Tayyebi

Posted on Sep 25, 2019

Linux as a web server

#centos #devops #webdev #virtualhost

FAQ

Who is this post for?

Those who need some #eli5 step by step notes, to simply configure a web server, to host multiple websites on a single server.

Is this everything about configuring of a web server?

No it's just a tranquilizer to newbie programmers mental challenges on hosting, and rapid Wordpressers who wanna mine money faster!

Spoil it!

Finally you will install Apache, MySQL, BIND, PHP, and etc... on a Linux server and configure it to host multiple domains like a.b.com and d.e.com.

Where to learn theory of everything?

Just Google it with the following keyword: LPIC

Connect to your server!

use ssh <IP> or ssh <Domain> command to connect to your server.
(e.g-> ssh example.com)

Install Apache

What is Apache? Apache serves your content to the world. And also it can give you a hand to create dynamic website with PHP which Wordpress is also a PHP thing.

To install Apache

1- sudo yum install httpd mod_ssl

2- sudo /usr/sbin/apachectl start

If message appears: Starting httpd: httpd: Could not reliably determine the server's fully qualified domain name, using 127.0.0.1 for ServerName, edit the configuration file using vim or any editor you wish (Step 3).

3- sudo vim /etc/httpd/conf/httpd.conf

and bring the following line out of comment:

4- #ServerName www.example.com:80 => ServerName MyServerName (which MyServerName is your own server name!)

Allow Apache in firewall. As you know, Apache listens on port HTTP 80 by default.

5.1- sudo iptables -I INPUT -p tcp --dport 80 -j ACCEPT

5.2- sudo service iptables save

Restart Apache:

6- sudo /usr/sbin/apachectl restart

Test your installation:

7- curl 127.0.0.1

As you know, it's very critical to allow Apache to access your codes!

8- sudo chcon -t httpd_sys_rw_content_t /var/www/html/mysite -R

Learn more about FirewallD

https://www.digitalocean.com/community/tutorials/how-to-set-up-a-firewall-using-firewalld-on-centos-7

Install PHP

Install and enable EPEL repository:

1- sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-7.noarch.rpm

Install and enable Remi repository

2- sudo yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm

Install yum-config-manager

3- yum install yum-utils

Install PHP modules which programmers use to reduce their headache

4- yum install php php-mcrypt php-cli php-gd php-curl php-mysql php-ldap php-zip php-fileinfo

Test the PHP's command line interface (CLI)

5- php -v

Wanna create a secondary sysadmin user? (Sudoer guy)

Create a user

1- ‍‍‍a‍dduser theusername (you say theusername)

Choose a password

2- passwd theusername (you said theusername)

Just like school, anyone is in a group. So you have to add new user to wheel, which is a super user level group:

3- usermod -aG wheel theusername

Switch user

4- su - username

Disable a user login (EMail or FTP accounts maybe)

1- Edit the /etc/passwd

2- Change shell to /bin/nologin

Learn more about configuring FTP server:

https://linuxize.com/post/how-to-setup-ftp-server-with-vsftpd-on-centos-7/

Hey server! KEEP EVERYTHING IN MIND; even "Clean your mind"

Edit ~/.bashrc

1- vim ~/.bashrc

2- Put following lines at the end of the file:

export HISTCONTROL=ignoredups:erasedups  
shopt -s histappend
export PROMPT_COMMAND="${PROMPT_COMMAND:+$PROMPT_COMMAND$'\n'}history -a; history -c; history -r"
export HISTTIMEFORMAT='%F %T '

3- Test it: history

How to install MySQL

Install wget which is more handy tool than curl for heavy downloads.

1- yum install wget

Download the package:

2- wget http://repo.mysql.com/mysql-community-release-el7-5.noarch.rpm

Add the package:

3- sudo rpm -ivh mysql-community-release-el7-5.noarch.rpm

Update package manager:

4- yum update

Install the package:

5- sudo yum install mysql-server

Start daemon:

6- sudo systemctl start mysqld

Configure installation:

7- sudo mysql_secure_installation

Test installation:

8- mysql -u root -p (which root is the root username)

Create a MySQL user:

9- mysql> create user 'testuser'@'localhost' identified by 'mysecretpass'; (username is testuser and the password is mysecretpass)

Grant permissions to user:

10- mysql> grant all on databasename.* to 'testuser' identified by 'mysecretpass'; (replace databasename with the database name)

WhatIsMyIP?

If ifconfig doesn't work:

use: ip addr show

Change hostname

Configuration file is located in /etc/sysconfig/network. So open it in editor and find the related line:

HOSTNAME=myserver.domain.com

Also you can change the host that is associated with the main IP address for your server in /etc/hosts file.

Test command: hostname

Carefully restart networking (You may lose your connection to remote server!): /etc/init.d/network restart

BIND DNS (Domain Name Server: The magic behind mycustomcomputername.com)

You can check each domain's propagation using DNS checkers online. e.g-> https://dnschecker.org/
Also there is a geeky way: nslookup domain.com

Install BIND

1- sudo yum install bind bind-utils -y

Configure BIND (Remember that you can define your zones here, but it's better to keep the standards.

2- sudo cat /etc/named.conf

Look for included files, and edit the file as described below:

3- sudo vi /etc/named.rfc1912.zones

Define your zones in file same as following lines:

zone "mydomain.ir" IN {
    type master;
    file "mydomain.ir.zone";
    allow-transfer { none; };
};

zone "mycustomer1domain.com" IN {
    type master;
    file "customers.zone";
    allow-transfer { none; };
};

zone "mycustomer2domain.com" IN {
    type master;
    file "customers.zone";
    allow-transfer { none; };
};

So you have to create the customers.zone and mydomain.ir.zone files you just mentioned in directory /var/named:

5.1- sudo touch /var/named/customers.zone
5.2- sudo touch /var/named/mydomain.ir.zone

Then edit them as you wish:

$TTL 86400
@   IN  SOA     ns1.mydomain.com. root.mydomain.com. (
        2013042201  ;Serial
        3600        ;Refresh
        1800        ;Retry
        604800      ;Expire
        86400       ;Minimum TTL
)
; Specify our two nameservers
        IN  NS      ns1.mydomain.ir.
        IN  NS      ns2.mydomain.ir.
; Resolve nameserver hostnames to IP, replace with your two droplet IP addresses.
ns1     IN  A       SERVER_IP_HERE
ns2     IN  A       SERVER_IP_HERE

; Define hostname -> IP pairs which you wish to resolve
@       IN  A       SERVER_IP_HERE
www     IN  A       SERVER_IP_HERE

Then any domain that is decided to be hosted on this server, must set ns1.mydomain.ir and ns2.mydomain.ir as their name server in domain control panel. If website was defined as a Virtual Host in Apache, it will be accessible.

Virtual Hosts

Edit the config file: sudo vi /etc/httpd/conf/httpd.conf foreach website you want to host.

<VirtualHost *:80>
   DocumentRoot "/var/www/html/domainname"
   ServerName domainname
   ServerAlias www.domainname
   RedirectPermanent / https://domainname2
</VirtualHost>

Refrence:

https://twitter.com/MRezaTayyebi/status/1152794765164974080
https://support.rackspace.com/how-to/centos-6-apache-and-php-install/
https://www.tecmint.com/install-php-7-in-centos-7/
https://www.digitalocean.com/community/tutorials/how-to-create-a-sudo-user-on-centos-quickstart
https://gist.github.com/tayyebi/5e03f83dff1b897a51e530748d74e872
https://www.linode.com/docs/databases/mysql/how-to-install-mysql-on-centos-7/
https://support.rackspace.com/how-to/centos-hostname-change/
https://www.digitalocean.com/community/tutorials/how-to-install-the-bind-dns-server-on-centos-6
https://httpd.apache.org/docs/2.4/vhosts/examples.html

DEV Community