--- doc/build/ubuntu18LTS_install.frag	2021/03/16 01:07:42	1.5
+++ doc/build/ubuntu18LTS_install.frag	2022/03/26 19:00:51	1.7
@@ -93,6 +93,7 @@ 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
@@ -136,13 +137,29 @@ sudo apt-key add APT-GPG-KEY-loncapa.asc
 <p> Execute: </p>
 <pre>
 sudo apt-get install software-properties-common
-sudo apt-add-repository 'deb http://install.loncapa.org/ubuntu bionic main'
+sudo add-apt-repository 'deb http://install.loncapa.org/ubuntu bionic main'
 </pre>
 <p>
 You can display which repositories are currently enabled by using:
 </p>
 <pre>
-sudo apt-cache policy
+grep '^deb ' /etc/apt/sources.list |grep ' bionic '
+</pre>
+<p>The output should contain:</p>
+<pre>
+deb http://us.archive.ubuntu.com/ubuntu bionic main
+deb http://us.archive.ubuntu.com/ubuntu bionic universe
+deb http://install.loncapa.org/ubuntu bionic 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 to install 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>
@@ -180,7 +197,6 @@ execute the setup script with the follow
 <pre>
 cd installation
 sudo ./install.pl
-
 </pre>
 <p>
 The script is used to prepare a Linux system to run LON-CAPA, and can also be
@@ -253,7 +269,7 @@ for it to function at all.  Below is a l
 To configure and install LON-CAPA, execute the following commands:
 </p>
 <pre>
-cd loncapa-X.Y.Z     (X.Y.Z should correspond to a version number like '2.11.3')
+cd ../loncapa-X.Y.Z  (X.Y.Z should correspond to a version number like '2.11.3')
 sudo ./UPDATE
 </pre>
 <p>
@@ -278,7 +294,7 @@ cd
 <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>
 sudo /home/httpd/perl/loncontrol start