cephadm-ansible

Automate deploying Ceph at scale using cephadm and Ansible

NOTE: This has basically reached the point of gross scaffolding
that kind of works. Don’t run this and expect anything positive to
happen, especially not in a production environment.

cephadm-ansible is an Ansible playbook that deploys Ceph by
automating the use of the new cephadm script. The intention is to
explore creating an alternative to ceph-ansible that more closely
aligns with the needs and deployment strategy employed by
kolla-ansible. This playbook will allow a user to deploy a
standalone Ceph cluster that trivializes integrating with
kolla-ansible, and follows official Ceph recommended practices by
default.

If you are new to Ceph, please see the following:

• https://docs.ceph.com/en/octopus/start/hardware-recommendations/
• https://docs.ceph.com/en/octopus/start/os-recommendations/
• https://docs.ceph.com/en/octopus/cephadm/

Goals

• Deploying must be relatively trivial, with clear directions
• Deploying and Updating in the same Ceph release must be boring
• Purging a cluster must revert all changes, with no side effects
• Upgrading to a newer Ceph release must be seemless
• All of the above must also work flawlessly with kolla-ansible

Usage

This section covers how to use this process, outlining how to setup,
configure, deploy/update, and

Setup

$ git clone https://github.com/jcmdln/cephadm-ansible
$ cd cephadm-ansible
$ virtualenv venv
$ . venv/bin/activate
(venv) $ pip install -r requirements.txt

Configure

1. Create your inventory

   Make a copy of sample.inventory.yml:

    $ cp {sample.,}inventory.yml

   Read over the created inventory.yml and add your hosts as outlined
   in the comments above each defined group.

2. Define your configuration

   Make a copy of group_vars/sample.all.yml:

    $ cp group_vars/{sample.,}all.yml

   Read over the created group_vars/all.yml and adjust the variables
   as outlined in the comments in each section.

Deploying / Updating

The process of deploying a Ceph cluster as well as updating it
within the same release are the same process.

1. (Optional) Fetch the latest commits from the current branch

    $ git pull origin master

2. Run the playbook

    $ ansible-playbook -i inventory.yml site.yml

Currently this process is not foolproof because a baseline of stability
from which to automate changes has not yet been defined. Consider the
above to probably work, and expect to roll up your sleeves and have to
do some work.

Purging

Destroying a Ceph cluster requires using cephadm rm-cluster and is
not handled automatically by this playbook. The mentioned command does
simplify the process and handles everything, so there’s no real need
for additional logic to be added to this playbook.