Install and configure a distributed software system that uses the LAMP stack (Linux, Apache web server, MySQL/MariaDB, and PHP).
You will install and configure a web application called WordPress, a popular Content Management System (CMS), on two different VM instances where the first one hosts the web server and the second one hosts the database server.
ssh-keygen and upload your public key into the cloud. Please refer to this lecture note for more information.man.lsblk – list block devicesblkid – list block device attributes such as uuid.mkfs – build a Linux filesystemfile – determine file typecp -a <source> <target> – Copy the source directory recursively while preserving all file attributes (mode/permission bits, ownership, and timestamps) into the target directory.ssh -i /path/to/your/private/key/file azureuser@public-ip-or-DNS-name
lsblk to list all available devices:lsblk
lsblk
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
loop0 7:0 0 63.9M 1 loop /snap/core20/2182
loop1 7:1 0 91.9M 1 loop /snap/lxd/24061
loop2 7:2 0 40.4M 1 loop /snap/snapd/20671
sda 8:0 0 30G 0 disk
├─sda1 8:1 0 29.9G 0 part /
├─sda14 8:14 0 4M 0 part
└─sda15 8:15 0 106M 0 part /boot/efi
sdb 8:16 0 4G 0 disk
└─sdb1 8:17 0 4G 0 part /mnt
sdc 8:32 0 4G 0 disk sda with a partition called sda1 mounted on the root file system (/). The additional/external disk volume that we provisioned and attached to the VM is called sdc and it is not mounted on the filesystem yet as listed in the MOUNTPOINT column.sudo file -s /dev/device_name
/dev/xvdf: data
/dev/sdc: Linux rev 1.0 ext4 filesystem data, UUID=de3819b8-068f-48f2-a11e-e6483e10705f (extents) (64bit) (large files) (huge files)
Format the disk with a single ext4 file system:
The following command assumes that you're going to mount and format an empty disk. If your disk has data, then skip this step. If you do not, you'll end up formatting the wrong disk and erasing all existing data. There's no way you can undo this operation easily. You have been warned!
sudo mkfs -t ext4 /dev/device_name
This command should have resulted in an output similar to the one below:
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
524288 inodes, 2097152 blocks
104857 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2147483648
64 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632
Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done
sudo mkdir -p /mnt/disk-1
sudo mount /dev/device_name /mnt/disk-1
/etc/fstab file. It’s strongly advised to use the UUID (Universally Unique Identifier) in the /etc/fstab file to reference the drive, instead of the device name (like /dev/sdc). This practice helps prevent the wrong disk from being mounted at a specific location if the operating system encounters a disk error during boot. The remaining data disks could then receive those same device IDs. To identify the UUID of the new drive, you will use the blkid utility.sudo blkid
/dev/sda1: LABEL="cloudimg-rootfs" UUID="8b0c6e4a-0cab-4db1-83d8-62ef36ce6e95" TYPE="ext4" PARTUUID="8bc09b18-d521-4996-9501-2d20068dc767"
/dev/sda15: LABEL_FATBOOT="UEFI" LABEL="UEFI" UUID="CFA6-63A2" TYPE="vfat" PARTUUID="be89ef0d-74a9-44dc-bfc9-90f1e1d964ce"
/dev/sdb1: UUID="879cbb90-4683-431a-84aa-e671e16f98c9" TYPE="ext4" PARTUUID="0b529588-01"
/dev/sdc: UUID="de3819b8-068f-48f2-a11e-e6483e10705f" TYPE="ext4"
/dev/loop0: TYPE="squashfs"
/dev/loop1: TYPE="squashfs"
/dev/loop2: TYPE="squashfs"
/dev/sda14: PARTUUID="fad88384-86a5-4764-8de3-d490c101b231"/etc/fstab file, but before that it’s recommended that you backup the original file before edit it. This is important because improperly editing the /etc/fstab file could result in an unbootable system.:sudo cp /etc/fstab /etc/fstab.orig
/etc/fstab file using any text editor, such as nano (e.g., sudo nano /etc/fstab).<device-name> with the uuid of the disk (e.g., “de3819b8-068f-48f2-a11e-e6483e10705f”).UUID=<put-the-uuid-here> /mnt/disk-1 ext4 defaults,nofail 1 2
So, this line means mount the filesystem with given UUID at /mnt/disk-1, using the ext4 filesystem type and the default options, plus nofail. Allow dump to backup this filesystem, and check this filesystem at boot time after the root filesystem.
Explanation:
UUID=de..: This is the UUID of the disk obtained from the blkid utility./mnt/disk-1: This is the mount point on the filesystem.ext4: This is the filesystem of the disk.defaults,nofail: These are the mount options. defaults means to use the default options. nofail means to not report errors for this device if it does not exist.1: This is the dump field, which controls whether the dump utility will backup this filesystem. 1 means it will be backed up, and 0 means it won’t.2: This is the pass field, which controls the order in which filesystem checks are done at boot time. The root filesystem should have 1, and other filesystems such as disk volumes should have 2.Save the file and exit your text editor
sudo apt update
sudo apt upgrade -y
sudo apt install mariadb-server mariadb-client
sudo systemctl start mariadb
sudo systemctl status mariadb
We need to change the default data directory of MariaDB into a directory on the external disk we mounted in the previous step:
sudo systemctl status mariadb
$ sudo systemctl status mariadb
mariadb.service - MariaDB 10.3.39 database server
Loaded: loaded (/lib/systemd/system/mariadb.service; enabled; vendor >
Active: active (running) since Tue 2024-03-12 18:55:04 UTC; 2h 13min >
Docs: man:mysqld(8)
https://mariadb.com/kb/en/library/systemd/
Main PID: 24522 (mysqld)
Status: "Taking your SQL requests now..."
Tasks: 30 (limit: 1002)
Memory: 82.9M
CGroup: /system.slice/mariadb.service
└─24522 /usr/sbin/mysqldTake note of the process name that is shown above as Main PID: 24522 (mysqld). Here, the process name is mysqld. If you get a different process name such as mariadbd, then please replace mysqld with mariadbd for the subsequent steps.
ps aux | grep mysqld
The output should look like:
mysql 22844 0.0 11.2 1251744 97156 ? Ssl 18:14 0:00 /usr/sbin/mysqld
azureus+ 23755 0.0 0.0 8168 724 pts/0 S+ 18:24 0:00 grep --color=auto mysqldThe first line shows that the process mysqld is running under the user mysql. This means there’s a user account named mysql that runs the mysqld process. Similarly, if you get a different username such as mariadb, then please replace mysql with mariadb for the subsequent steps.
sudo systemctl stop mariadb
sudo systemctl status mariadb
You should see in the output that the status is “MariaDB server is down” 4. Create a new data directory for the database server to use:
sudo mkdir /mnt/disk-1/db-data
mariadb, then please replace mysql with mariadb as stated above.):sudo chown mysql:mysql /mnt/disk-1/db-data
cp with the -p option.sudo cp -R -p /var/lib/mysql /mnt/disk-1/db-data
/etc/mysql/mariadb.conf.d/50-server.cnfsudo nano /etc/mysql/mariadb.conf.d/50-server.cnf
datadir and change it to the new path:. . .
datadir = /mnt/disk-1/db-data/mysql/
. . .
Note: If datadir starts with # that means it’s commented. Please remove the # to uncomment it.
sudo systemctl start mariadbsudo mysql -u root
select @@datadir;MariaDB [(none)]> select @@datadir;
+----------------------------+
| @@datadir |
+----------------------------+
| /mnt/disk-1/db-data/mysql/ |
+----------------------------+
1 row in set (0.000 sec)
exit and hit Enter to exit.Install the apache HTTP Server (httpd) web server on the web server instance.
sudo apt update
sudo apt install apache2
sudo systemctl status apache2
sudo systemctl start apache2
apache2 processps aux | grep apache2
root 5692 0.0 0.9 6676 3212 ? Ss 07:19 0:00 /usr/sbin/apache2 -k start
www-data 5694 0.0 1.2 752892 4464 ? Sl 07:19 0:00 /usr/sbin/apache2 -k start
www-data 5695 0.0 0.9 752820 3236 ? Sl 07:19 0:00 /usr/sbin/apache2 -k start
azureus+ 6143 0.0 0.1 8168 656 pts/0 S+ 07:42 0:00 grep --color=auto apache2
Here the default user that is running apache2 web server is www-data.
sudo mkdir /mnt/disk-1/www/
sudo chown www-data:www-data /mnt/disk-1/www/
Change the document root directory of the Apache web server to point to the new directory instead of the default directory (/var/www). Edit two configuration files at /etc/apache2/sites-available/000-default.conf and /etc/apache2/apache2.conf using a text editor:
sudo nano /etc/apache2/sites-available/000-default.conf/var/www so change it to /mnt/disk-1/www.<VirtualHost *:80>
ServerAdmin webmaster@localhost
DocumentRoot /mnt/disk-1/www
. . .
sudo nano /etc/apache2/apache2.conf and modify the <Directory> directive from /var/www into /mnt/disk-1/www <Directory /mnt/disk-1/www>
Options Indexes FollowSymLinks
AllowOverride None
Require all granted
</Directory>
Restart the Apache HTTP Server and make sure it is running.
sudo systemctl restart apache2
sudo systemctl status apache2
We need to install PHP version 7.4 or greater as per the system requirement of WordPress.
sudo apt update
sudo apt install -y php7.4 libapache2-mod-php7.4 php7.4-mysql php7.4-gd
php -v
PHP 7.4.3-4ubuntu2.20 (cli) (built: Feb 21 2024 13:54:34) ( NTS )
Copyright (c) The PHP Group
Zend Engine v3.4.0, Copyright (c) Zend Technologies
with Zend OPcache v7.4.3-4ubuntu2.20, Copyright (c), by Zend Technologies
curl -LO http://wordpress.org/latest.tar.gz
tar xvzf latest.tar.gz
sudo cp -av wordpress/* /mnt/disk-1/www/
sudo mkdir /mnt/disk-1/www/wp-content/uploads
www-data), so the web pages can be accessed by the apache web server.sudo chown -R www-data:www-data /mnt/disk-1/www/
It’s always a good security practice to use private IP addresses for communication between VMs in the same network. This way, the traffic doesn’t go over the internet and is not exposed to external threats.
3306. We need to make sure that the db instance server VM’s network/firewall settings allows inbound traffic on 3306 port from the web server VM’s private IP address./etc/mysql/mariadb.conf.d/50-server.cnf and set the bind-address to 0.0.0.0 or commented it out.bind-address directive to 0.0.0.0:sudo nano /etc/mysql/mariadb.conf.d/50-server.cnf
bind-address = 0.0.0.0
sudo systemctl restart mariadb
sudo systemctl status mariadb
10.0.0.0/24)3306 and click addcd /mnt/disk-1/www/
sudo cp -a wp-config-sample.php wp-config.php
wp-config.php in your text editor:sudo nano wp-config.php
Change the database name, database username, and password. We also need to change the default hostname from localhost into the private ip address of your db instance (assuming both instances are in the same region and private network).
// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define('DB_NAME', 'wpdb');
/** MySQL database username */
define('DB_USER', 'wpuser');
/** MySQL database password */
define('DB_PASSWORD', 'wppassword');
/** MySQL hostname */
define('DB_HOST', 'put-the-private-ip-of-db-instance-here');
When we have a web server and a database server, it's important to encrypt data at rest (via data encryption) and in transit (via SSL). It's also important to restrict the communication between the database server and web server to only over a private network, because you don't need to allow access over the public Internet.
wp-config.php, scroll down and copy the link from the config file (https://api.wordpress.org/secret-key/1.1/salt/) to generate authentication unique keys and salts. Copy the generated keys and add them to the config file.define( 'AUTH_KEY', 'put your unique phrase here' );
define( 'SECURE_AUTH_KEY', 'put your unique phrase here' );
define( 'LOGGED_IN_KEY', 'put your unique phrase here' );
define( 'NONCE_KEY', 'put your unique phrase here' );
define( 'AUTH_SALT', 'put your unique phrase here' );
define( 'SECURE_AUTH_SALT', 'put your unique phrase here' );
define( 'LOGGED_IN_SALT', 'put your unique phrase here' );
define( 'NONCE_SALT', 'put your unique phrase here' );
wp-config.php in the previous step.sudo mysql -u root
CREATE DATABASE wpdb;
USE wpdb;
CREATE USER wpuser@localhost IDENTIFIED BY 'wppassword';
GRANT ALL PRIVILEGES ON wpdb.* TO wpuser@private-ip-web-server-instance IDENTIFIED BY 'wppassword';
FLUSH PRIVILEGES;
exithttp://server_domain_name_or_public_IP/wp-admin/.
Submit your answers with screenshots showing the commands you executed as a PDF file by the due date.
Lab submissions are due one hour before the next week’s lab begins.