The Perfect Server CentOS 7.6 with Apache, PHP 7.2, Postfix, Dovecot, Pure-FTPD, BIND and ISPConfig 3.1

This tutorial shows the installation of ISPConfig 3.1 on a CentOS 7.6 (64Bit) server. ISPConfig is a web hosting control panel that allows you to configure the following services through a web browser: Apache web server, PHP 7.2, Postfix mail server, MySQL, BIND nameserver, PureFTPd, SpamAssassin, ClamAV, Mailman, and many more.

1 Requirements

To install such a system you will need the following:

• A Centos 7.6 minimal server system. This can be a server installed from scratch as described in our Centos 7 minimal server tutorial or a virtual-server or root-server from a hosting company that has a minimal Centos 7.6 setup installed.
• A fast Internet connection.

2 Preliminary Note

In this tutorial, I use the hostname server1.example.com with the IP address 192.168.0.100 and the gateway 192.168.0.1. These settings might differ for you, so you have to replace them where appropriate.

3 Prepare the server

Set the keyboard layout

In case that the keyboard layout of the server does not match your keyboard, you can switch to the right keyboard (in my case "de" for a German keyboard layout, with the localectl command:

localectl set-keymap de

To get a list of all available keymaps, run:

localectl list-keymaps

I want to install ISPConfig at the end of this tutorial, ISPConfig ships with the Bastille firewall script that I will use as the firewall, therefor I disable the default CentOS firewall now. Of course, you are free to leave the CentOS firewall on and configure it to your needs (but then you shouldn't use any other firewall later on as it will most probably interfere with the CentOS firewall).

Run...

yum -y install net-tools
systemctl stop firewalld.service
systemctl disable firewalld.service

to stop and disable the CentOS firewall. It is ok when you get errors here, this just indicates that the firewall was not installed.

Then you should check that the firewall has really been disabled. To do so, run the command:

iptables -L

The output should look like this:

[[email protected] ~]# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination

Chain FORWARD (policy ACCEPT)
target prot opt source destination

Chain OUTPUT (policy ACCEPT)
target prot opt source destination

Or use the firewall-cmd command:

firewall-cmd --state

[[email protected] ~]# firewall-cmd --state
not running
[[email protected] ~]#

Now I will install the network configuration editor and the shell based editor "nano" that I will use in the next steps to edit the config files:

yum -y install nano wget NetworkManager-tui yum-utils

If you did not configure your network card during the installation, you can do that now. Run...

nmtui

... and go to Edit a connection:

Select your network interface:

Then fill in your network details - disable DHCP and fill in a static IP address, a netmask, your gateway, and one or two nameservers, then hit Ok:

Next select OK to confirm the changes that you made in the network settings

and Quit to close the nmtui network configuration tool.

You should run

ifconfig

now to check if the installer got your IP address right:

[[email protected] ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
 inet 192.168.0.100 netmask 255.255.255.0 broadcast 192.168.0.255
 inet6 fe80::20c:29ff:fee5:5b47 prefixlen 64 scopeid 0x20<link>
 inet6 2003:c2:9731:a445:20c:29ff:fee5:5b47 prefixlen 64 scopeid 0x0<global>
 ether 00:0c:29:e5:5b:47 txqueuelen 1000 (Ethernet)
 RX packets 227784 bytes 317714901 (302.9 MiB)
 RX errors 0 dropped 0 overruns 0 frame 0
 TX packets 205574 bytes 23608521 (22.5 MiB)
 TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
 inet 127.0.0.1 netmask 255.0.0.0
 inet6 ::1 prefixlen 128 scopeid 0x10<host>
 loop txqueuelen 1 (Local Loopback)
 RX packets 0 bytes 0 (0.0 B)
 RX errors 0 dropped 0 overruns 0 frame 0
 TX packets 0 bytes 0 (0.0 B)
 TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

[[email protected] ~]#

If your network card does not show up there, then it not be enabled on boot, In this case, open the file /etc/sysconfig/network-scripts/ifcfg-eth0

nano /etc/sysconfig/network-scripts/ifcfg-ens33

and set ONBOOT to yes:

[...]
ONBOOT=yes
[...]

and reboot the server.

Check your /etc/resolv.conf if it lists all nameservers that you've previously configured:

cat /etc/resolv.conf

If nameservers are missing, run

nmtui

and add the missing nameservers again.

Now, on to the configuration...

Adjusting /etc/hosts and /etc/hostname

Next, we will edit /etc/hosts. Make it look like this:

nano /etc/hosts

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
192.168.0.100   server1.example.com     server1

::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

Set the hostname in the /etc/hostname file. The file shall contain the fully qualified domain name (e.g. server1.example.com in my case) and not just the short name like "server1". Open the file with the nano editor:

nano /etc/hostname

And set the hostname in the file.

server1.example.com

Save the file and exit nano.

Set SELinux to permissive

SELinux is a security extension of CentOS that should provide extended security. ISPConfig does not ship with an SELinux rule set, therefore I set it to permissive (this is a must if you want to install ISPConfig later on).

Edit /etc/selinux/config and set SELINUX=permissive:

nano /etc/selinux/config

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=permissive
# SELINUXTYPE= can take one of these two values:
#     targeted - Targeted processes are protected,
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

Afterwards we must reboot the system:

reboot

4 Enable Additional Repositories and Install Some Software

First, we import the GPG keys for software packages:

rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY*

Then we enable the EPEL repository on our CentOS system as lots of the packages that we are going to install in the course of this tutorial are not available in the official CentOS 7 repository:

yum -y install epel-release

Then we update our existing packages on the system:

yum -y update

Now we install some software packages that are needed later on:

yum -y groupinstall 'Development Tools'

5 Quota

(If you have chosen a different partitioning scheme than I did, you must adjust this chapter so that quota applies to the partitions where you need it.)

To install quota, we run this command:

yum -y install quota

Now we check if quota is already enabled for the file system where the website (/var/www) and maildir data (var/vmail) is stored. In this example setup, I have one big root partition, so I search for ' / ':

mount | grep ' / '

[[email protected] ~]# mount | grep ' / '
/dev/mapper/centos-root on / type xfs (rw,relatime,attr2,inode64,noquota)
[[email protected] ~]#

If you have a separate /var partition, then use:

mount | grep ' /var '

instead. If the line contains the word "noquota", then proceed with the following steps to enable quota.

Enabling quota on the / (root) partition

Normally you would enable quota in the /etc/fstab file, but if the filesystem is the root filesystem "/", then quota has to be enabled by a boot parameter of the Linux Kernel.

Edit the grub configuration file:

nano /etc/default/grub

search for the line that starts with GRUB_CMDLINE_LINUX and add rootflags=uquota,gquota to the commandline parameters so that the resulting line looks like this:

GRUB_CMDLINE_LINUX="crashkernel=auto rd.lvm.lv=centos/root rd.lvm.lv=centos/swap rhgb quiet rootflags=uquota,gquota"

and apply the changes by running the following command.

cp /boot/grub2/grub.cfg /boot/grub2/grub.cfg_bak
grub2-mkconfig -o /boot/grub2/grub.cfg

and reboot the server.

reboot

Now check if quota is enabled:

mount | grep ' / '

[[email protected] ~]# mount | grep ' / '
/dev/mapper/centos-root on / type xfs (rw,relatime,attr2,inode64,usrquota,grpquota)
[[email protected] ~]#

When quota is active, we can see "usrquota,grpquota" in the mount option list.

Enabling quota on a separate /var partition

If you have a separate /var partition, then edit /etc/fstab and add ,uquota,gquota to the / partition (/dev/mapper/centos-var):

nano /etc/fstab

#
# /etc/fstab
# Created by anaconda on Sun Sep 21 16:33:45 2014
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/centos-root /                       xfs     defaults        1 1
/dev/mapper/centos-var /var                     xfs     defaults,uquota,gquota        1 2
UUID=9ac06939-7e43-4efd-957a-486775edd7b4 /boot                   xfs     defaults        1 3
/dev/mapper/centos-swap swap                    swap    defaults        0 0

Then run

mount -o remount /var

quotacheck -avugm
quotaon -avug

to enable quota. When you get an error that there is no partition with quota enabled, then reboot the server before you proceed.

6 Install Apache, PHP, MySQL and phpMyAdmin

Enable the Remi repository to get newer PHP versions:

yum install http://rpms.remirepo.net/enterprise/remi-release-7.rpm
yum-config-manager --enable remi-php72

We can install the needed packages with one single command:

yum -y install ntp httpd mod_ssl mariadb-server php php-mysql php-mbstring phpmyadmin

To ensure that the server cannot be attacked through the HTTPOXY vulnerability, we will disable the HTTP_PROXY header in apache globally. 

Add the apache header rule at the end of the httpd.conf file:

echo "RequestHeader unset Proxy early" >> /etc/httpd/conf/httpd.conf

And restart httpd to apply the configuration change.

service httpd restart