Closed Linux Slackware 14.2 - cannot access mysql database server from web server

[Well1AmNichtDiePerson]

Sumusubok ako mag-setup ng web server, at database server gamit ang virtualbox.
Ang host OS ko ay Windows 10 x64. Ang Guest OS ko ay Windows 7 x86 web development, slackware x86 web server, at slackware x86 database server.

Ang problema ay hindi ko ma-access ang database server from web server. Parang naka-block ang web server sa database server.

Ito ang status ng server setup ko.
web server
- linux basic setup, basic network setup, enabled php
- ip: 176.18.10.10

database server
- linux basic setup, basic network setup, mysql database
- ip: 176.18.10.11
- uid: testwebuser
- pwd: testwebpwd
- db: crud_db

Windows 7 x86 web development setup
- ip: 176.18.10.12
- notepad++ (can access web server thru virtualbox shared folder feature)
- mysql browser (can access database server - can do add/edit/delete/update)
- chrome (can access URL in web server)
- php script: connect_db.php
pdo("mysql:host=176.18.10.11;dbname=crud_db", "testwebuser", "testwebpwd");

Salamat sa magre-reply.

 

[gabotron]

Baka sa localhost lang ng database server naka-allow ang user. Dapat may access rin ang user from the web server IP, 176.18.10.10:

- from phpMyAdmin of (database server):


- or from terminal of database server:

$ mysql -u root -p
mysql> GRANT ALL PRIVILEGES ON crud_db.* TO 'testwebuser'@'176.18.10.10' IDENTIFIED BY 'testwebpwd';
mysql> FLUSH PRIVILEGES;

- kung may mysql client ka sa web server, test mo ang connectivity from the terminal:

$ mysql -u testwebuser -h 176.18.10.11 -p
Enter password:
Welcome to the MySQL monitor.
...
mysql>

 

[Well1AmNichtDiePerson]

mysql browser:

SQL Query:
select host, user from mysql.user where user = 'testwebuser'

Output
host | user
% | testwebuser

 

[gabotron]

Test mo connectivity from the web server itself. Baka may firewall ang Slackware by default, at naka-block ang port 3306 ng database server.

- kung may telnet client ang web server:

telnet 176.18.10.11 3306

- or use the mysql command as stated previously kung may mysql client ang web server

 

[Well1AmNichtDiePerson]

hindi ko nilagyan ng mysql ang web server kasi ang setup ko ay hiwalay ang web server sa database server.

Pero Ok lang. Nasa development lang naman ako. i-try ko mag-setup ng mysql for testing lang.

Pero paano kapag ang server ay pang-production, kailangan ko pa rin bang mag-install ng mysql sa web server para sa testing ng connectivity???? hindi ba pwede ang php script para sa testing ng mysql connection???

 

[gabotron]

Hindi mysql-server ang pinapa-install sa iyo. mysql client lang para ma-invoke mo ang "mysql" command from the web server. Kung sa CentOS o Debian/Ubuntu yan, isang simpleng command lang. Isang binary lang yan:

# yum install mysql

# apt install mysql

 

[Well1AmNichtDiePerson]

Test mo connectivity from the web server itself. Baka may firewall ang Slackware by default, at naka-block ang port 3306 ng database server.

- kung may telnet client ang web server:

telnet 176.18.10.11 3306

- or use the mysql command as stated previously kung may mysql client ang web server

terminal:

# telnet 176.18.10.11

trying 176.18.10.11...
telnet: connect to address 176.18.10.11: No route to host

# telnet 176.18.10.11 3306

trying 176.18.10.11...
telnet: connect to address 176.18.10.11: No route to host

sinubukan ko ping... destination unreachable....

 

[Well1AmNichtDiePerson]

Nakita ko na ang mali sa setup ko.

web server
- Virtual Machine Adapter setup
- Bridge Adapter (LAN) -> changed to NAT Network

database server
- Virtual Machine Adapter setup
- NAT Network

Windows 7 x86 web development setup
- Virtual Machine Adapter setup
- NAT Network
- Bridge Adapter (LAN)

 

[Well1AmNichtDiePerson]

terminal:

# telnet 176.18.10.11

trying 176.18.10.11...
telnet: connect to address 176.18.10.11: Connection refused

# telnet 176.18.10.11 3306

trying 176.18.10.11...
Connected to 176.18.10.11.
Escape character is '^]'.
Y
blahblahblah....some gibrish...Connection closed by foreign host.

OK na rin ang ping....

 

[gabotron]

Open ang 3306. Try mo using mysql command kung maka-connect ka from the web server.

 

[Well1AmNichtDiePerson]

Mga lodi, maraming salamat sa assitance...

 

[Well1AmNichtDiePerson]

Sunod naman gagawin ko ay securing /hardening ng web server at database server.

Makahingi nga po ng advise sa inyo mga lodi kung paan ito ma-achieve. Salamat....

 

[Well1AmNichtDiePerson]

Open ang 3306. Try mo using mysql command kung maka-connect ka from the web server.

Connected na sa wakas ang web server sa database server.

php test script:
$test_query = "SHOW TABLES FROM $dbname";

browser:
11 tables found....

 

[gabotron]

Sa database server, lock ko lang lahat ng ports via firewall - iptables sa CentOS 7/Ubuntu 18.04 or nftables via firewalld sa CentOS 8/Ubuntu 20.04. Access list lang para ma-specify ko ang allowed IP's.

Sa Apache web server, pwede mo follow 'to: https://geekflare.com/apache-web-server-hardening-security/

Usually okay na ako sa:

TraceEnable off
ServerTokens Prod
ServerSignature Off

Sa nginx, add lang ako server_tokens off; sa main nginx.conf config, okay na.

Actually, di na uso itong mga monolithic setups. Masyadong ma-trabaho. Mas mabilis sa Docker ang LAMP/LEMP setups (Apache/Nginx, MariaDB/MySQL, PHP/PHP-FPM). Wala ka pang aalahanin sa connectivity o sa multiple VM's.