Ansible is the leading Open Source configuration management system. It makes it easy for administrators and operations teams to control thousands of servers from central machine without installing agents on them.
Ansible is the simplest to use and manage when compared to other configuration management systems such as Puppet, Chef and Salt. It is easy to install, learn, and use. The only dependency required on the remote server is SSH service and Python.
Install and Configure Ansible on CentOS 8 / RHEL 8 using the steps below.
Step 1: Install Python on RHEL 8 / CentOS 8
Install and Set your default Python on RHEL 8 using the guide below.
How to Install Python 3 / Python 2.7 on RHEL 8
Once it has been installed, proceed to install Pip which is a Python package manager used to install Ansible.
If you’re using Python3, install python3-pip package.
sudo dnf -y install python3-pip sudo pip3 install --upgrade pip
For Python2 users you have to install python2-pip
sudo dnf -y install python2-pip sudo pip2 install --upgrade pip
Step 2: Install Ansible on RHEL 8 / CentOS 8
There are two methods from which you can install Ansible on CentOS 8 / RHEL 8.
Method 1: Install Ansible on CentOS 8 / RHEL 8 from EPEL
Add EPEL repository to your CentOS 8 / RHEL 8 system.
sudo dnf -y install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpmThen Enable EPEL playground repository and install Ansible on CentOS 8 / RHEL 8 from it.
sudo dnf install --enablerepo epel-playground ansibleThis will default to using Python 3, so some Python 3 packages are installed.
Dependencies resolved.
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Package Arch Version Repository Size
===================================================================================================================================================
Installing:
ansible noarch 2.8.5-2.epel8.playground epel-playground 15 M
Installing dependencies:
python3-jmespath noarch 0.9.0-11.el8 AppStream 45 k
python3-pyasn1 noarch 0.3.7-6.el8 AppStream 126 k
python3-bcrypt x86_64 3.1.6-2.epel8.playground.1 epel-playground 44 k
python3-pynacl x86_64 1.3.0-5.epel8.playground epel-playground 100 k
sshpass x86_64 1.06-9.epel8.playground epel-playground 27 k
libsodium x86_64 1.0.18-2.el8 epel 162 k
Installing weak dependencies:
python3-paramiko noarch 2.4.3-1.epel8.playground epel-playground 289 k
Transaction Summary
===================================================================================================================================================
Install 8 Packages
Total download size: 15 M
Installed size: 81 M
Is this ok [y/N]: yCheck the version of Ansible installed on your CentOS 8 / RHEL 8 system.
$ ansible --version ansible 2.8.5 config file = /etc/ansible/ansible.cfg configured module search path = ['/home/cloud-user/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules'] ansible python module location = /usr/lib/python3.6/site-packages/ansible executable location = /usr/bin/ansible python version = 3.6.8 (default, Sat 25 2020, 08:43:04) [GCC 8.2.1 20180905 (Red Hat 8.2.1-3)]
Method 2: Install Ansible on CentOS 8 / RHEL 8 using pip
Once you have Pip installed, you can use it to get Ansible installed in your CentOS 8 / RHEL 8 machine.
$ pip3 install ansible --user
For Python2 pip, use:
$ pip2 install ansible --user
You can see Ansible installed using the following command:
$ ansible --version ansible 2.7.5 config file = None configured module search path = ['/home/user/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules'] ansible python module location = /home/user/.local/lib/python3.6/site-packages/ansible executable location = /home/user/.local/bin/ansible python version = 3.6.6 (default, Sat 25 2020, 20:10:11) [GCC 8.2.1 20180905 (Red Hat 8.2.1-3)]
Step 3: Testing Ansible on CentOS 8 / RHEL 8 Linux
To test Ansible, you should have OpenSSH service running on the remote server.
$ sudo systemctl status sshd
● sshd.service - OpenSSH server daemon
Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
Active: active (running) since Sat 2020-09-25 20:17:11 UTC; 39min ago
Docs: man:sshd(8)
man:sshd_config(5)
Main PID: 820 (sshd)
Tasks: 1 (limit: 11510)
Memory: 4.6M
CGroup: /system.slice/sshd.service
└─820 /usr/sbin/sshd -D -oCiphers=aes256-gcm@openssh.com,chacha20-poly1305@openssh.com,aes256-ctr,aes256-cbc,aes128-gcm@openssh.com,aes128->
Dec 29 20:17:11 rhel8.local systemd[1]: Starting OpenSSH server daemon…
Dec 29 20:17:11 rhel8.local sshd[820]: Server listening on 0.0.0.0 port 22.
Dec 29 20:17:11 rhel8.local sshd[820]: Server listening on :: port 22.
Dec 29 20:17:11 rhel8.local systemd[1]: Started OpenSSH server daemon.
Dec 29 20:19:03 rhel8.local sshd[1499]: Accepted publickey for user from 192.168.122.1 port 35902 ssh2: RSA SHA256:b/8AoYgbThoBYPcFh7CetJuGY/Tl7s4fi>
Dec 29 20:19:03 rhel8.local sshd[1499]: pam_unix(sshd:session): session opened for user user by (uid=0)
Create Ansible inventory file, default is /etc/ansible/hosts
I like creating inventory file in my working directory.
$ vim inventory
Copy the IP address of your remote server(s) to manage and add to Ansible inventory file.
Save and Quit :wq!
$ echo "192.168.100.197" > inventory
You can also create a group of hosts like below:
[web] 192.168.100.197 [db] 192.168.100.198 [staging] 192.168.100.199 192.168.100.200 192.168.100.201
Generate SSH key and copy it to remote servers.
$ ssh-keygen $ ssh-copy-id user@192.168.100.197
Use ping module to test ansible:
$ ansible -i inventory 192.168.100.197 -m ping
192.168.100.197 | SUCCESS => {
"changed": false,
"ping": "pong"
}
The -i option is used to provide path to inventory file. You should get the same output for hosts group name.
$ ansible -i inventory web -m ping
192.168.100.197 | SUCCESS => {
"changed": false,
"ping": "pong"
}
For commands that need sudo, pass the option --ask-become-pass. This will ask for privilege escalation password. This may require installation of the sshpass program.
$ ansible -i inventory web -m command -a "sudo yum install vim" --ask-become-pass .... 192.168.100.197 | CHANGED | rc=0 >> Updating Subscription Management repositories. Updating Subscription Management repositories. Last metadata expiration check: 0:52:23 ago on Sat 25 Sep 2020 08:28:46 PM UTC. 2020-09-25 20:17:11 UTC Package vim-enhanced-2:8.0.1763-7.el8.x86_64 is already installed. Dependencies resolved. Nothing to do. Complete!
You now have Ansible installed on RHEL 8 / CentOS 8 server or Workstation. You can learn more on using Ansible to Manage your servers from Official Ansible documentation.