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How to Install Ansible on Ubuntu Linux

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The official Ansible installation instructions are WRONG, and will result in a bunch of errors and wasted time troubleshooting. Here’s how to install the newest version of Ansible on Ubuntu or Debian (or any other Linux distro, provided you swap out aptitude for your own package management commands).

Note:  This installs the NEWEST ‘stable’ version of Ansible, even if Ubuntu’s package repositories are outdated (which they usually are):

sudo -i
apt-get install pip
pip install --upgrade pip
pip install ansible jinja2 pyaml

Troubleshooting Failed Installs Because You Naiively Followed the Official Instructions

Here are the official installation docs, via https://docs.ansible.com/ansible/latest/intro_installation.html#latest-releases-via-pip

# Not really all you need to do
root@jenkins2:~# pip install ansible

First Error: Ansible doesn’t automatically pull in the required jinja2 module/package

Here’s what this looks like, after you run ‘pip install ansible’ as above:

jenkins@jenkins2:~$ ansible --version
Traceback (most recent call last):
 File "/usr/local/bin/ansible", line 40, in <module>
 import ansible.constants as C
 File "/usr/local/lib/python2.7/dist-packages/ansible/constants.py", line 12, in <module>
 from jinja2 import Template
ImportError: No module named jinja2

 

You get this error because ansible requires the jinja2 module, which isn’t marked as a required package in pip for some reason.

 

Solution: Install the missing jinja2 module via the jinja2 package in Pip

sudo pip install jinja2

 

Second Error: Pip doesn’t automatically pull in a yaml package for Ansible

This is the case if you’re getting an error like the following one:

jenkins@jenkins2:~$ ansible --version
Traceback (most recent call last):
 File "/usr/local/bin/ansible", line 40, in <module>
 import ansible.constants as C
 File "/usr/local/lib/python2.7/dist-packages/ansible/constants.py", line 18, in <module>
 from ansible.config.manager import ConfigManager, ensure_type, get_ini_config_value
 File "/usr/local/lib/python2.7/dist-packages/ansible/config/manager.py", line 11, in <module>
 import yaml

 

Solution: Install the yaml module via the pyaml package in Pip

sudo pip install pyaml

This is a stupidly named package in Pip — it’s easy to get the name wrong, as below. The solution is to just install the ‘pyaml’ package instead.

# ERROR: Install pyaml (it's not called yaml)
root@jenkins2:~# pip install yaml
Collecting yaml
 Could not find a version that satisfies the requirement yaml (from versions: )
No matching distribution found for yaml

 

So if you followed the instructions at the beginning of this post, OR you had to troubleshoot and start in the middle of this post somewhere, you should now have a functioning ansible install. If running ‘ansible –version’ doesn’t print out a version number, it should at least point you to the next error you need to troubleshoot.

Here’s an example from a Jenkins build server:

jenkins@jenkins-server:~$ ansible --version
ansible 2.4.2.0
 config file = /etc/ansible/ansible.cfg
 configured module search path = [u'/var/lib/jenkins/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
 ansible python module location = /usr/local/lib/python2.7/dist-packages/ansible
 executable location = /usr/local/bin/ansible
 python version = 2.7.12 (default, Nov 20 2017, 18:23:56) [GCC 5.4.0 20160609]

 

I hope that helps to guide you through the frustrating path of bad package naming, outdated repositories, and broken tooling that is (seemingly always) the current state of affairs in Ansible-land!

By the way, if you want to learn more about Linux, Programming, and other tech stuff, I’ve got a bunch of free Linux video tutorials up on my YouTube Channel: https://www.youtube.com/c/tutorialinux

Check it out!

The Hardest (and most fun) Problems to Troubleshoot

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I recently wrote a FAQ-style post about System Administration and technology careers in general. One of the best questions I was asked was about what kinds of really interesting troubleshooting problems I’ve had to deal with. Here’s that question, along with my answer:

What’s one of the most interesting things you’ve had to troubleshoot / do while maintaining a system?

I’m leaving out specific examples because they’re a mixture of non-public information and hyperspecific (uninteresting) technical stuff, but I can give some outlines for what generally makes for interesting problems to solve.

The really interesting problems I’ve seen tend to be related to performance, networking, and distributed systems. Usually they require a combination of different knowledge to solve:

  • Systems/OS: What is the operating system doing when everything slows down? What’s causing it to do that?
  • Networking/Distributed Systems: What’s actually happening when these machines communicate? How are they supposed to share and manage state, deal with network partitions, and ensure high availability? What are they *actually* doing when this problem happens?
  • Software Development: Which part of the code is causing this network/OS issue, and which code path leads there? Can I actually look at and modify this code? Is this code written by our developers, or an open-source project? What can I do to confirm the issue and test a fix? Can I contribute a fix back to the upstream project?