doc/cephadm: isolated environment and other deployment scenarios

This PR adds a section to the cephadm docs to describe how to install cephadm in different deployment scenarios (set cluster on single host, and deployment in an isolated environment or private network).

Signed-off-by: Melissa Li <melissali@redhat.com>
(cherry picked from commit a311e837d61f7677999eba7887b77d0752909834)

diff --git a/doc/cephadm/install.rst b/doc/cephadm/install.rst
index 269bdfbcad53240734bcd33039c99156276d06e9..b4f5c05eb81f0328b578b562890cfa601c32108a 100644 (file)
--- a/doc/cephadm/install.rst
+++ b/doc/cephadm/install.rst
@@ -231,6 +231,49 @@ available options.
 
 .. _cephadm-enable-cli:
 
+Different deployment scenarios
+==============================
+
+Single host
+-----------
+
+To configure a Ceph cluster to run on a single host, use the ``--single-host-defaults`` flag when bootstrapping.
+
+Deployment in an isolated environment
+-------------------------------------
+
+You can install Cephadm in an isolated environment by using a custom container registry and configuring Docker to use an insecure registry. Ensure your container image is inside the registry and that you have access to all hosts you wish to add to the cluster. Currently, to add multiple hosts to a Ceph cluster in an isolated environment, you must use Docker. This may require you to uninstall Podman if it's present on your host as Cephadm prefers to use Podman over Docker.
+
+Run a local container registry:
+
+.. prompt:: bash #
+
+   docker run --privileged -d --name registry -p 5000:5000 -v /var/lib/registry:/var/lib/registry --restart=always registry:2
+
+Edit the ``/etc/docker/daemon.json`` file with the hostname and port where the registry is running:
+
+.. code-block:: bash
+
+   { "insecure-registries":["*<hostname>*:5000"] }
+
+.. note:: For every host which accesses the local registry, you will need to repeat this step and edit the ``/etc/docker/daemon.json`` file on the host.
+
+Restart docker:
+
+.. prompt:: bash #
+
+   systemctl daemon-reload
+   systemctl restart docker
+   
+Next, push your container image to your local registry.
+
+Then run bootstrap using the ``--image`` flag with your container image. For example:
+
+.. prompt:: bash #
+
+   cephadm --image *<hostname>*:5000/ceph/ceph bootstrap --mon-ip *<mon-ip>*
+
+
 Enable Ceph CLI
 ===============