OPS345 Lab 4

THIS PAGE IS A DRAFT, NOT A REAL COURSE PAGE

The current schedule for OPS345 is here: OPS335_Weekly_Schedule

• Data that is often modified is typically stored in a database.
• AWS provides database services via RDS, though you could install your own DBMS like MariaDB on your own VM.
• In the AWS console go to RDS. Create ops345db, with a long password that's different from other passwords. Put it in ops345sgprivate. This one will be used/seen in plain text sometimes.
  • It will complain about not having two subnets in different availability zones.
• In VPC/Subnets, create a new one in vpc-ops345 named subnet2-ops345, in us-east-1b instead of 1a. 10.3.45.128/25
• Go back and try again to create the database.
• Assign temporary elastic IP to yum install mariadb, no need for server.
  • Will disassociate and release the elastic ip at the end of the lab.
• Do the rest of the lab as the regular user, don't use root.
• In the AWS Console go to RDS, and find the FQDN ("Endpoint") for the database. Such as ops345db.cobdogt5aykb.us-east-1.rds.amazonaws.com - record that.
• Try to connect: mysql -u root -plongdbpassword -h ops345db.cobdogt5aykb.us-east-1.rds.amazonaws.com
  • It won't work, the firewall (SG) won't allow it. Modify ops345sgprivate to allow incoming TCP port 3306 (MySQL) from ops345sgprivate.
• Should be able to log in now. If you get something like this: "ERROR 1045 (28000): Access denied for user 'root'@'10.3.45.11' (using password: YES)" then double-check the master username under RDS/ops345db/Configuration and you can reset the password via Modify (might take a few minutes to propagate).
  • See also https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_Troubleshooting.html
• Most mysql commands need to have a semicolon at the end.
• The mysql commandline is nothing like the linux shell. Have to use mysql (or plain SQL) commands.
• Out of the box show databases; shows 4 databses, all of which are used internally by mysql, they are not for you to store data.
• use mysql; show tables; select * from user; select user from user;
• mysql root is not the same as the linux root, but it is an administrator and you should only use it for creating users, databases, and assigning permissions.
• Typically you would use something like this: " MariaDB> grant all privileges on DATABASE_NAME.* TO 'USER_NAME'@'%' identified by 'PASSWORD'; " but that won't work on AWS RDS because your root user doesn't have ALL PRIVILEGES, so can't grant them to another user.
• Instead create a user first: CREATE USER 'andrewdb'@'%' IDENTIFIED BY 'andrewdbpassword';
• Find what privileges your root has: show grants for 'root';
• Give the most important ones to your db user: " GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE ON firstdb.* TO 'andrewdb'@'%'; "
• Log out from root
• mysql -u andrewdb -pandrewdbpassword -h ops345db.cobdogt5aykb.us-east-1.rds.amazonaws.com
• show databases; - note that the list is shorter.
• use firstdb;
• show tables;
• Create tables, insert data, select: https://www.guru99.com/mariadb-tutorial-install.html#6
• A realistic use case for your career: download and instal nextcloud.
• wget the .tar.bz2 (not zip)
• Extract it into /var/www/html so you have a /var/www/html/nextcloud/index.html
• https://docs.nextcloud.com/server/latest/admin_manual/installation/source_installation.html
  • As root, vi /etc/httpd/conf.d/nextcloud.conf

    Alias /nextcloud "/var/www/html/nextcloud/"
    
    <Directory /var/www/html/nextcloud/>
      Require all granted
      AllowOverride All
      Options FollowSymLinks MultiViews
    
      <IfModule mod_dav.c>
        Dav off
      </IfModule>
    </Directory>

  • chown -R apache.apache nextcloud/
  • Get an error:

    This version of Nextcloud requires at least PHP 7.3
    You are currently running 5.4.16. Please update your PHP version.

  • amazon-linux-extras | grep php
  • amazon-linux-extras enable php7.4
  • yum clean metadata
  • yum install php-cli php-pdo php-fpm php-json php-mysqlnd
  • restart apache
  • Get module errors from website, install them:
    • amazon-linux-extras enable httpd_modules
    • yum install php-dom php-gd php-mbstring
  • Should now let you continue the setup.
  • Create an admin account. Use ops345admin/nextcloudadminpass
  • Create a new database and user and password nextclouddb/nextclouduser/nextclouddbpassword
    • CREATE DATABASE nextclouddb;
    • CREATE USER 'nextclouduser'@'%' IDENTIFIED BY 'nextclouddbpassword';
    • GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE ON nextclouddb.* TO 'nextclouduser'@'%';
  • Fill in the database details in the nextcloud web setup screen.
  • Look around inside the nextcloud, create user yoursenecaid, unlimited quota
  • Log in as yoursenecaid, upload a picture, share a link to it.
• When done with everything, release the elastic ip.
• Confirm that everything still works.
• As an extra challenge: get rid of the index.php in the URLs.