--- doc/build/ubuntu16LTS_install.frag	2017/06/12 20:56:13	1.2
+++ doc/build/ubuntu16LTS_install.frag	2022/03/26 19:00:51	1.7
@@ -56,7 +56,7 @@ DHCP is <em>not</em> supported.
 
 <h2>3. <a name="lin">Ubuntu 16.04 LTS installation</a></h2>
 <p>
-Installing Ubuntu Linux is easy.
+Installing Ubuntu Linux is straightforward.
 Documentation is available from
 <a href="https://help.ubuntu.com/community/Installation">https://help.ubuntu.com/community/Installation/</a>
 Most of the installation screens are self explanatory.
@@ -94,6 +94,7 @@ Use ufw to allow incoming traffic for th
 ssh, www, https
 </p>
 <pre>
+sudo apt-get install ufw
 sudo ufw default deny
 sudo ufw enable
 sudo ufw allow ssh
@@ -126,13 +127,6 @@ sudo apt-get upgrade
 <p>
 If kernel packages were updated, reboot your system before continuing with the installation.
 </p>
-<p>
-Add LON-CAPA ubuntu repository to your /etc/apt/sources.list file. 
-</p>
-<pre>
-sudo apt-get install python-software-properties
-sudo apt-add-repository 'deb http://install.loncapa.org/ubuntu xenial main'
-</pre>
 <h2>5. <a name="ilc">Installing LON-CAPA</a></h2>
 <h3>Import the LON-CAPA encryption key</h3>
 <pre>
@@ -140,6 +134,34 @@ wget http://install.loncapa.org/versions
 sudo apt-key add APT-GPG-KEY-loncapa.asc
 sudo apt-get update
 </pre>
+<h3>Add LON-CAPA ubuntu repository to /etc/apt/sources.list</h3>
+<p> Execute: </p>
+<pre>
+sudo apt-get install python-software-properties
+sudo add-apt-repository 'deb http://install.loncapa.org/ubuntu xenial main'
+</pre>
+<p>
+You can display which repositories are currently enabled by using:
+</p>
+<pre>
+grep '^deb ' /etc/apt/sources.list |grep ' xenial '
+</pre>
+<p>The output should contain:</p>
+<pre>
+deb http://us.archive.ubuntu.com/ubuntu xenial main
+deb http://us.archive.ubuntu.com/ubuntu xenial universe
+deb http://install.loncapa.org/ubuntu xenial main
+</pre>
+<p>If the Ubuntu universe repository is absent it can be added using:</p>
+<pre>
+sudo add-apt-repository universe
+</pre>
+<p>If other Ubuntu repositories, e.g., restricted and multiverse are enabled,
+you can disable them, as they are not needed for LON-CAPA, by using:</p>
+<pre>
+sudo add-apt-repository --remove restricted
+sudo add-apt-repository --remove multiverse
+</pre>
 <h3>Install prerequisites</h3>
 <p> Execute: </p>
 <pre>
@@ -147,12 +169,29 @@ sudo apt-get install loncapa-prerequisit
 </pre><p>
 This may take some minutes due to LON-CAPA's large number of dependencies.
 </p>
-<h3>Set MPM mode for Apache web server and enable use of cgi scripts</h3>
+<h3>Secure MySQL</h3>
+<p> Execute: </p>
+<pre>
+sudo mysql_secure_installation
+</pre><p>
+Press ENTER to skip set up of the validate password plugin.<br />
+In Ubuntu systems running MySQL 5.7 (and later), by default the MySQL root 
+user is authenticated by the auth_socket plugin which restricts root access
+to the local machine (and to sudo). If you prefer to set a password for the
+MySQL root user, you can do so, and user that instead of the default.
+</p><p>
+Answer “Y” (yes) to the prompts to: 
+(a) remove the anonymous user, 
+(b) restrict root user access to the local machine,
+and (c) remove the test database.</p>
+<h3>Set MPM mode for Apache web server and enable use of cgi scripts and webDAV</h3>
 <p>Execute: </p>
 <pre>
 sudo a2dismod mpm_event
 sudo a2enmod mpm_prefork
 sudo a2enmod cgi
+sudo a2enmod dav
+sudo a2enmod dav_fs
 </pre> 
 <h3>Retrieve and execute LON-CAPA setup program</h3>
 <p>
@@ -244,12 +283,11 @@ for it to function at all.  Below is a l
 
 <h3>Configuring LON-CAPA</h3>
 <p>
-To configure and install LON-CAPA, become root and execute the following commands:
+To configure and install LON-CAPA execute the following commands:
 </p>
 <pre>
-sudo -i
-cd /root/loncapa-X.Y.Z     (X.Y.Z should correspond to a version number like '2.12.0')
-./UPDATE
+cd ../loncapa-X.Y.Z  (X.Y.Z should correspond to a version number like '2.11.2')
+sudo ./UPDATE
 </pre>
 <p>
 You will need to enter the LON-CAPA configuration information you determined 
@@ -265,18 +303,19 @@ invoked below requires that you enter th
 Replace USERNAME and DOMAIN with an appropriate username and your domain.
 </p>
 <pre>
-cd /root/loncapa-X.Y.Z/loncom/build
-perl make_domain_coordinator.pl USERNAME DOMAIN
+cd loncom/build
+sudo perl make_domain_coordinator.pl USERNAME DOMAIN
+cd
 </pre>
 
 <h2>7. <a name="sts">Start/Restart Services</a></h2>
 <p>
 The LON-CAPA network services take a moment to start.  Most misconfigurations
-will be apparent at this step. Lastly, exit from root status to resume use of your regular account.
+will be apparent at this step.
 </p>
 <pre>
-/etc/init.d/loncontrol start
-/etc/init.d/apache2 restart
+sudo /etc/init.d/loncontrol start
+sudo service apache2 restart
 exit
 </pre>
 <p>