sync with previous repo

docs/ansible.md

@@ -0,0 +1,73 @@
+
+# Running this playbook
+
+This playbook is meant to be run using [Ansible](https://www.ansible.com/).
+
+Ansible typically runs on your local computer and carries out tasks on a remote server.
+If your local computer cannot run Ansible, you can also run Ansible on some server somewhere (including the server you wish to install to).
+
+
+## Supported Ansible versions
+
+Ansible 2.7.1 or newer is required ([last discussion about Ansible versions](https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/743)).
+
+Note: Ubuntu 20.04 ships with Ansible 2.9.6 which is a buggy version (see this [bug](https://bugs.launchpad.net/ubuntu/+source/ansible/+bug/1880359)), which can't be used in combination with a host running new systemd (more details in [#517](https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/517), [#669](https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/669)). If this problem affects you, you can: avoid running Ubuntu 20.04 on your host; run Ansible from another machine targeting your host; or try to upgrade to a newer Ansible version (see below).
+
+
+## Checking your Ansible version
+
+In most cases, you won't need to worry about the Ansible version.
+The playbook will try to detect it and tell you if you're on an unsupported version.
+
+To manually check which version of Ansible you're on, run: `ansible --version`.
+
+If you're on an old version of Ansible, you should [upgrade Ansible to a newer version](#upgrading-ansible) or [use Ansible via Docker](#using-ansible-via-docker).
+
+
+## Upgrading Ansible
+
+Depending on your distribution, you may be able to upgrade Ansible in a few different ways:
+
+- by using an additional repository (PPA, etc.), which provides newer Ansible versions. See instructions for [CentOS](https://docs.ansible.com/ansible/latest/installation_guide/intro_installation.html#installing-ansible-on-rhel-centos-or-fedora), [Debian](https://docs.ansible.com/ansible/latest/installation_guide/intro_installation.html#installing-ansible-on-debian), or [Ubuntu](https://docs.ansible.com/ansible/latest/installation_guide/intro_installation.html#installing-ansible-on-ubuntu) on the Ansible website.
+
+- by removing the Ansible package (`yum remove ansible` or `apt-get remove ansible`) and installing via [pip](https://pip.pypa.io/en/stable/installing/) (`pip install ansible`).
+
+If using the `pip` method, do note that the `ansible-playbook` binary may not be on the `$PATH` (https://linuxconfig.org/linux-path-environment-variable), but in some more special location like `/usr/local/bin/ansible-playbook`. You may need to invoke it using the full path.
+
+
+**Note**: Both of the above methods are a bad way to run system software such as Ansible.
+If you find yourself needing to resort to such hacks, please consider reporting a bug to your distribution and/or switching to a sane distribution, which provides up-to-date software.
+
+
+## Using Ansible via Docker
+
+Alternatively, you can run Ansible on your computer from inside a Docker container (powered by the [devture/ansible](https://hub.docker.com/r/devture/ansible/) Docker image).
+
+Here's a sample command to get you started (run this from the playbook's directory):
+
+```bash
+docker run -it --rm \
+-w /work \
+-v `pwd`:/work \
+-v $HOME/.ssh/id_rsa:/root/.ssh/id_rsa:ro \
+--entrypoint=/bin/sh \
+docker.io/devture/ansible:2.9.14-r0
+```
+
+The above command tries to mount an SSH key (`$HOME/.ssh/id_rsa`) into the container (at `/root/.ssh/id_rsa`).
+If your SSH key is at a different path (not in `$HOME/.ssh/id_rsa`), adjust that part.
+
+Once you execute the above command, you'll be dropped into a `/work` directory inside a Docker container.
+The `/work` directory contains the playbook's code.
+
+You can execute `ansible-playbook` commands as per normal now.
+
+### If you don't use SSH keys for authentication
+
+If you don't use SSH keys for authentication, simply remove that whole line (`-v $HOME/.ssh/id_rsa:/root/.ssh/id_rsa:ro`).
+To authenticate at your server using a password, you need to add a package. So, when you are in the shell of the ansible docker container (the previously used `docker run -it ...` command), run:
+```bash
+apk add sshpass
+```
+Then, to be asked for the password whenever running an  `ansible-playbook` command add `--ask-pass` to the arguments of the command.
+