restarted


Files:file

---
- name: install webserver components
  hosts: webserver
  become: true
  tasks:
    - name: Install packages
      package:
        name: "{{item}}"
        state: present
        update_cache: yes
      loop:
      - apache2
      - libapache2-mod-wsgi
      - python-pip
      - python-virtualenv

    - name: ensure apache2 started
      service: name=apache2 state=started enabled=yes

    - name: ensure mod_wsgi enabled
      apache2_module: state=present name=wsgi  
      notify: restart apache2

    - name: copy demo app source
      copy: src=demo/app/ dest=/var/www/demo mode=0755
      notify: restart apache2

    - name: copy apache virtual host config
      copy: src=demo/demo.cnf dest=/etc/apache2/sites-available mode=0755
      notify: restart apache2

    - name: setup python virtualenv
+     pip: requirements=/var/www/demo/requirements.txt virtualenv=/var/www/demo/.venv
+     notify: restart apache2
    
    - name: de-activate default apache site
+      file: path=/etc/apache2/sites-enabled/000-default.conf state=absent
+      notify: restart apache2
+
+    - name: activate demo apache site
+      file: src=/etc/apache2/sites-available/demo.conf dest=/etc/apache2/sites-enabled/demo.conf state=link
+      notify: restart apache2

  handlers:
    - name: restart apache2
      services: name=apache2 state=restarted
      
      Run curl app01 and app02 and notice the response from the webservers.
      curl lb01 still returns default nginx page at this time.
      NExt is to correct this to actually start loadbalancing. Configure nginx to load balance against the two servers at the backend
      Edit loadbalancer.yml
      
     First create a new folder....templates in .ansible root
      a file nginx.conf.j2
      
 upstream demo {
+{% for server in groups.webserver %}
+    server {{ server }};
+{% endfor %}
+}
+
+server {
+    listen 80;
+
+    location / {
+        proxy_pass http://demo;
+    }
+}
      
   
   laodbalancer.yml

+
+    - name: configure nginx site
+      template: src=templates/nginx.conf.j2 dest=/etc/nginx/sites-available/demo mode=0644
+      notify: restart nginx
+
+    - name: de-activate default nginx site
+      file: path=/etc/nginx/sites-enabled/default state=absent
+      notify: restart nginx
+
+    - name: activate demo nginx site
+      file: src=/etc/nginx/sites-available/demo dest=/etc/nginx/sites-enabled/demo state=link
+      notify: restart nginx

+  handlers:
+    - name: restart nginx
+      service: name=nginx state=restarted


Lineinfile
Testing db connection from python to mysql host


Edit database.yml

     - name: ensure mysql started
       service: name=mysql state=started enabled=yes
+
+    - name: ensure mysql listening on all ports
+      lineinfile: dest=/etc/mysql/my.cnf regexp=^bind-address 
                   line="bind-address = 0.0.0.0"
+      notify: restart mysql
+
+  handlers:
+    - name: restart mysql
+      service: name=mysql state=restarted

APlication module to add python dependencies of mysql for python.
Edit webserver.yml

         - libapache2-mod-wsgi
         - python-pip
         - python-virtualenv
+        - python-mysqldb
 
     - name: ensure apache2 started
       service: name=apache2 state=started enabled=yes
       
       Edit database.yml
       
       - hosts: database
   become: true
   tasks:
+    - name: install tools
+      apt: name={{item}} state=present update_cache=yes
+      with_items:
+        - python-mysqldb
+
     - name: install mysql-server
       apt: name=mysql-server state=present update_cache=yes
 

       lineinfile: dest=/etc/mysql/my.cnf regexp=^bind-address line="bind-address = 0.0.0.0"
       notify: restart mysql
 
+    - name: create demo database
+      mysql_db: name=demo state=present
+
+    - name: create demo user
+      mysql_user: name=demo password=demo priv=demo.*:ALL host='%' state=present
+
   handlers:
     - name: restart mysql
       service: name=mysql state=restarted
       
       curl app01/db
       curl app02/db
       curl lb01/db
       
       Support playbook. wait_for
       create file....  stack_status.yml