diff --git a/docs/usage.rst b/docs/usage.rst
index 965397024ef95fda8e058f507978241ae953fb40..b4f20d254a04db045f1577b1efc1a1eec76e9f3f 100644
--- a/docs/usage.rst
+++ b/docs/usage.rst
@@ -335,7 +335,15 @@ So, let's set this up for start:
         roles:
           - preseed
 
-2. Configure the role by creating the configuration file:
+2. Now we need to configure the role. Two parameters are mandatory -
+   one that specifies where the preseed files are to be stored, and
+   one that specifies the public key that should be used to
+   pre-populate the SSH authorized keys for the ``root`` account. This
+   is required for the initial bootstrap of servers because Debian
+   GNU/Linux does not by default allow the ``root`` user to
+   authenticate via SSH using a password. We will use the SSH public
+   key generated earlier via the ``ssh-keygen`` command. Create the
+   configuration file:
 
    :file:`~/mysite/group_vars/preseed.yml`
 
@@ -343,6 +351,9 @@ So, let's set this up for start:
 
       ---
 
+      # Public key used to authenticate remote logins via SSH for the
+      # root account.
+      ansible_key: "{{ lookup('file', '~/.ssh/id_rsa.pub') }}"
       # Directory where the preseed files will be output to.
       preseed_directory: "~/mysite/preseed_files/"
 
@@ -368,6 +379,9 @@ So, let's set this up for start:
 
       ---
 
+      # Public key used to authenticate remote logins via SSH for the
+      # root account.
+      ansible_key: "{{ lookup('file', '~/.ssh/id_rsa.pub') }}"
       # Directory where the preseed files will be output to.
       preseed_directory: "~/mysite/preseed_files/"
       # Set your default (initial) root password.