Installation Manual for 2.18 on Ubuntu

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These instructions cover the installation of WeBWorK 2.18 for Ubuntu Server 22.04 LTS.

Other installation methods (which are faster and easier) include using the WeBWorK Virtual Machine Image (see Installing WeBWorK from a Virtual Machine Image) which has been tested on VMware, VirtualBox and QEMU/KVM and using the WeBWorK AMI if you want to run your server on AWS (see WeBWorK Amazon Machine Images (AMI's)).


If you are just upgrading WeBWorK, especially if you already have existing WeBWorK courses, see Upgrading_WeBWorK_from_2.17_to_2.18.

Contents

Notation

First some short comments on notation we will be using. We will use <key> to indicate that you should press a specific key (e.g. <Enter>, <Tab>, <F12>, etc.). Sometimes we will also use e.g. <wwadmin password> to indicate you have to enter the wwadmin password. Note that we will use wwadmin to refer to your administrative user on the system. In practice you should NOT actually use wwadmin for your administrative user name. Using a fixed user name that is publicly known is a severe security vulnerability.

^ will indicate the <Ctrl> key so e.g. ^X is really shorthand for <Ctrl> <X>, i.e. press the Ctrl key and hit the X key.

Code blocks begin with $. You are not intended to type the $ character as part of the provided commands. Note that many commands begin with sudo. These commands are executed with super user privileges. You will need to enter your password for the first invocation of one of these commands which will begin a super user session. That session will timeout typically 15 minutes after the last entered sudo command. You can also enter a super user shell with sudo -s. However, it is not advisable to do so. This is an unsafe practice. Forgetting to exit the super user shell is a common mistake that can lead to disastrous consequences if the wrong command is executed with the elevated privileges.

Installing the Ubuntu 22.04 Server Operating System

Installation

Connect to http://www.ubuntu.com/ for information. We recommend you use the "Long Term Support" (LTS) version of Ubuntu which is currently version 22.04. The next LTS release will be version 24.04 to be released in April, 2024.

The installation process consists of a series of steps or panels. In the panels, generally you will use <Tab> or the up and down arrows to navigate, the <Space> bar to check a box and the <Enter> key to confirm an action. On the "Chose type of install" panel, select the default "Ubuntu Server", not the "Ubuntu Server (minimized)"

Enter the information for the steps until you get to the "Profile setup".

Profile Setup

What you fill in for the "Profile setup" is a privileged user so you might want to enter a special administrative account rather than your normal account. We suggest wwadmin but you can use whatever you want.

  • Enter the information for "Your name"
  • Enter the information for "Your Computer's name"
  • Enter the information for "Pick a username" In these instructions, we will call this name wwadmin.
  • Enter the information twice for the password. In these instructions, we will call this password the <wwadmin password>. DO NOT FORGET WHAT YOU ENTER HERE.
  • Then select Done and press <Enter>.


SSH Setup
Select "Install OpenSSH server". Then select Done and press <Enter>.
Featured Server Snaps
Do not select any server snaps. Then select Done and press <Enter>.


Now sit back and relax while the installation takes place. This should be pretty quick. When you finally see "Reboot Now", press <Enter> and log into your server.

Accessing Your Server Remotely

At this point you can login your server from a remote location using SSH (non secure telnet and FTP are not allowed but secure SSH and SFTP are).

You can do all of the remaining installation from a remote location if you wish. The advantage of doing this is that you can copy commands from these instructions (with copy from the Edit menu or ^C) and paste them into a terminal window (with paste from the Edit menu list or <Shift> <Ctrl> <V> or <Shift> <Insert> depending on your application). This is an excellent way to use these instructions since it is fast and insures commands are entered correctly (just be careful to read before you run the command and replace things like database_password with the correct code in the few places such things occur).

Assuming your network has been set up, type 

$ ip addr show

and you will see something like 

...
link/ether 00:0c:29:4f:2c:1d brd ff:ff:ff:ff:ff:ff
inet 192.168.76.128/24 brd 192.168.76.255 scope global dynamic ens33
...

Here 192.168.76.128 is the ip address of your server. Note that you should ignore the loopback address 127.0.0.1.

Install Software Packages

Ubuntu Software Packages

On Ubuntu and other Debian linuxes, the following instructions will get needed software packages installed. You may first have to run the commands 

$ sudo apt update
$ sudo apt upgrade

to update package locations and upgrade. Restart all services if requested.

Here is the list of Ubuntu packages that need to be installed.

  1. apache2
  2. cpanminus
  3. curl
  4. dvipng
  5. dvisvgm
  6. gcc
  7. git
  8. imagemagick
  9. libarchive-zip-perl
  10. libarray-utils-perl
  11. libcrypt-ssleay-perl
  12. libdata-dump-perl
  13. libdata-structure-utils-perl
  14. libdatetime-perl
  15. libemail-address-xs-perl
  16. libemail-sender-perl
  17. libemail-stuffer-perl
  18. libexception-class-perl
  19. libextutils-xsbuilder-perl
  20. libfile-find-rule-perl-perl
  21. libfile-sharedir-install-perl
  22. libfuture-asyncawait-perl
  23. libgd-perl
  24. libhttp-async-perl
  25. libiterator-perl
  26. libiterator-util-perl
  27. libjson-perl
  28. liblocale-maketext-lexicon-perl
  29. libmime-tools-perl
  30. libmojolicious-perl
  31. libnet-ip-perl
  32. libnet-ldap-perl
  33. libnet-oauth-perl
  34. libossp-uuid-perl
  35. libpadwalker-perl
  36. libpath-class-perl
  37. libphp-serialization-perl
  38. libpod-wsdl-perl
  39. libsoap-lite-perl
  40. libsql-abstract-perl
  41. libsql-abstract-classic-perl
  42. libstring-shellquote-perl
  43. libsvg-perl
  44. libtemplate-perl
  45. libtest-exception-perl
  46. libtest-fatal-perl
  47. libtest-mockobject-perl
  48. libtest-requires-perl
  49. libtest-warn-perl
  50. libtext-csv-perl
  51. libtimedate-perl
  52. libtype-tiny-perl
  53. libuniversal-can-perl
  54. libuniversal-isa-perl
  55. libuuid-tiny-perl
  56. libxml-parser-easytree-perl
  57. libxml-parser-perl
  58. libxml-writer-perl
  59. libyaml-libyaml-perl
  60. make
  61. netpbm
  62. npm
  63. openssh-server
  64. pdf2svg
  65. preview-latex-style
  66. texlive
  67. texlive-latex-extra
  68. unzip

To install all of these packages in one fell swoop run the command (obviously you want to use cut and paste) 

$ sudo apt install apache2 cpanminus curl dvipng dvisvgm gcc git imagemagick libarchive-zip-perl \
libarray-utils-perl libcrypt-ssleay-perl libdata-dump-perl libdata-structure-util-perl \
libdatetime-perl libemail-address-xs-perl libemail-sender-perl libemail-stuffer-perl \
libexception-class-perl libextutils-xsbuilder-perl libfile-find-rule-perl-perl \
libfile-sharedir-install-perl libfuture-asyncawait-perl libgd-perl libhttp-async-perl \
libiterator-perl libiterator-util-perl libjson-perl liblocale-maketext-lexicon-perl \
libmime-tools-perl libmojolicious-perl libnet-ip-perl libnet-ldap-perl libnet-oauth-perl \
libossp-uuid-perl libpath-class-perl libphp-serialization-perl libpod-wsdl-perl libsoap-lite-perl \
libsql-abstract-classic-perl libsql-abstract-perl libstring-shellquote-perl libsvg-perl \
libtemplate-perl libtest-exception-perl libtest-fatal-perl libtest-mockobject-perl \
libtest-requires-perl libtest-warn-perl libtext-csv-perl libtimedate-perl libtype-tiny-perl \
libuniversal-can-perl libuniversal-isa-perl libuuid-tiny-perl libxml-parser-easytree-perl \
libxml-parser-perl libxml-writer-perl libyaml-libyaml-perl make netpbm npm openssh-server pdf2svg \
preview-latex-style texlive texlive-latex-extra unzip

Accept any prompts with the default answer by hitting <Enter>. Restart all services if requested.

Installation of Other Perl Modules with cpanm

We will use cpanm to install other perl modules that are not available as Ubuntu packages. For example, one module, Statistics::R::IO that will be needed is not in a standard package. We also need Mojolicious::Plugin::NotYAMLConfig. To install these 

$ sudo cpanm Statistics::R::IO Mojolicious::Plugin::NotYAMLConfig
[sudo] password for wwadmin: <wwadmin password>

Below, we will determine other perl modules that will need to be installed with this method.

Setting up Apache2

This sets up some helpful modules for apache and tests to make sure that apache is up and running. These modules are useful but not necessary.

enabling info.conf and status.conf in Ubuntu

We enable the info module. Acting as root in a terminal window enter 

$ sudo a2enmod info

Next we make a copy of the configuration files we will be editing for safekeeping. 

$ cd /etc/apache2/mods-available

$ sudo cp info.conf info.conf.bak1
$ sudo cp status.conf status.conf.bak1

Now we will edit configuration files info.conf and status.conf to allow us to view information about the setup and performance of the web server. Note that this is not absolutely necessary but it can be very useful. You can use your favorite editor but we will give instructions assuming you are using nano. Note that you have to be root to edit these files. First we edit info.conf 

$ cd /etc/apache2/mods-available
$ sudo nano info.conf

I suggest you allow access to server information from e.g. your department domain. To do this un-comment (i.e. remove the # from) 

	Require ip 192.0.2.0/24

and then replace Require ip 192.0.2.0/24 by Require host math.yourschool.edu (or Require host yourschool.edu if you want to allow wider access) where of course you should edit math.yourschool.edu appropriately. You could also use a specific or range of ip addresses following the syntax in the example.


Then save the file and quit (press ^X, Y, <Enter>).

Now we edit status.conf 

$ cd /etc/apache2/mods-available
$ sudo nano status.conf

Edit the 

 #Require ip 192.0.2.0/24

line just as you did for info.conf. Then save the file and quit. And restart Apache so that the above changes take effect 

$ sudo systemctl restart apache2

Fully Qualified Domain Name

Now we have to set your server's fully qualified domain name. Note that if your network was set up automatically via DHCP, your server's fully qualified domain name should already be set up. You can check by running the hostname commands below.

Run the command 

sudo hostnamectl set-hostname webwork

where of course you should replace webwork by whatever your server's name is.

You can check these settings by running the commands 

$ hostname --fqdn

and 

$ hostname

The first gives the server's fully qualified domain name (e.g. webwork.mydepartment.myschool.edu) and the second the server's name (e.g. webwork).

Note that if your server can not find its fully qualified domain name, certain tools (such as the Synaptic Package Manager) may not start.

Test Apache

Now restart Apache 

$ sudo systemctl restart apache2

and test your server by connecting to your server ("http://yourserver.yourschool.edu") from a browser on a remote machine. You should see the Apache2 Ubuntu Default Page indicating that Apache is running.

You can check Apache's status by connecting to "http://yourserver.yourschool.edu/server-status" from a browser on a remote machine in the math.yourschool.edu domain.

Further test Apache by connecting to "http://yourserver.yourschool.edu/server-info" from a browser on a remote machine in the math.yourschool.edu domain and you will see a page listing various information about Apache. In particular under Server Settings you should see 

Server Version: Apache/2.4.52 (Ubuntu) mod_apreq2-20090110/2.8.0 mod_perl/2.0.12 Perl/v5.34.0

(or something very similar) indicating that both mod_apreq2 and mod_perl are installed.

If you have problems now or in the future, a good first thing to do is to look at the Apache error log which is located at /var/log/apache2/error.log. In the directory /var/log/apache2/ you can "less" through the error log (less error.log), look at the last few entries (tail error.log) or run the command tail -f error.log which will display new error messages as they are appended to the file. To quit less and go back to the command line press q and use ^C to break out of tail -f . For example if you didn't set up access to "server-info", you can run 

$ tail /var/log/apache2/error.log

and in the output you should see something similar to 

...[mpm_event:notice] [pid 35885:tid 139917041878912] AH00489: Apache/2.4.52 (Ubuntu) mod_apreq2-20090110/2.8.0 mod_perl/2.0.12 Perl/v5.34.0 configured -- resuming normal operations

indicating that both mod_apreq2 and mod_perl are installed and running.

Installing a Database

This section installs MariaDB as the database manger for webwork. MariaDB is the recommended database but you can install and use MySQL if you wish.

Installing and Testing MariaDB

Install MariaDB using the distribution and cpan packages. 

$ sudo apt install mariadb-server libmariadb3 libmariadb-dev
$ sudo cpanm DBD::MariaDB

Restart all services if requested.

Securing the Database

Then we should secure the server. Note that if you install MariaDB as we suggest, all mysql commands automatically use the MariaDB. 

$ sudo mysql_secure_installation

To get started just hit <Enter> since there is no password set for root. You should answer n to the first two questions as is suggested and answer Y to all the remaining questions.

Now test that all is well: 

$ sudo mysql

You should see 

Welcome to the MariaDB monitor ...
MariaDB>

Now lets check the MariaDB users. To see the users, do the following 

 MariaDB> SELECT user,authentication_string,plugin,host FROM mysql.user;

You will see a table with only three users: mariadb.sys, root and mysql.

Now exit MariaDB 

MariaDB> exit
Bye
$

Downloading the WeBWorK System Software and Problem Libraries

We are finally at the point where we can start downloading and installing WeBWorK. We will use Git to download WeBWorK from Github. This is easy and it will also make it easy to update the system in the future. Note that the following are rather long commands; it is much easier to copy (^C) them from this document and paste (<Shift> <Ctrl> <V> or <Shift> <Insert>) them in a terminal window 

$ cd
$ mkdir downloads
$ cd downloads
$ git clone https://github.com/openwebwork/webwork2.git
$ git clone https://github.com/openwebwork/pg.git
$ git clone https://github.com/openwebwork/webwork-open-problem-library.git

Important Note. The above commands retrieve the main branch which gives the latest stable release of the software package (webwork2, pg, etc.) with bug fixes. If a stable release newer than 2.18 exists, that will be downloaded and these instructions may be a little out of date. So it is a good idea to check before downloading. The best way to do that is to look at https://github.com/openwebwork/webwork2/blob/main/VERSION and https://github.com/openwebwork/pg/blob/main/VERSION.

The first and second download gives you the latest released versions of WeBWorK 2 and PG. The third download contains the WeBWorK Open Problem Library (OPL) which contains thousands of WeBWorK problems (over 37,000 currently).

The main information page about WebWorK downloads is available at http://webwork.maa.org/wiki/Category:Release_Notes

The main information page about the OPL is available at http://webwork.maa.org/wiki/Open_Problem_Library

Installing WeBWorK

Note the instructions below assume you are installing WeBWorK from scratch. If you are just upgrading WeBWorK, especially if you already have existing WeBWorK courses, see Upgrading_WeBWorK_from_2.17_to_2.18.

Move the System into the Required Directories

As root create a webwork directory under /opt, change the ownership of the webwork directory to www-data, which is what the apache server runs as and move directories there. 

$ cd
$ cd downloads
$ sudo mkdir /opt/webwork
[sudo] password for wwadmin: <wwadmin password>
$ sudo chown www-data:www-data /opt/webwork
$ sudo mv webwork2 /opt/webwork/
$ sudo mv pg /opt/webwork/

Now create the courses and libraries directories under webwork and copy and move content there 

$ sudo mkdir /opt/webwork/courses
$ sudo mkdir /opt/webwork/libraries
$ sudo mv webwork-open-problem-library /opt/webwork/libraries/
$ cd /opt/webwork/webwork2/courses.dist
$ sudo cp *.lst /opt/webwork/courses/
$ sudo rsync -a modelCourse /opt/webwork/courses/

Setting Permissions

The PG installation directory and files should be owned by www-data and not writable by other users: 

$ sudo chmod -R u+rw,go+r /opt/webwork/pg

Most WeBWorK directories and files should also be owned by www-data and not writable by other users: 

$ sudo chmod -R u+rw,go+r /opt/webwork/webwork2

Certain data directories need to be writable by the web server. These are DATA, courses, htdocs/tmp, logs, and tmp. It is convenient to give WeBWorK administrators access to these directories as well, so they can perform administrative tasks such as removing temporary files, creating and editing courses from the command line, managing logs, and so on. We will use the default group for web services www-data.

It is helpful for the user administering webwork to be in this group. As above we are calling this user wwadmin. To add wwadmin to the www-data group, 

$ sudo adduser wwadmin www-data

where of course you should replace wwadmin by the actual user name. You can check that this succeeded by runing 

$ id wwadmin

and then you should see www-data listed under groups.

Now we make the WeBWorK directories that need to be writable by the web server have www-data as their group. The following are rather long commands; you might want to copy them and paste them into your terminal window rather than typing them. 

$ cd /opt/webwork/webwork2/
$ sudo chgrp -R www-data DATA ../courses htdocs/tmp logs tmp
$ sudo chmod -R g+w DATA ../courses htdocs/tmp logs tmp

Configuring the Shell

To make working with WeBWorK easier, there are a couple of changes you can make to your shell environment.

Add the WeBWorK bin directory to your path. This will allow you to run WeBWorK command-line utilities without typing the full path to the utility. Go to your home directory and backup your .bashrc file 

$ cd
$ cp .bashrc .bashrc.bak1

Now edit .bashrc 

$ nano .bashrc

After the last line add the three lines: 

export PATH=$PATH:/opt/webwork/webwork2/bin
export WEBWORK_ROOT=/opt/webwork/webwork2
export PG_ROOT=/opt/webwork/pg

Then save the file and Quit.

Close your Terminal Window and open a new one so the above changes take effect. You can check that they have by 

$ echo $PATH
$ echo $WEBWORK_ROOT
$ echo $PG_ROOT

Install node and npm

WW 2.17 requires newer versions of node and npm than are in the Ubuntu repositories.

Note that if you have a previous version of node installed, then you will need to first uninstall it. To determine if this is the case run 

$ node --version

If that shows v16.??.? then you already have node 16 installed. If that says Command 'none' not found, ..., then skip to installing node below. If a version is shown that does not start with 16, then uninstall node with the commands: 

$ sudo apt autoremove nodejs nodejs-doc
$ sudo rm /etc/apt/sources.list.d/nodesource.list
$ sudo apt update

Run the following commands to install node version 16 and npm version 8 from nodesource: 

$ curl -fsSL https://deb.nodesource.com/setup_16.x | sudo -E bash -
$ sudo apt install -y nodejs

Checking Module Dependencies

WeBWorK includes a script called check_modules.pl (in the directory /opt/webwork/webwork2/bin) that verifies that the needed programs and Perl modules are installed on your system. Run this script to make sure you have installed the required programs and Perl modules. 

$ check_modules.pl

Scroll up and look through the listing. It should find everything. If something is missing (flagged by **), look back through these instructions to find where it should have been installed and install it.

Obtaining Javascript Libraries

Javascript libraries are now obtained using npm. This includes the following javascript packages:

  1. codemirror
  2. bootstrap
  3. flatpickr
  4. fontawesome
  5. iframe-resizer
  6. jquery
  7. jquery-ui
  8. mathjax
  9. sortablejs
  10. jsxgraph
  11. mathquill

Furthermore, all local javascript and css files are minimized, and the generated file names include a hash of the content. This ensures that browser's always are served up to date files when these files change, and prevent the need for users to need to refresh their browser cache.

To install all javascript dependencies and minimize local javascript and css: 

$ cd /opt/webwork/webwork2/htdocs/
$ npm install
$ cd /opt/webwork/pg/htdocs/
$ npm install

Optionally, if you do not wish to serve third party javascript libraries, you may instead choose to have the files served from a CDN. To make this happen instead use: 

$ cd /opt/webwork/webwork2/htdocs/
$ USE_CDN=1 npm install
$ cd /opt/webwork/pg/htdocs/
$ USE_CDN=1 npm install

Checking LaTeX packages

Now we check that all necessary LaTeX packages have been installed. Run the command 

$ check_latex

and look for missing packages (you can ignore "No file check_latex.aux."). If the script displays "Compilation Success!", then all is good!

Miscellaneous System Patches

If the users of your system will be using problems that utilize the new PGtikz.pl macro then you will need to apply the following patch: 

$ sudo patch -p1 -d / < /opt/webwork/webwork2/docker-config/imagemagick-allow-pdf-read.patch

Configuring WeBWorK

Making Copies of the Distribution Configuration Files

Before configuring the system, you must make local copies of the site.conf and localOverrides.conf configuration files, located in /opt/webwork/webwork2/conf/ . 

$ cd /opt/webwork/webwork2/conf
$ cp site.conf.dist site.conf
$ cp localOverrides.conf.dist localOverrides.conf

WeBWorK System Configuration

Most WeBWorK configuration is done in the files /opt/webwork/webwork2/conf/site.conf and /opt/webwork/webwork2/conf/localOverrides.conf. These files provide system-wide configuration settings, and defaults for course settings. Any setting in these files can be overridden in the course.conf file for a particular course. To override a setting for a course, just put the new setting (using the same syntax as is in localOverrides.conf) in the course.conf file. An instructor can only edit the course.conf file herself (for her own course) if she has "admin" privilege which by default instructors do not have. But most things instructors may want to customize and many others (language, timezone, permissions, display modes, email, ...) can be set using the Course Configuration page from within the course and such setting override those in the configuration files.

Actually there are three main configuration files, site.conf, defaults.config and localOverrides.conf. The reason there are three configuration files is to make upgrading WeBWorK easier.

  • site.conf: This file contains global variables which are required for basic configuration. It will not be overridden when you update WeBWorK but its distribution version, site.conf.dist will be.
  • defaults.config: This file contains initial settings for many customizable options in WeBWorK. Do not edit defaults.config. It will be overridden next time you upgrade.
  • localOverrides.conf This is where you should add all local customizations. It will not be overridden when you update WeBWorK but its distribution version, localOverrides.conf.dist will be.

There are several options that must be set for WeBWorK to work with your system. The rest of the file consists of customization options.

Edit the site.conf file

Now edit site.conf 

$ nano /opt/webwork/webwork2/conf/site.conf

First we have to add information about the Apache2 server setup. Search for server_root_url and edit the line so that it reads: 

$server_root_url   = 'http://yourserver.yourschool.edu';

where of course you should edit yourserver.yourschool.edu appropriately. The "http://" is important. If you are running a secure server (i.e., using SSL - really TLS), the url should start with https: but you should wait to make that change until after WeBWorK is up and running and you set up SSL. In that case the "https://" is important.

Database Settings

Search for the code $database_driver. By default the $database_driver is set to MariaDB which is correct unless you installed MySQL. If you installed MySQL, uncomment the MySQL line and comment out the MarisDB line.

We need to set a password that WeBWorK uses when it communicates with the MySQL database. Note that this is not the same as the <mysql root password> which is the unused password we set when securing MySQL. Search for database_password and replace the line 

$database_password = "passwordRW";

by 

$database_password = 'database_password';

where of course you should replace "database_password" with your own password but do use the single quotes. Remember this password as we will need it below.

WeBWorK sends mail in three instances. The PG system sends mail to report answers to questionnaires and free-response problems. The mail merge module is used to send mail to course participants, i.e. to report scores. The feedback module allows participants to send mail to course instructors.

To send mail, WeBWorK needs the address of an SMTP server. Normally you will use the address of your school's SMTP server. If the local machine is running an SMTP server, use localhost. IMPORTANT: Our instructions above did not install an SMTP server so you will have to install and configure one if you do not use your school's SMTP server. When connecting to the SMTP server, WeBWorK must also send an email address representing the sender of the email (this has nothing to do with the From address on the mail message). Edit the lines 

$mail{smtpServer} = ;  # e.g. 'mail.yourschool.edu' or 'localhost'
$mail{smtpSender} = ;  # e.g.  'webwork@yourserver.yourschool.edu'

entering the appropriate information. Be sure to use single quotes and NOT double quotes around email addresses otherwise Perl will treat @ as an array variable.

WeBWorK uses the DateTime module. DateTime is supposed to be able to determine the local timezone itself without you having to enter it but this often fails so it is best to just set it here. For a list of timezones recognized by DateTime run the command 

timedatectl list-timezones

These timezones are more refined than standard time zone usage in that they include switches to daylight savings time (e.g. some parts of a time zone may make the switch and others may not). For example if your server is in the eastern US, on the list you will see America/New_York and you should enter $siteDefaults{timezone} = "America/New_York"; which is the default. Read the documentation in this section of the the site.conf file for more information on selecting time zones and formatting dates.

Search for $siteDefaults{timezone} and enter your local timezone if it is not correct.

Then save the file and Quit.

Custom Themes

If you would like to customize the appearance of WeBWorK, then see Customizing WeBWorK.

Default Header Files

After you have used WeBWorK for awhile, you may want to change the default header files in defaults.config. Search for $webworkFiles{screenSnippets}{setHeader} and $webworkFiles{hardcopySnippets}{setHeader} in localOverrides.config. Settings in the conf and config files affect all WeBWorK courses. You can override any setting in these conf and config files for an individual course by putting the local setting in course.conf.

Set up the webwork database

WeBWorK uses a single database, called webwork, for all courses. We will create the webwork database now.

To do this do the following (before you just copy, paste and hit <Enter> notice that you have to replace database_password with the password you set when editing site.conf above): 

$ sudo mysql 
[sudo] password for wwadmin: <wwadmin password>

MariaDB > CREATE DATABASE webwork;
MariaDB > CREATE USER 'webworkWrite'@'localhost' IDENTIFIED BY 'database_password';
MariaDB > GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, ALTER, DROP, LOCK TABLES ON webwork.* TO 'webworkWrite'@'localhost';
MariaDB > exit
Bye
$

where as we said replace database_password with the password you set when editing site.conf above.

Configuring Apache

WeBWorK ships with an Apache config file that needs to linked into your Apache configuration process. The file is named webwork.apache2.4-config.dist and located in the conf directory. First, copy the file to webwork.apache2-config: 

$ cd /opt/webwork/webwork2/conf
$ cp webwork.apache2.4-config.dist webwork.apache2.4-config

and now link it into your Apache configuration process 

$ sudo ln -s /opt/webwork/webwork2/conf/webwork.apache2.4-config /etc/apache2/conf-enabled/webwork.conf

The default multi-processing module (MPM) for Apache is the event module but WeBWorK uses the prefork module. So we disable the event module and enable the prefork module. 

$ sudo a2dismod mpm_event
$ sudo a2enmod mpm_prefork

WeBWorK requires the Apache 2 rewrite module to be enabled for serving files in the pg/htdocs location. 

$ sudo a2enmod rewrite

Next we will make a few changes to Apache's default configuration. We need to edit two files. First we will save copies of the original files. 

$ sudo -s
# cd /etc/apache2/
# cp apache2.conf apache2.conf.bak1
# cd /etc/apache2/mods-available/
# cp mpm_prefork.conf mpm_prefork.conf.bak1
# exit

Edit apache2.conf

$ sudo nano /etc/apache2/apache2.conf

Search for the line 

Timeout 300

and replace it by 

Timeout 1200

Then save the file and quit.

Edit mpm_prefork.conf

$ cd /etc/apache2/mods-available/
$ sudo nano mpm_prefork.conf

Search for the lines 

    MaxRequestWorkers        150
    MaxConnectionsPerChild   0

Which occur under <IfModule mpm_prefork_module> and replace them by 

# For WeBWorK a rough rule of thumb is 5 MaxRequestWorkers per 1 GB of memory
      MaxRequestWorkers        10
      MaxConnectionsPerChild   50

where you should set MaxRequestWorkers depending on the amount of memory your server has using the above rule of thumb. Note that for very busy servers, you should observe you memory usage and adjust the above settings as necessary. Also make sure MaxSpareServers is not set too high.

Then save the file and quit.

Finally we copy WeBWorK's icon file favicon.ico to Apache's html directory. 

$ sudo cp /opt/webwork/webwork2/htdocs/favicon.ico /var/www/html
[sudo] password for wwadmin: <wwadmin password>

Now stop and start Apache. We do it this way to make sure the MPM gets changed. 

$ sudo systemctl stop apache2
[sudo] password for wwadmin: <wwadmin password>
$ sudo systemctl start apache2

Test your configuration

Test the /webwork2 location by visiting http://yourserver.yourschool.edu/webwork2. You should see the WeBWorK home page with no courses listed. Actually the directory /opt/webwork/courses/ does contain the modelCourse but the modelCourse is not a real course so you will get an error message if you try to log into it. It will be used a as model for setting up other courses. For this reason /opt/webwork/courses/modelCourse/ contains a file named hide_directory and so the modelCourse is not visible.

If Something is Wrong

If something is wrong one of the first things to check is that the config files have been edited correctly (e.g. one time a wrapped line in localOverrides.conf caused me problems, another time it was a missing single quote). A quick way to check this is to do a diff between the edited and distributed versions and check that diff reports the changes you made and only those. Another thing is to look at the Apache error log which is located at /var/log/apache2/error.log. 

$ cd /etc/apache2/
$ diff apache2.conf apache2.conf.bak1
$ cd /opt/webwork/webwork2/conf/
$ diff site.conf site.conf.dist
$ diff localOverrides.conf localOverrides.conf.dist
$ diff webwork.apache2.4-config webwork.apache2.4-config.dist
$ tail /var/log/apache2/error.log

If something is wrong and you fix it, you will have to restart Apache for the changes to take effect 

$ sudo systemctl restart apache2
[sudo] password for wwadmin: <wwadmin password>

Create the admin Course

Course Administration gives information about creating courses. Here we will give explicit instructions for doing this. (You may need to become root or use sudo to execute some of these commands.) 

$ cd /opt/webwork/courses
$ /opt/webwork/webwork2/bin/addcourse admin --db-layout=sql_single --users=adminClasslist.lst --professors=admin
$ sudo chown -R www-data:www-data  admin 
[sudo] password for wwadmin: <wwadmin password>

where the last line makes the course admin and its subdirectories owned by the Apache server and readable/writeable by the wwadmin user.

Now go to http://yourserver.yourschool.edu/webwork2 and should see the WeBWorK home page with Course Administration listed at the top. Click on it and login with Username admin and Password admin . This first thing you should do is register your new WeBWorK installation. It's quick and easy, just click on Register. IMPORTANT The next thing you should do is click on User Settings and change admin 's password to something more secure than admin .

Unless you choose otherwise, users with admin privileges in the admin course (i.e. WeBWorK administrators) will automatically be added to new courses with admin privileges and the same password as in the admin course. Initially the only such user is admin (hopefully you are not confused by the fact that the course admin has a user named admin). It's usually convenient make yourself a WeBWorK administrator. To do this (assuming you are logged in as admin to the admin course at http://yourserver.yourschool.edu/webwork2/admin )

  1. Click on Classlist Editor in the left panel
  2. Click the Add tag and click Take Action!
  3. Enter the appropriate information (you can use your Login Name as the Student ID if you want and also you can leave the last three items blank) and click Add Students
  4. Click on Classlist Editor in the left panel again
  5. When you enter a new student, by default their Student ID is used as their password. We'll change this now.
  6. Select yourself with a check mark and click the Password tag and click Take Action!. (Note as a safely mechanism you can not change the password for the user you are logged in as, currently admin, this way)
  7. Enter the password and then click Take Action!
  8. Finally give yourself admin privileges by selecting yourself with a check mark, clicking the Edit tag and then clicking Take Action! (or by just clicking on the "pencil" next to your login name which is a much faster way to edit classlist data for a single user)
  9. Now at the far right change Permission Level from student to admin
  10. Then click Take Action!

At some point you will probably want to hide the admin course so that it is not listed on the WeBWorK home page. As we noted above the modelCourse, which is already hidden, is not a real course so you will get an error message if you try to log into it. This is a good reason to hide it. The modelCourse is very useful as a model (hence its name) for setting up other courses. The admin course is used for administering WeBWorK and even though regular users can not log into it (you did change the admin password, didn't you!!), it a little bit cleaner and safer to hide it from prying eyes. To hide (or unhide) a course select Hide Inactive courses in the admin course and follow the directions. When hidden a course will not show up in the courses list on the WeBWorK home page. It will still appear in the Course Administration listing. If you do this you will still be able to access the admin course using the URL http://yourserver.yourschool.edu/webwork2/admin but you will not see a link for it on the WeBWorK home page http://yourserver.yourschool.edu/webwork2 .


Now go to http://yourserver.yourschool.edu/webwork2 and no course will be listed.

Checking for and Installing Hotfixes

The following commands show you how to check for and install bug fixes. Important Note: These commands check and retrieve the main branch which gives the latest stable release of the software package (webwork2, pg, etc.) with bug fixes. If a stable release newer than 2.16 exists for webwork2 and/or pg, that will be checked and retrieved which is probably not what you want. Please check before updating. The best way to do that is to look at https://github.com/openwebwork/webwork2/blob/main/VERSION and https://github.com/openwebwork/pg/blob/main/VERSION.

To check if there are bug fixes, do the following.

Updating the webwork2 code

First we check for updates to the webwork2 code: 

cd /opt/webwork/webwork2/
git remote show origin

This will print several lines of data, but the last line will tell you if your copy is up to date or out of date. If it is out of date, run 

git pull origin

and restart apache2.

Updating the pg code

Now check for updates to the pg code: 

cd /opt/webwork/pg/
git remote show origin

This will print several lines of data, but the last line will tell you if your copy is up to date or out of date. If it is out of date, run 

git pull origin

and restart apache2.

Restart apache2

Important: After updating either webwork2 or pg, you have to restart apache2 

$ sudo systemctl restart apache2
password:<wwadmin password>

Updating the OPL

The following assumes you have already installed the OPL. For that see #Install the Open Problem Library below. Now check for updates to the Open Problem Library (OPL): 

$ cd /opt/webwork/libraries/webwork-open-problem-library
$ git remote show origin

This will print several lines of data, but the last line will tell you if your copy is up to date or out of date. If it is out of date and you want to update, run: 

$ git pull origin
$ OPL-update

Important Note: The OPL contains over 37,000 problems and if one new problem is added, the above will report the OPL is out of date. I would suggest you update the OPL maybe once or twice a semester. Also the version of the OPL contained in the WW 2.17 Virtual Machine Image and in the WW 2.17 Amazon Machine Image is current as of August 1, 2022.

Updating the OPL is pretty much risk free since changes usually involve only a relatively small number of individual problems and the vast majority of problems remain unchanged. Updating the OPL does not require restarting apache2.

Starting and Stopping Apache and MySQL

If you make changes to the system, you may need to restart apache2 in order for the changes take effect. On rare occasions you may need to restart MariaDB. These system services are controlled with systemctl. Most systemctl commands must be run as root via sudo.

Run 

$ systemctl --help

to obtain a list of all possible commands. The primary commands being start, stop, restart and status.

Starting and Stopping Apache

To restart the apache2 web server run the command 

$ sudo systemctl restart apache2

You can also stop apache2 with 

$ sudo systemctl stop apache2

and start it with 

$ sudo systemctl start apache2

To obtain more information about the apache2 server run 

$ systemctl status apache2

Starting and Stopping MySQL or MariaDB

To start the MariaDB or MySQL server run the command 

$ sudo systemctl start mysql

To stop the MariaDB or MySQL server run the command 

$ sudo systemctl stop mysql

To restart the MariaDB or MySQL server run the command 

$ sudo systemctl restart mysql

To obtain more information about the MariaDB or MySQL server run 

$ systemctl status mysql

Install the WeBWorK Problem Libraries

Before we create a real course we will install the WeBWorK Problem Libraries.

Install the Open Problem Library

The Open Problem Library consists of both WeBWorK problems and methods for searching and selecting problems. Also it contains as sub libraries many of the other standard libraries. We have to load a database for searching it.

Run the OPL-update script which will download the OPL metadata release and checkout the corresponding tag in the library as needed for the Library Browser in WeBWorK. Since this is a new installation, we do not have any OPL statistics to upload (see OPL_Problem_Statistics), so we run the two commands: 

$ export SKIP_UPLOAD_OPL_STATISTICS=1
$ OPL-update

If at some time in the future you want to upgrade the Problem Library, the process is easy, see Updating the OPL. Note that this is something you should do fairly often so that your library is up to date with new problems and bug fixes for old ones.

Set up the access to the Contrib directory

The Contrib directory contains contributions to the OPL that may not have been formally accepted into the main collection of OPL problems. This may be because the contribution is recent and has not yet been reviewed or because the problems are not properly tagged as is the case with the CAPA problem collection. It also contains the original versions of problems that have been accepted into the OPL (the idea being that the original authors maintain control of problems in the Contrib directory but problems in the OPL are controled by the editors). This step creates a button in the Library Browser which gives a direct link to the Contrib directory.


Put a link to the Contrib directory in the 

/opt/webwork/courses/modelCourse/templates/

directory so that when we create courses copying templates from the modelCourse, the Contrib directory will be available. Actually this link, called Contrib, has already been added so no action on your part is required.

If you just want to do this for individual courses, not all courses then remove the link in the modelCourse above, and then do the following. Note we don't have any individual courses yet. But for example after creating myTestCourse below, to set up access to the Contrib directory from myTestCourse, do the following 

$ cd /opt/webwork/courses/myTestCourse/templates/
$ sudo $ ln -s /opt/webwork/libraries/webwork-open-problem-library/Contrib Contrib
[sudo] password for wwadmin: <wwadmin password>

Set up the Rochester and Union Libraries

This step is optional. It creates buttons in the Library Browser which give direct links to the Rochester and Union libraries. If you don't do this, you can find these libraries and others under the OPL Directory button. But you can follow this example if you want to create button(s) for direct access to other sub libraries.

First we need to edit localOverrides.conf one last time 

$ cd /opt/webwork/webwork2/conf
$ nano localOverrides.conf

Search for courseFiles{problibs} and scroll down several lines to the lines 

#       rochesterLibrary => "Rochester",
# 	unionLibrary     => "Union",

Uncomment these lines (i.e. remove the #) so they become 

      rochesterLibrary => "Rochester",
      unionLibrary     => "Union",

Then save the file and quit.

We next put links to the Rochester and Union Libraries in the modelCourse so that when we create courses copying templates from the modelCourse, these libraries will be available. Skip this step if you usually only want to use Open Problem Library. Note that the Rochester, Union and other libraries are contained in the OPen Problem Library and are accessible from there under the OPL Directory button in the Library Browser. This step simply creates buttons in the Library Browser so that you can access the Rochester and Union libraries directly. 

$ cd /opt/webwork/courses/modelCourse/templates/
$ ln -s /opt/webwork/libraries/webwork-open-problem-library/OpenProblemLibrary/Union unionLibrary
$ ln -s /opt/webwork/libraries/webwork-open-problem-library/OpenProblemLibrary/Rochester rochesterLibrary

If you want to put another library into the modelCourse, just do the analogous thing. If you just want the additional library in a particular course, add the link in the templates directory of that course. If you look in the directory /opt/webwork/libraries/webwork-open-problem-library/OpenProblemLibrary/ you might find other libraries that are not yet listed in global.conf and these can be added in the same way as the Rochester and Union libraries. Finally if you add a library with non standard symbols in the name (e.g. uva-statLibrary) you have to use single quotes when adding it to global.conf, e.g.
         'uva-statLibrary' => "UVA-Stat",
It's easier to just avoid such names.

Install and Set Up the CAPA Library

This step is optional. It installs and sets up the CAPA Library, which is a library of physics problems.

We have to put a link in the templates directory of every course that needs access to the CAPA Library. If you want to have every course you create have access to the CAPA Library put the link in the modelCourse. Actually this link, called capaLibrary, has already been added to 

/opt/webwork/courses/modelCourse/templates/

so no action on your part is required.

If you just want to do this for individual courses, not all courses then remove the link capaLibrary in the modelCourse above, and then do the following. We don't have any yet. But for example after creating myTestCourse below, to set up access to the CAPA Library from myTestCourse, do the following 

$ cd /opt/webwork/courses/myTestCourse/templates/
$ sudo ln -s /opt/webwork/libraries/webwork-open-problem-library/Contrib/CAPA/   capaLibrary
[sudo] password for wwadmin: <wwadmin password>


and do the analogous thing for every course that needs access to the CAPA Library. Then to gain access to the CAPA Library from the course, simply go to the Library Browser and click on the CAPA button.

Create Your First Actual Course

Since we have edited site.conf and localOverrides.conf and these are critical files, it would be a good idea to run 

$ cd /opt/webwork/webwork2/conf
$ diff site.conf site.conf.dist
$ diff localOverrides.conf localOverrides.conf.dist

and check that you haven't made any mistakes (e.g. by introducing an inadvertent line break, etc.). If there are any mistakes, correct them. Remember that any time you change either of these files you must restart the Apache webserver in order for these changes to take effect.

Since we have edited global.conf and haven't restarted Apache we do so now. 

$ sudo apache2ctl graceful
password:<wwadmin password>

Now log into the admin course ( http://yourserver.yourschool.edu/webwork2/admin or, if you have not hidden the admin course, click on Course Administration on WeBWorK's home page http://yourserver.yourschool.edu/webwork2/ ) as yourself or admin and

  1. click on Add Course
  2. For Course ID enter myTestCourse
  3. For Course Title enter My Test Course
  4. Enter your institution
  5. Leave Add WeBWorK administrators to new course and Copy simple configuration file to new course checked
  6. Add an additional instructor if you wish
  7. Copy templates from: modelCourse (the default action)
  8. Click on Add Course
  9. Click Log into myTestCourse

and log in either as admin or yourself (if you added yourself as an additional instructor above).

At some point you will probably want to "hide" myTestCourse from general view but you already know how to do that.

Test that Things are Working Properly

We will test out a few important parts of WeBWorK. If you run into problems, you should look at the Apache error log which is located at /var/log/apache2/error.log.

Click on Hmwk Sets Editor on the Main Menu. Then select Import, select setDemo.def from the Import from where drop down list and select all current users from the assigning this set to drop down list. Then hit Take Action!

Now click on Homework Sets on the Main Menu and click on Demo. Then look at the problems. Mathematical equations should be displayed nicely by MathJax (right click on the equation for info). You can also display equations as images but this is not recommended. If you do and have problems, edit the file Constants.pm in the directory /opt/webwork/webwork2/lib/WeBWorK. Change the line $WeBWorK::PG::ImageGenerator::PreserveTempFiles = 0; to ...::PreserveTempFiles = 1;. Then restart Apache and view the first couple problems or some new ones. Then look in the directory /opt/webwork/webwork2/tmp/. cd to one of the ImageGenerator.../tmp/ directories and look at the error and log files there. When you fix the problem remember to edit ...::PreserveTempFiles = 1; back to 0 and restart Apache or you will be saving a lot of unnecessary files. Another useful trick is to try downloading a hard copy of an assignment and then (assuming there are errors) looking at the various log files that are linked to on the output page.

Note that since you probably used "admin" to login you have Permission Level "admin" so things look more complicated than if you were just a regular professor with Permission Level "professor". In particular any time you view a problem, you have the option to "Edit tags" which you probably do not want to do. If these bothers you, login as a professor (see below).

Continue looking at problems to see if everything is working properly.

Next click on Problem List to bring back the Problem List Page and click on Download PDF .... The page is a little complicated because you are an admin so you see the professor view (students see a very simple page) but you can just scroll to the bottom and click on Generate hardcopy for selected users and selected sets. If you get an error (you shouldn't) just click Download Hardcopy to get what was generated. Also you can see links to various informational files that are available if you run into problems (normally these files are removed if there are no errors). If you want to preserve these tmp files, set $WeBWorK::ContentGenerator::Hardcopy::PreserveTempFiles to 1 in the file Constants.pm in the directory /opt/webwork/webwork2/lib/WeBWorK and then restart Apache. Remember to set this back to 0 after debugging. You can find these tmp files under /opt/webwork/webwork2/tmp/, then look under your course, hardcopy, and user. You will have to switch to being the root user to access the final subdirectory containing the tmp files.

Another thing to do is to use Email on the Main Menu. Again this page is a little complicated because you can do a lot of things with it (including mail merge) but at this point just select yourself in the list to the right and hit Send Email at the bottom. You should receive two emails. One is the message you just sent and the other is an email with subject "WeBWorK email sent" giving information on your mailing.

As a final test click on Library Browser on the Main Menu. Click Open Problem Library (actually it should already be selected so it will be greyed out) and select a Subject, Chapter and Section and then hit View Problems. The first 20 of your selected problems will be displayed. You can also test that you can access any additional Problem Libraries that you installed. Note that if you just happen to view some statistics problems that require the R server, you will get errors (since we have not installed R --- at least not yet).

Note: if when using the Library Browser you find that after selecting a Subject, you can not select a Chapter (and usually you will see an error from setmaker.js: /webwork2/instructorXMLHandler: e.g. Timeout or Forbidden), the most common reason is that $server_root_url has not been set "correctly" in the /opt/webwork/webwork2/conf/site.conf file. A common error is to use forget http:// or to use http:// when you should use https:// or to just have the wrong domain name or ip address. But sometimes "localhost" will work when the correct ip address or url will not, for example in situations when you are using a virtual machine as your host.

If all the above tests work, you can be pretty confident that WeBWorK is working properly.

Go back to Hmwk Sets Editor on the Main Menu. Then select Import, select setOrientation.def from the from drop down list and select all current users from the assigning this set to drop down list. Then hit Take Action!. Then go through the Orientation problems. This is a good first set to use for introducing students to WeBWorK. Also you can Import set0.def and setMAAtutorial.def and look through those problems.

If you are new to WeBWorK or even if you are a pro, you should probably add a regular student to myTestCourse and log in as that student to see what the student interface looks like. It's much simpler than the professor or admin interfaces. Also for the same reason you should probably add professor to myTestCourse and log in as that professor to see what the professor interface looks like.

Click on Classlist Editor on the Main Menu. Then select Add, for "Add how many students?" pick 2 and hit Take Action!. Then add two students, say

  • Last Name "Smith", First Name "Jane" , Student ID "jsmith" and Login Name "jsmith"
  • Last Name "A", First Name "Prof" , Student ID "profa" and Login Name "profa"

and make sure to select all sets to assign them to both of them. Then hit Add Students.

Now we make "profa" a professor. Again click on Classlist Editor on the Main Menu. The fast way is to click on the "pencil" by "profa", set the "Permission Level" to "professor" and hit Take Action!.

Jane Smith's initial password will be her Student ID jsmith. Now login as Jane Smith and play around a little.

Prof A's initial password will be her Student ID profa. You should also login as Prof A and play around a little.

You can also add "practice users" and login as one of those to see how you can grant partial access to your course for practice or other reasons (e.g. auditors who don't want to be graded). To do this Click on Classlist Editor, select Import, select the "demoCourse.lst" (the only classlist available at this point) and hit Take Action!.

More House Keeping

Hide the admin and myTestCourse courses

Log out of myTestCourse if you are logged in and go to the WeBWorK Welcome page. Click on Course Administration and login as admin with the new admin password you set for the admin course. Select "Hide Inactive Courses" and select the courses you want to hide and hit "Hide Courses". If you go back to the WeBWorK Welcome page, you will see no courses listed. You can still access these courses directly by 

http://192.168.76.128/webwork2/admin 
http://192.168.76.128/webwork2/mytestcourse

where of course you should use your actual ip address or url.

Replace the default landing page

You probably should replace /var/www/html/index.html with a page which redirects to the webwork course list at your site. Something like the following should work: 

 <html>
 <head>
   <META http-equiv="Pragma" content="no-cache">
   <META HTTP-EQUIV="Refresh" CONTENT="0;URL=https://mysite.mydomain.edu/webwork2/">
   <title>WeBWorK site - redirects to main page</title>
 </head>
 <body style="text-align: center;">
   You probably want to use the
   <a href="https://mysite.mydomain.edu/webwork2/">the WeBWorK list of courses page</a>
 </body>
 </html>

The institution logo (which is the MAA logo by default) appears on every WeBWorK page. You can replace with you own logo by doing the following. We took these directions verbatim from Alex Jordan's Forum post https://webwork.maa.org/moodle/mod/forum/discuss.php?d=5642.

All you need to do is add lines like these to a config file like localOverrides.conf:

$institutionLogo = 'myimage'; $institutionURL = 'URL for target if a user clicks on the image'; $institutionName = 'Name of the target, to be used in alt text';

myimage is an image file that you place in webwork2/htdocs/themes/math4/images/. It could be for example 'myimage.svg' containing some text.

The easiest way to do this is to search for the lines 

# The institution logo should be an image file in the theme's images folder
#$institutionLogo = 'my_school_logo.png';
#$institutionURL  = 'http://www.myschool.edu';
#$institutionName = 'My University';

in /opt/webwork/webwork2/conf/localOverrides.conf, remove the #'s from the last three lines and enter your information. If you want to just make the change for an individual course, copy the code and put it in /opt/webwork/courses/Course_Name/course.conf.

Optional Configurations

You should definitely consider implementing the following optional configurations.

Option A configures Apache so that access to WeBWorK will be through an encrypted connection (SSL) with an https: URL.

Option B installs and configures the R server for statistical computing. Many statistics and probability problems (mostly contributed by faculty at the University of British Columbia) require this.

Option C sets up log rotation for WeBWorK's timing log.

Implement Option A (SSL)

Option A configures apache so that access to WeBWorK will be through an encrypted connection (SSL) with an https: URL. Note that TLS is the successor protocol to SSL and is used everywhere. So that when we and others use the more common acronym SSL, we really are talking about TLS.

First we have to obtain an official SSL certificate or generate a self-signed one which can be used for testing purposes. If students will be using your server, it is better to obtain an official SSL certificate since using a self-signed certificate with cause warning messages to be displayed when students connect to the server.

Obtain an Official SSL Certificate

Talk to the networking group on your campus about obtaining an official certificate. You can find information on the net about certificate providers, e.g. http://www.sslshopper.com/certificate-authority-reviews.html . Certbot (https://certbot.eff.org/) which uses Let's Encrypt certificates (https://letsencrypt.org/) is a good option if you are not using your organization's official certificates.

The certificate goes in /etc/ssl/certs/ and the key file goes in /etc/ssl/private/.

Use a self-signed Certificate

When we installed the package openssh-server a self-signed certificate was automatically created. The certificate is stored at 

/etc/ssl/certs/ssl-cert-snakeoil.pem

and the private key at 

/etc/ssl/private/ssl-cert-snakeoil.key

This certificate and key may be regenerated manually with the following command (needs root privileges ie sudo): 

$ sudo make-ssl-cert generate-default-snakeoil --force-overwrite
[sudo] password for wwadmin: <wwadmin password>

which you might want to do since I believe the original certificate is only valid for 365 days.

In the instructions below we will use the provided self-signed certificate (ssl-cert-snakeoil.pem and ssl-cert-snakeoil.key) but you can also generate your own using openssh following instructions on the web. As we said above, for a production server, you should really use an official certificate.

Set up Apache to use SSL

First we enable the mod_ssl module 

$ sudo a2enmod ssl
[sudo] password for wwadmin: <wwadmin password>

Now we have to configure Apache to use SSL. 

$ cd /etc/apache2/sites-available/
$ sudo cp default-ssl.conf default-ssl.conf.bak1
[sudo] password for wwadmin: <wwadmin password>
$ sudo nano default-ssl.conf

Our self-signed certificate and key files are named ssl-cert-snakeoil.pem and ssl-cert-snakeoil.key. If you are using official files, put their names in the lines below. You will also have to edit the Certificate Chain, Certificate Authority and possibly other items. Instructions for doing so are beyond the scope of this document. You might look at https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-22-04

Search for the lines 

SSLCertificateFile      /etc/ssl/certs/ssl-cert-snakeoil.pem
SSLCertificateKeyFile /etc/ssl/private/ssl-cert-snakeoil.key

and replace ssl-cert-snakeoil.pem and ssl-cert-snakeoil.key by the names of your certificate. Since in these instructions we are using ssl-cert-snakeoil.pem and ssl-cert-snakeoil.key, we can just leave the lines as is.

Then save the file and quit. And enable default-ssl.conf 

$ sudo a2ensite default-ssl.conf
[sudo] password for wwadmin: <wwadmin password>

Finally we restart Apache 

$ sudo systemctl restart apache2

and test things. Connect to https://yourserver.yourschool.edu/webwork2/myTestCourse . If you are using the snakeoil certificates you will see warning messages (e.g. NET::ERR_CERT_AUTHORITY_INVALID) and you will be asked to accept the risk. After you do so things should work just as before except that the connection will be via https.

Redirect http requests to https

Assuming that everything is working, the next thing we do is set things up so that requests to http://yourserver.yourschool.edu/webwork2/ are automatically redirected to https://yourserver.yourschool.edu/webwork2/. 

$ cd /etc/apache2/sites-available
$ sudo cp 000-default.conf 000-default.conf.bak1
[sudo] password for wwadmin: <wwadmin password>
$ sudo nano 000-default.conf

In the 

<VirtualHost *:80>

section just under the line 

DocumentRoot /var/www/html

add the line 

Redirect permanent /webwork2 https://yourserver.yourschool.edu/webwork2

where of course you should edit yourserver.yourschool.edu appropriately. Then save the file and quit. Restart Apache 

$ sudo service apache2 restart

and try connecting to http://yourserver.yourschool.edu/webwork2/. The real connection should be through https://yourserver.yourschool.edu/webwork2/.

Check site.conf

This is important. We have to check the value of $server_root_url in webwork2/conf/site.conf to make sure it uses https (so it should read e.g. https://yourserver.yourschool.edu). If you don't do this, your may run into strange problems in the Library Browser. To check, open the Library Browser, select a subject and then click on the chapter area. If you see a drop down list of chapters, things are working properly.

Now we check and edit if necessary site.conf 

cd /opt/webwork/webwork2/conf
nano site.conf

In the line 

$server_root_url = ...

replace http by https if necessary. Then save the file, quit and restart apache 

sudo service apache2 restart  
[sudo] password for wwadmin: <wwadmin password>

Implement Option B (Rserve)

Here we will install and configure the R server for statistical computing. Many statistics and probability problems (mostly contributed by faculty at the University of British Columbia) require this.

See the documentation (from which we have borrowed heavily) R_in_WeBWorK for more detailed information.

Install the R server

$ sudo apt install r-cran-rserve
[sudo] password for wwadmin: <wwadmin password>

and check that R is running 

$ R

You should see something very similar to 

R version 4.1.2 (2021-11-01) -- "Bird Hippie"
Copyright (C) 2021 The R Foundation for Statistical Computing
...
Type 'q()' to quit R.

>

and then quit 

> q()
Save workspace image? [y/n/c]: n

Configure Webwork with the location of the R server

We have to edit the localOverrides.conf file. 

$ cd /opt/webwork/webwork2/conf
$ nano localOverrides.conf

Search for the line 

#$pg{specialPGEnvironmentVars}{entryAssist} = 'WIRIS';

and under that line add the following 

################################################################################
#location of the R server
################################################################################
$pg{specialPGEnvironmentVars}{Rserve} = {host => 'localhost'};

Then save the file and Quit.

Set up Rserve to run as a daemon at system boot

This is somewhat complicated. I'm basically following instructions from https://github.com/geordielad/rserve-systemd-unit

First we create a user with limited privileges to run rserve. 

$ sudo adduser rserveuser --system --shell=/bin/false --no-create-home --disabled-password --disabled-login


Next we create a file to automatically start Rserve 

$ cd
$ nano rserve.service

Now copy and paste the following code into nano 

[Unit]
Description=Rserve

[Service]
Type=forking
PIDFile=/var/run/rserve/rserve.pid

# Define runtime directory
RuntimeDirectory=rserve
RuntimeDirectoryMode=750

User=rserveuser
Group=nogroup

ExecStart=/usr/bin/R CMD Rserve --quiet --vanilla --RS-pidfile /var/run/rserve/rserve.pid

[Install]
WantedBy=multi-user.target

and then save the file and quit. Change the owner to root, move the file to the proper location and register it. 

$ sudo chown root:root rserve.service
[sudo] password for wwadmin: <wwadmin password>
$ sudo mv rserve.service /etc/systemd/system
$ sudo systemctl daemon-reload

Next we enable the service to start when the system starts 

$ sudo systemctl enable rserve.service

and finally set up some needed links 

$ cd /usr/lib/R/bin/
$ sudo ln -s ../site-library/Rserve/libs/Rserve
$ sudo ln -s ../site-library/Rserve/libs/Rserve.dbg

Test that things are working properly

First start Rserve manually 

$ sudo systemctl start rserve
 [sudo] password for wwadmin: <wwadmin password>

and run 

$  sudo lsof -i -P -n | grep LISTEN

and you should see that Rserve is listening on port 6311

Next test that WeBWorK problems using R run properly. In WeBWorK, click on Library Browser on the Main Menu. Then click Open Problem Library (actually it should already be selected so it will be greyed out). Now select "Statistics" as Subject, "Bayesian inference" as Chapter and "Posterior distribution" as Section and then hit View Problems. Also test a problem with graphics, e.g. select "Statistics" as Subject, "Hypotheses tests" as Chapter and "One-way ANOVA" as Section and then hit View Problems.

If the problems display with no error messages, all should be well (for the graphics problem, look at Library/UBC/STAT/STAT300/hw06/stat300_hw06_q01.pg). To be totally sure, click on the "eye" (Try it) in the upper right corner and test the problem. If there are no error messages, congratulate yourself. Everything works.

Finally reboot your server (to test that the Rserve starts automatically on boot up) and run 

$ sudo systemctl status rserve.service
[sudo] password for wwadmin: <wwadmin password>

to check that all is well and just to be redundant 

$  sudo lsof -i -P -n | grep LISTEN

again. Now we are sure that Rserve automatically starts when the system is booted.

Loading additional modules

This step should not be necessary unless you are writing or using WeBWorK problems that need additional resources beyond what is loaded by default. An example is using R to compute complex eigenvalues which requires the Math::Complex module (see https://webwork.maa.org/moodle/mod/forum/discuss.php?d=5577). The error message in such a case would be similar to 

Can't locate object method "make" via package "Math::Complex" (perhaps you forgot to load "Math::Complex"?) at /usr/share/perl/5.30/Math/Complex.pm line 329
   Died within Math::Complex::cplx called at line 351 of /usr/local/share/perl/5.30.0/Statistics/R/IO/QapEncoding.pm
   from within Statistics::R::IO::QapEncoding::decode called at line 236 of /usr/local/share/perl/5.30.0/Statistics/R/IO/Rserve.pm
   from within Statistics::R::IO::Rserve::eval called at line 26 of [PG]/lib/Rserve.pm
   from within Rserve::try_eval called at line 146 of [PG]/macros/RserveClient.pl
   from within main::rserve_eval called at line 40 of (eval 4456)

First note that the required module must be installed on your server. The Math::Complex module already is which we can see by running the command 

perl -MMath::Complex -e 'print "installed!\n"'

which returns installed!. If it were not installed you would see at lot of gibberish. In general to test if a Perl module is installed and working on your system, issue the above command, replacing Math::Complex with the name of the module. To install additional Perl modlues , see Installation of Other Perl Modules with cpanm above.

We need to load Math::Complex into WeBWorK's safe compartment. For this we have to edit the localOverrides.conf file. 

$ cd /opt/webwork/webwork2/conf
$ nano localOverrides.conf

Now search for the line 

# Additional PG modules

and under the line 

#push (@{${pg}{modules}}, [qw(TikZ_Image2)]);

add the lines 

push @{$pg{modules}},
[qw( Math::Complex )],
;

You can add as many modules as you need this way.

Then save the file and Quit.

Implement Option C (Logrotate)

Here we will set up log rotation for WeBWorK's timing log which can grow huge especially if you have a large number of users. The timing.log gives timing information on every action in WeBWorK (see WeBWorK_performance) and can be used to assess the performance of your server.

Create a WeBWorK configuration file for Logrotate

Logrotate’s configuration files are located in /etc/logrotate.d. Now we create one for WeBWorK. 

$ sudo nano /etc/logrotate.d/webwork

Now copy and paste the following code into nano 

/opt/webwork/webwork2/logs/timing.log {
su www-data www-data
weekly
missingok
rotate 15
compress
delaycompress
notifempty
}

and then save the file and quit. The backup will be done weekly and we are keeping 15 weeks (approximately one semester) worth of logs. The most recent backup will not be compressed but all older ones will be. We are not explicitly creating a new timing.log file because WeBWorK will automatically create one if it's missing. If you want to check that it works you can run logrotate with the configuration file (make sure you have done something with WeBWorK so that the timing.log is not empty): 

sudo logrotate -f /etc/logrotate.d/webwork
[sudo] password for wwadmin: <wwadmin password>

Then if you look in /opt/webwork/webwork2/logs, you should see 

timing.log.1

You will not see a timing.log file unless someone has been doing something with WeBWorK. If there is no timing.log file do something yourself (e.g. login to a course) and then you should see 

timing.log
timing.log.1

Now run logrotate again 

sudo logrotate -f /etc/logrotate.d/webwork
[sudo] password for wwadmin: <wwadmin password>

and do something in WeBWorK and you should see 

timing.log
timing.log.1
timing.log.2.gz

Here is what is going on. timing.log.1 was renamed to timing.log.2 and compressed giving timing.log.2.gz. timing.log was renamed to timing.log.1. And the something you (or someone else) did in WeBWorK created a new timing.log file. A similar procedure will happen weekly until there are a total of 15 backups after which the oldest one will be deleted.

Known Issues

Here are the known issues with this release.

PGbasicmacros.pl

Displaying certain symbols (e.g. {, },<,>,≤, ≥) in the text (not in Math Mode) of a WeBWorK problem fails. An example is Problem 1 in Set 0 in "myTestCourse" (see Test that Things are Working Properly below). For information on this see https://github.com/openwebwork/pg/issues/473. This can be fixed. However the fix causes trouble with WeBWorK problems that use the associated macros incorrectly in Math Mode (see https://webwork.maa.org/moodle/mod/forum/discuss.php?d=5727) and there are quite a few more problems that use them incorrectly than correctly. If you use any of these problems, the easiest solution would be to not perform the fix.

If you do what to proceed with the fix we need to edit the PGbasicmacros.pl file. 

$ cd /opt/webwork/pg/macros
$ cp PGbasicmacros.pl PGbasicmacros.pl.bak1

$ nano PGbasicmacros.pl

Look for the line 

HTML_MathJax     => [ "HTML_dpng", "HTML_tth", "HTML", ],

and replace it by 

#HTML_MathJax     => [ "HTML_dpng", "HTML_tth", "HTML", ],
HTML_MathJax     => [ "HTML_dpng", "HTML", "HTML_tth", ],

Then save the file and Quit.

Housekeeping

Remove temporary files

WebWorK no longer generates a lot of temporary files but it is still a good idea to clean them out once in awhile. Temporary files are stored under the directories /opt/webwork/webwork2/tmp and /opt/webwork/webwork2/htdocs/tmp. It is safe to delete everything in these tmp directories. If you want, you can follow the directions below to set up Cron jobs to do this automatically.

Using Cron Jobs to remove temporary files

It is a good idea to clean out temporary files on a regular automatic schedule. The following two cron jobs will accomplish this. They are run every six months (in January and July), on the first and second days of the month at 0330 hours. These cron jobs should be run as root. We use crontab to edit the crontab file: 

$ sudo -s
[sudo] password for wwadmin: <wwadmin password>
# crontab -e

Now add the following lines at the end of the file 

30 03 1 1,7 *  find /opt/webwork/webwork2/tmp/*  -name "*" ! -name "README" -delete
30 03 2 1,7 *  find /opt/webwork/webwork2/htdocs/tmp/* -name "*" ! -name "README" -delete

and save the file and quit. Then exit acting as root 

# exit
$

Where to go From Here

You should play around with myTestCourse e.g. click on Library Browser and browse the Problem Library.

Look at A day in the life of a WeBWorK instructor.

Read Course Administration for more information about creating courses.

Under Categories below click on Administrators to see a listing of other WeBWorK documentation for system administrators.

-- Main.ArnoldPizer and Peter Staab - August 4, 2022

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