Coding Bootcamp: Setting-up a Java Web-Server at okeanos

Today's objectives

• Create a VM at ~okeanos
  
• Set-up all required packages
  
• An operatign system [Ubuntu Server 16.04 LTS]
  
• MySQL server
  
• PhpMyAdmin
  
• Apache Tomcat
  
• Learn about servers adrministration (just the tip of the iceberg)

Today's objective

• The blue pill is not a choice...

~okeanos - an Ocean of resources!

• Connect to ~okeanos using the following link:
  https://accounts.okeanos.grnet.gr/ui/
  
• In the LOGIN using choose the CLASSIC ACCOUNT option
  
• Fill in the same email and password that you used to create your account
  
• In order to join an availabe project of ~okeanos follow the link:
  https://accounts.okeanos.grnet.gr/ui/projects
  
• and choose Join a project. In the search area, search for project
  bootcamp2.afdemp.gr
  and ask to join
  
• Wait to be be accepted!

Create your first Virtual Machine!

• At the Cyclades User Interface, click the New Machine+ orange button
  
  
• There are 5 Steps in order to create a VM

Creating a VM - Step 1 (Image)

• From the Images left list select the System
  
• From the Available images on the right list select the Ubuntu Server LST (Ubuntu Server 16.04.2 LTS), and click next
  
  

Creating a VM - Step 2 (Flavor)

• Select, 2x at the CPU, 4 GB at the RAM and 20 GB at the Disk Size
  
• Click the green next button
  
  

Creating a VM - Step 3 (Networking)

• Be sure that you have an Internet (public IPv4) selected.
  
• Create new if necessary!
  
  

Creating a VM - Step 4 (Personalize)

• Fill in a Machine name and click the green next button
  
• No other options are necessary to be filled
  
  

Creating a VM - Step 5 (Confirm)

• Be sure that the settings for your VM are correct and then click the orange create machine button
  
  
  
• Caution!! Save the temporary password that is going to appear after clicking the create machine

Storing the temporary password

• Save the temporary password that appeared on your screen. If you lose this password you have to repeat all steps form the beginning!
  
  

It's alive! - details of your system

Congratulations, your system is up and running!

• At the bottom of the page there is public IPv4 address from which you can connect from everywhere
  
• The default user created with the VM is user and the password the one that you saved at the end of Step 5

Connect to your VM

For Windows, download and run Putty

• Fill the Host Name (or IP address) field with user@your-vm-public-ipv4 and the Port field with 22
  
• Press Open (and Yes if a Putty Alert-Warning window pops up)

Connect to your VM (2)

• For Linux or MacOS devices, open a terminal and use the following command
  ssh
  
• If your connection is declined and you received the following message
  @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
  @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
  @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
  
• Execute the following command
  sudo ssh-keygen -R your-ipv4
  
• If your connection is successful then your terminal will control your VM until you use the following command
  logout

Am I connected?

• If the connection was successful you should see something similar to the following picture

Security - our first priority!

• Let's change the password of the default user
  
• In your terminal type the following command (as shown in the screen-shot)
  passwd
  
• Note that filling the password is not visible on the screen!

Update your system

• It's important to keep your system up to date with the latest updates installed. Update your system by executing the following command in your terminal:
  sudo apt-get -y update && sudo apt-get -y upgrade
  
• Enter your password if asked, and respond "Y" or "y" if asked the following
  Do you want to continue? [Y/n]
  
• Press Enter and wait until the installation is complete (it might take some time!)

Update your system (2)

• Select the second option if you are promted to update the Grub
  Keep the local version currently installed

Update your system (3)

• Select the first option in the Configuring grup-pc screen
  /dev/vda

MySQL server

• In order to install the latest MySQL server in your system execute the following command in your terminal:
  sudo apt-get -y install mysql-server
  
• Enter a password when asked (see the following figure).

Install a Web-Server and a MySQL web-manager

• Execute the following commands in your terminal:
  
• First install the Apache Web-Server
  sudo apt-get -y install apache2
  
• then install PHP
  sudo apt-get -y install php7.0-mysql php7.0-curl php7.0-json php7.0-cgi php7.0 libapache2-mod-php7.0
  
• finally, install phpMyAdmin
  sudo apt-get -y install phpmyadmin

Configure phpMyAdmin

• In the next screen select the apache2 option.
  
• !!Important!! Press space on your apache2 selection. Only if an asterisk (*) is marked on the left of the apache2 proceed with ok

Configure phpMyAdmin (2)

• Select Yes if you are prompted with a pink Configuring phphmyadmin screen
  
• When asked, enter your MySQL root password in the corresponding screen

Connect to your MySQL server remotely

• Access your MySQL server through a Web-Browser at
  http://your-ipv4/phpmyadmin/
  
• Enter your MySQL root credentials in the following form, ang click Go

• If you see raw code (instead of the login page) try the following (next slide)

Connect to your MySQL server remotely (2)

• In a terminal execute the following
  sudo nano /etc/apache2/apache2.conf
  
• Add the following line at the end of the file
  Include /etc/phpmyadmin/apache.conf
  
• Press CTLR + o to save the changes, Enter to verify, and CTRL + x to exit the edit mode
  
• Restart the Apache server
  sudo systemctl restart apache2
  
• reload the phpMyAdmin page

Download Java JDK & Apache Tomcat

• First we need to install the latest Java Development Kit. Execute the following command in the terminal
  sudo apt-get -y install default-jdk
  
• Create a Tomcat group and user for security purpose
  sudo groupadd tomcat;
  sudo useradd -s /bin/false -g tomcat -d /opt/tomcat tomcat
  
• Download Tomcat 8.5 from the following link (it's curl -Omicron! not zero)
  curl -O http://www-eu.apache.org/dist/tomcat/tomcat-8/v8.5.15/bin/apache-tomcat-8.5.15.tar.gz

Install Apache Tomcat

• Create a directory that will store the apache tomcat and unzip the tar.gz that you downloaded earlier in this directory. Execute the following commands
  sudo mkdir /opt/tomcat;
  sudo tar xzvf apache-tomcat-8.5.15.tar.gz -C /opt/tomcat --strip-components=1
  
• Set-up the permissions for Tomcat. Execute the following commands
  cd /opt/tomcat;
  sudo chgrp -R tomcat /opt/tomcat;
  sudo chmod -R g+r conf;
  sudo chmod g+x conf;
  sudo chown -R tomcat webapps/ work/ temp/ logs/

Configure Apache Tomcat

• In your terminal execute the following command to edit the tomcat.service file
  sudo nano /etc/systemd/system/tomcat.service
  
• Copy-paste the following text in the file (erplace the existing)

[Unit]
Description=Apache Tomcat Web Application Container
After=network.target

[Service]
Type=forking

Environment=JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-amd64/jre
Environment=CATALINA_PID=/opt/tomcat/temp/tomcat.pid
Environment=CATALINA_HOME=/opt/tomcat
Environment=CATALINA_BASE=/opt/tomcat
Environment='CATALINA_OPTS=-Xms512M -Xmx1024M -server -XX:+UseParallelGC'
Environment='JAVA_OPTS=-Djava.awt.headless=true -Djava.security.egd=file:/dev/./urandom'

ExecStart=/opt/tomcat/bin/startup.sh
ExecStop=/opt/tomcat/bin/shutdown.sh

User=tomcat
Group=tomcat
UMask=0007
RestartSec=10
Restart=always

[Install]
WantedBy=multi-user.target

Configure Apache Tomcat (2)

• Press CTLR + o to save the changes, Enter to verify, and CTRL + x to exit
  
• Allow traffic to port 8080 used by Apache Tomcat by executing the following command
  sudo ufw allow 8080
  
• Restart Tomcat and set to open on start-up
  sudo systemctl stop tomcat;
  sudo systemctl start tomcat;
  sudo systemctl enable tomcat;
  
• Check if Tomcat is running and listening to the 8080 port. In a web-browser open:
  http://your-ipv4:8080
  
• If everything is fine you should see a web-page like the one in the next slide!

Configure Apache Tomcat (3)

Configure Apache Tomcat (4)

• In order to access the manager-gui and the admin-gui we need to provide credentials at the tomcat-users xml file:
  sudo nano /opt/tomcat/conf/tomcat-users.xml
  

• Add the following line (with your own "admin" and "password" credentials)

  <user username="admin" password="password" roles="manager-gui,admin-gui"/>

  after the (replace the green line)
  
  
  

• Press CTLR + o to save the changes, Enter to verify, and CTRL + x to exit

Configure Apache Tomcat (5)

• In order to allow external access to the manager-gui and the admin-gui we should edit the context xml file, by executing the following command:
  sudo nano /opt/tomcat/webapps/manager/META-INF/context.xml
  
• Navigate to the file until you find the following entry
  
  
  
  
• Comment the element by adding <!-- at the beginning and --> at the end, like:
  
  
  

Configure Apache Tomcat (6)

• Press CTLR + o to save the changes, Enter to verify, and CTRL + x to exit
  
• Make the same changes as in the previous file to the following context xml file by executing the command
  sudo nano /opt/tomcat/webapps/host-manager/META-INF/context.xml
  

• Restart tomcat

  sudo systemctl restart tomcat

Testing Apache Tomcat

• Access your tomcat web-api from a web browser from the following link http://your-ipv4:8080
  
• Make sure that Manager App and Host Manager pages are accessible
  
• When asked for credentials, provide those that you selected in slide "Configure Apache Tomcat (4)"

Export your local database

• Open the MySQL Workbench, connect to your local database and then go to the Menu Server-->Data Export

Export your local database (2)

• In the Objects Selection tab, select the schema that you want to Export
  
• Be sure that the Include Create Schema check box at the bottom is checked and press Start Export
  
• Click "Continue Anyway" if you get a mysqldump Version Mismatch Warning

Upload your database

• Open the PhpMyAdmin of your VM from a browser
  http://you-ipv4/phpmyadmin/
  
• Enter your MySQL credentials and click go
  
• From the top-menu select Import like in the screen-shot presented in the next slide

Upload your database (2)

Upload your database (3)

• Select Choose file, navigate to the dump file that you exported earlier with MySQL Workbench and select the dump file and then click Go at the end of the page

Export your Java Web Application

• (step 1) be sure that the database credentials in your Java code are the correct for your MySQL at ~okeanos
  con = DriverManager.getConnection("jdbc:mysql://localhost:3306/the_db_name",
  "root", "your_password");

Export your Java Web Application (2)

• Save all changed files and "Right-click" on the Project-->Export-->WAR file
  
• Be sure that (1) is saved in a location that you remember and (2) is optimized for Tomcat 8.0
  
• Click Finish
  

Deploy your Java Web Application

• go to
  http://your-ipv4:8080/manager/html
  
• Enter the credentials that you declared for the Tomcat management if asked
  
• In the WAR file to deploy sub-section of the Deploy section click the Choose File and select the "CodingBootcampJSPExercise1.war" that you exported earlier on your Desktop
  
• Then click Deploy
  
• Soon the page should be refreshed and at the top your Servlet should be visible! (Check the next screen-shot)

Run your Java-Web Application

• Click the /CodingBootcampJSPExercise1 and check if your web-application is alive!
  
• You can Stop, Reload, Undeploy web-applications

Run your Java-Web Application (2)

• In order to redeploy your web-application, first Undeploy and then follow the Deploy the WAR file on the remote server instruction from the beginning.

Hands-on! Exercise

• Port your personal assignment in the Remote Server that you just set up!
  
• Export your local database in a dump file and import it to your remote mysql server through phpMyAdmin UI
  
• Export your Java-web-application to a WAR file and deploy it to the remote apache tomcat server through the Tomcat Web Application Manager
  
• Test the functionalities of your web-app!

Further reading - dive deeper!

• Basic Linux commands (link)
  
• The complete Bash command list (link)
  
• Linux users, groups and permissions (link)
  
• A basic MySQL-server tutorial (link)
  
• How to make your Linux server more secure (link)
  
• 20 Linux Server Hardening Security Tips (advanced) (link)