RedHat Linux installation

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Note: This document is about installing Moodle 3.7 in an RedHat Enterprise Linux (RHEL) 8


Server Installation

  • Web Server
    • Moodle 3.7 needs PHP 7.1 and RHEL8 comes with PHP 7.2.[1]
  • Database
    • Moodle 3.7 needs MariaDB 5.5 or MySQL 5.6, and RHEL8 comes with MariaDB 10.3 and MySQL 8.0 (They cannot be installed at the same time).[2]
  • BEWARE OF the 'Server with a GUI' option, it may not work as expected.

Note: Set up the firewall if necessary. You probably only need to enable HTTP/HTTPS (and perhaps FTP and SSH) access to your server machine, unless you know the difference.

Network Interface

During installation, under "System" -> "Network & Host Management", remember to enable the NIC. It's not enabled by default.

Configure hostname and domain name

Type system-config-network to open the GUI editor. Click on the DNS tab. In the "DNS Search Path" fill in your domain name for example myuniversity.edu. Now ensure the "Hostname" contains the computer name you will use and click activate to make changes

System Registration

  • To receive package updates, create a user account at redhat.com, and then login and register as developer at https://developers.redhat.com/
  • Subscribe the system by:
subscription-manager register --auto-attach

Enter the username and password as requested.

  • Update the system and then reboot
yum update
reboot

See [3]

SELinux

Default RedHat Enterprise Linux comes with SELinux set to 'enforcing'. But this may cause user problem accessing web content placed at directory other than the default directory (/var/www/html) or other access problem. If you are not used to SELinux and setting permissions, it's (maybe less secure but) often easier to lower the SELinux level to 'permissive' or even 'disabled'.

# vi /etc/sysconfig/selinux

SELINUX=disabled

See the CentOS [4]

Firewall

The internal firewall (RHEL since version 7 uses 'firewalld' instead of 'iptables' by default) is on by default. It will block the access to the web server. You may stop it first to test connection:

service firewalld stop

and then either disable it:

chkconfig firewalld off

or enable permanent HTTP access to it, you may want to enable HTTPS as well:

firewall-cmd --permanent --zone=public --add-service=http
firewall-cmd --permanent --zone=public --add-service=https

Restart the firewall and then check the allow status:

service firewalld restart
firewall-cmd --zone=public --list-services

To use iptables instead of firewalld, see [5]

MariaDB / MySQL

  • Make sure at least 'mariadb' and 'mariadb-server' packages are installed.
    • (use "mysql" and "mysql-server" for MySQL)
yum install mariadb mariadb-server
  • Then get the daemon running, it is not running by default. And set it to auto-start. See also [6]
    • (use "mysqld" for MySQL)
service mariadb start; chkconfig mariadb on
  • Edit /etc/my.cnf (May be different for MySQL)
vi /etc/my.cnf

Scroll down to the [mysqld] section and under "Basic Settings", add the following line under the last statement.

innodb_file_format = Barracuda

innodb_file_per_table = 1

innodb_large_prefix
  • If you haven't yet, as root, change the MariaDB/MySQL root password
    • mysqladmin -u root password mysqlpass (<-- should change this to something of your own)
    • Or run 'mysql_secure_installation' to set password for root and secure the installation
  • Next, set up the MariaDB/MySQL database (see http://moodle.org/doc/?file=install.html#Database for more details)
  • Launch MariaDB/MySQL as root
    • mysql -u root -p
      • (at the password prompt, enter the password from above)
  • At the '>' MariaDB/MySQL prompt, enter the following commands (MariaDB/MySQL commands are ended with a ';')
    • CREATE DATABASE mymoodle CHARSET 'utf8mb4';
      • ('mymoodle' is the name of the database you would like to use, it will be entered to the Moodle 'config.php' later)
    • GRANT SELECT,INSERT,UPDATE,DELETE,CREATE,CREATE TEMPORARY TABLES,DROP,INDEX,ALTER ON mymoodle.* TO moodleuser@localhost IDENTIFIED BY 'moodlepass';
      • (as above, 'mymoodle', 'moodleuser' and 'moodlepass' will be entered to the Moodle 'config.php' later)
    • flush privileges;
    • quit
  • (! Consider MariaDB/MySQL security - not covered here. If you run a firewall, you don't have too much to worry about.)

Moodle

(I will install under /usr/moodle, data in /usr/moodle_data)

Download

  • Download your favourite version of Moodle from moodle.org (.zip archive is easiest)
  • as Root create folder under /usr and copy zip
    • su
    • mkdir /usr/moodle
    • mkdir /usr/moodle_data
    • cp moodle_111.zip /usr/moodle
  • If you prefer you can install the GIT version directly for all the latest features. Instead of downloading and copying the zip file. See Git_for_Administrators for details.
  • Or if you prefer you can install the CVS version directly for all the latest features. Instead of downloading and copying the zip file.
    • cd /usr/moodle
    • cvs -d:pserver:anonymous@uk.cvs.moodle.org:/cvsroot/moodle login
    • cvs -z3 -d:pserver:anonymous@uk.cvs.moodle.org:/cvsroot/moodle co moodle

Unpack and set file permission etc

  • Still as root we unpack moodle and rename to something appropiate (I have multiple moodle installs, hence this setup). I will call this install mymoodle.
    • cd /usr/moodle
    • unzip moodle_xxx.zip
    • mv moodle mymoodle
      • (optional step - I have more than one install under /usr/moodle)
    • mkdir /usr/moodle_data/mymoodle
      • (same name as the moodle install above)
    • chown -R apache:apache /usr/moodle
      • (! Giving Apache full rights to your Moodle programs is not secure. Check out the forums for recomendations on how to secure a production environment.)
    • chown -R apache:apache /usr/moodle_data

Setup config.php

  • Still as root copy and edit the config file, you should know the host/domain name for your server
    • cd /usr/moodle/mymoodle
    • cp config-dist.php config.php
    • vi config.php (or whatever your favourite editor is!)
  • Your config.php settings should be something like...
    • dbtype = "mariadb" (use "mysqli" for MySQL)
    • dbhost = "localhost"
    • dbname = "mymoodle"
    • dbuser = "moodleuser"
    • dbpass = "moodlepass" (<-- better make this something of your own)
    • prefix = ""
      • (keep the default 'mdl_' prefix if you plan on sharing the database with other applications)
    • wwwroot = "http://myhost.mydomain/mymoodle"
      • (If you only want to try moodle out and will not be accessing it from other machines you can use "http://localhost/mymoodle")
    • dirroot = '/usr/moodle/mymoodle'
    • dataroot = '/usr/moodle_data/mymoodle'
  • Save your changes and exit from the editor

Apache

  • Install it if it's not installed already.
yum install httpd
or everything
yum install httpd*
  • Start it and make it auto-start after reboot:
service httpd start; chkconfig httpd on
  • Open a web browser and make sure you can connect to the installed web server and default port (80) of the server. If not OK, it may be blocked by the firewall (see above). Correct the problem before continuing.
  • Edit the Apache configuration file
    /etc/httpd/conf/httpd.conf
  • Right at the end of the file add the following lines:
    • <Directory "/usr/moodle/mymoodle"> (the directory used during Moodle installation)
    • DirectoryIndex index.php
    • AcceptPathInfo on
    • AllowOverride None
    • Options None
    • Order allow,deny
    • Allow from all
    • </Directory>
    • Alias /mymoodle "/usr/moodle/mymoodle"
  • Don't insert a space in "allow,deny" (common mistake!)
  • You might also want to run through the rest of the config file and make some other (obvious) changes - administrator email and suchlike. Not vital though.
  • Run the Services application (same as for Mysql) - tick and start "httpd", then save changes and exit.

PHP

  • Install the version of PHP you need (7.2 in this case).
yum install php72 php72-php php72-php-xml php72-php-xmlrpc php72-php-mysqlnd php72-php-zip php72-php-gd php72-php-intl php72-php-mbstring php72-php-soap php72-php-opcache
  • Check the installed PHP version:

You may need to create a link to the php executable:

# ln -s /opt/rh/rh-php70/root/bin/php /bin/php
# php -v
  • Create a "phpinfo.php" file within the "/var/www/html" directory (or anywhere the Apache "DocumentRoot" points to) with the following content:
<?php
phpinfo();
?>

And then open web browser and browse to "http://webserver/phpinfo.php" to make sure PHP is working with the web server. Then remove the file.

RedHat EL - or 'the upstream vendor' if you are using a clone - will not introduce newer PHP packages unless there is an exception (php53 in EL5.6+). Moodle has quite a some PHP dependencies which cannot be fullfilled solely by installing all RHEL-provided packages.

You have therefore to make a choice:

  • Use RH and pay attention your Moodle version supports it + PHP modules from and maintain them on your own
  • Install the whole (latest) PHP from source on your own (and maintain it)
  • Install PHP packages from a third party repo (but you won't get support from Redhat if you run into problems):
    • [rpms.famillecollet.com] Maintains recent MySQL and PHP packages for supported EL version (a EPEL contributor)
    • RPMFusion and others also have newer PHP packages

Set up the cron job

As root user edit the /etc/crontab file using vi (or another editor) OR you can add a line to the root user's "personal" crontab (don't do both!).

CLI version

Note: According to Moodle's documentation, users should use the CLI version if possible, as the web version may be removed in future.[7]


  • If you wish to place an entry in your root user's crontab use:
    • crontab -e
    • Add the following line:
 */5 * * * * /usr/bin/php /path/to/mymoodle/admin/cli/cron.php

to run the command every 5 minutes.

Web version

Note: Use the CLI version if possible.


  • If you wish to place an entry in your root user's crontab use:

---

  • If you wish to add an entry in /etc/crontab:
  • Open the /etc/crontab file in an editor (vi).
  • Add the following line:

---

  • In either case, don't forget to save the file and exit (in vi that is <Esc>, then ':wq')

Try your new installation

http://myhost.mydomain/mymoodle/admin

or, if you are running the browser on the same machine

http://localhost/mymoodle/admin

Setting Apache Document Root

If you want the web site to be served as http://www.whatever.com/ instead of http://www.whatever.com/mymoodle, edit
/etc/httpd/conf/httpd.conf

Change From: DocumentRoot /var/www/html

Change To: DocumentRoot /var/www/html/mymoodle

Remember to modify the Moodle 'config.php' file and cron job accordingly.

See also