Virtual Hosting Howto With Virtualmin On CentOS 5.1

Version 1.0.1 Author: Andrew Colin Kissa <andrew [at] topdog [dot] za [dot] net> Last edited 14/04/2008

Introduction

This tutorial shows how to set up a CentOS 5.x server to offer all services needed by virtual web hosters. These include web hosting, smtp server with (SMTP-AUTH and TLS, SPF, DKIM, Domainkeys), DNS, FTP, MySQL, POP3/IMAP, Firewall, Webalizer for stats.

I will use the following software:

Database Server: MySQL 5.0.22 Mail Server: Postfix 2.3.3 NS Server: BIND9 9.3.3 Web Server: Apache 2.2.3 /PHP 5.1.6 FTP Server: Vsftpd 2.0.5 POP3/IMAP server: Dovecot 1.0 Webalizer: for site statistics 2.01_10 Virtualmin: Control panel

OS Installation

Requirements

To install the system you will need

CentOS 5.1 Install media A good internet connection

Install The Base System

NOTE Some stages of the installation are not described here in interest of keeping the howto short, The grub configuration stages are left out for instance.

Boot from the DVD or CD media and at the boot prompt type linux text. Skip the media test. Select your language:

Select keyboard layout:

Configure your network, I will be using dhcp if you do not have dhcp you can use static entries.

Select Yes to initialize drive:

Select custom layout for partitioning type:

Create partitions:

Configure networking:

Set IP address and netmask:

Set gateway and dns servers:

Set the hostname:

Set the timezone:

Set the root password:

Select server group and select customize software selection:

Package groups select as follows: o DNS name server

bind-chroot

Editors o vim-enhanced

FTP server Mail server

o dovecot o spamassassin o postfix

Mysql Database o mysql-server

Web server o mod_ssl o webalizer o php o php-pear o http-suexec o php-mysql

Start the installation:

File system is formatted:

The installation will run:

Reboot the system:

Services To Disable

To enhance security and free system resources on the system we need to disable any services that are not required. You can run this script to do this for you.

acpid anacron apmd autofs bluetooth cups firstboot gpm haldaemon messagebus mdmonitor hidd ip6tables kudzu lvm2-monitor netfs nfslock pcscd portmap rpcgssd rpcidmapd sendmail smartd yum-updatesd

Basics

We need to fix a few issues to prepare the system for configuration.

Install updates

yum upgrade

Switch the mta to postfix

alternatives --config mta

There are 2 programs which provide 'mta'. Selection Command ----------------------------------------------- 1 /usr/sbin/sendmail.postfix *+ 2 /usr/sbin/sendmail.sendmail Enter to keep the current selection[+], or type selection number: 1

Install caching-nameserver config:

yum install caching-nameserver

Install Build tools:

yum install gcc cpp gcc-c++ automake automake14 automake15 automake16 automake17 openssl-devel subversion ncurses-devel -y

Configure Network Alias

cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth0:1

Modify the file /etc/sysconfig/network-scripts/ifcfg-eth0:1 to look like this: DEVICE=eth0:1 BOOTPROTO=static BROADCAST=192.168.1.255 IPADDR=192.168.1.6 NETMASK=255.255.255.0 NETWORK=192.168.1.0 ONBOOT=yes

Install Webmin / Virtualmin

Import webmin pgp key:

wget http://www.webmin.com/jcameron-key.asc rpm --import jcameron-key.asc

Download the rpm:

wget http://prdownloads.sourceforge.net/webadmin/webmin-1.390-1.noarch.rpm

Verify the rpm (should say OK or else download again):

rpm --checksig webmin-1.390-1.noarch.rpm

Install the rpm:

rpm -Uvh webmin-1.390-1.noarch.rpm

Initial Webmin Config

We need to secure webmin by editing /etc/webmin/miniserv.conf and make the following changes:

Using SSL only:

ssl=1

Change the port to 443 and bind to the second nic only:

port=443 bind=192.168.1.6

Disable UDP broadcasts:

#listen=10000

Change host lockout on login failures to 3 :

blockhost_failures=3

Increase host lockout timeout to 120:

blockhost_time=120

Change user lockout on login failures to 3:

blockuser_failures=3

Change user lockout timeout to 120:

blockuser_time=120

Change the realm to something else:

realm=cpanel

Log logins to utmp:

utmp=1

Install the webmin Tiger theme:

Login to webmin via https://192.168.1.5:10000 using root and your password. Go to webmin ? Configuration ? webmin themes. Select From ftp or http URL and enter http://www.stress-free.co.nz/files/theme-stressfree.tar.gz Click install theme. Click "return to list themes". Select StressFree as the Current theme then click change.

Install php-pear module:

Go to webmin webmin configuration webmin modules. Select Third party module from and enter http://www.webmin.com/download/modules/php-

pear.wbm.gz. Click install module.

Install virtualmin:

Go to webmin webmin configuration webmin modules. Select install from ftp or http URL and enter http://download.webmin.com/download/virtualmin/virtual-

server-3.51.gpl.wbm.gz Click install module.

Remove unwanted modules Go to webmin webmin configuration delete and select the following:

ADSL client Bacula backup system CD Burner CVS Server Cluster change passwords Cluster copy files Cluster cron jobs Cluster shell commands Cluster software packages Cluster usermin servers Cluster users and groups

Cluster webmin servers Command shell Configuration engine Custom commands DHCP server Fetchmail mail retrieval File manager Frox ftp proxy HTTP Tunnel Heartbeat monitor IPsec VPN Jabber IM server LDAP server Logical volume management Majordomo list manager NFS exports NIS client and server OpenSLP server PPP dialin server PPP dialup client PPTP vpn server PPTP vpn client Postgresql database server Printer admin ProFTPD server QMAIL mail server SMART drive status SSH / Telnet login SSL tunnels SAMBA windows file sharing Scheduled commands Sendmail mail server Shoreline firewall Squid analysis report generator Squid proxy server Voicemail server WU-FTP server Idmapd server

Restart webmin:

service webmin restart

Configure Rpmforge Repo

rpm -Uhv http://packages.sw.be/rpmforge-release/rpmforge-release-0.3.6-1.el5.rf.i386.rpm

NOTE: If you are using a different architecture check on https://rpmrepo.org/RPMforge/Using for the correct rpm

Disable the repo (such that base packages not overwritten) edit /etc/yum.d/rpmforge.repo and set the following option:

enabled = 0

Install Extra Required Packages

Install clamav:

yum --enablerepo=rpmforge install clamav clamav-db clamav-milter clamd -y wget http://www.topdog-software.com/files/clamav-milter.patch patch /etc/init.d/clamav-milter < clamav-milter.patch chkconfig --del clamd freshclam

Install sanesecurity signatures:

wget http://www.sanesecurity.co.uk/clamav/update_sanesecurity.txt -O /usr/local/bin/update_sanesecurity.sh chmod +x /usr/local/bin/update_sanesecurity.sh ln -s /usr/local/bin/update_sanesecurity.sh /etc/cron.hourly/ /usr/local/bin/update_sanesecurity.sh

Install PHP eaccelerator:

yum --enablerepo=rpmforge install php-eaccelerator

Install newer spamassassin package from rpmforge:

yum --enablerepo=rpmforge upgrade spamassassin

Install spamass-milter:

yum --enablerepo=rpmforge install spamass-milter

Install perl modules required by spamassassin:

perl -MCPAN -e 'install Mail::SPF' perl -MCPAN -e 'install Mail::SPF::Query' perl -MCPAN -e 'install Net::Ident' perl -MCPAN -e 'install IP::Country::Fast' perl -MCPAN -e 'install Mail::DomainKeys' perl -MCPAN -e 'install Mail::DKIM'

Install fuzzyOCR:

yum --enablerepo=rpmforge install netpbm-progs ocrad gocr gifsicle giflib-utils giflib -y svn co https://svn.own-hero.net/fuzzyocr/trunk/devel/ cd devel/ perl -MCPAN -e 'install String::Approx' perl -MCPAN -e 'install Time::HiRes' perl -MCPAN -e 'install Log::Agent' cp -rv {FuzzyOcr.cf,FuzzyOcr.scansets,FuzzyOcr.preps,FuzzyOcr.pm,FuzzyOcr.words,FuzzyOcr/} /etc/mail/spamassassin chcon -R system_u:object_r:etc_mail_t /etc/mail/spamassassin/{FuzzyOcr.cf,FuzzyOcr.scansets,FuzzyOcr.preps,FuzzyOcr.pm,FuzzyOcr.words,FuzzyOcr/} wget http://www.gbnetwork.co.uk/mailscanner/FuzzyOcr.words -O /etc/mail/spamassassin/FuzzyOcr.words

Install Razor:

yum --enablerepo=rpmforge install razor-agents -y

Install roundcube:

yum install php-imap rpm -Uvh http://www.topdog-software.com/oss/roundcube/roundcube-0.1-rc2.noarch.rpm

Install imapproxy:

wget http://imapproxy.org/downloads/up-imapproxy-1.2.6.tar.gz rpmbuild -tb up-imapproxy-1.2.6.tar.gz rpm -Uvh /usr/src/redhat/RPMS/i386/up-imapproxy-1.2.6-1.i386.rpm

Activate services:

chkconfig --level 345 httpd on chkconfig --level 345 postfix on chkconfig --level 345 spamassassin on chkconfig --level 345 spamass-milter on chkconfig --level 345 clamav-milter on chkconfig --level 345 mysqld on chkconfig --level 345 named on chkconfig --level 345 vsftpd on chkconfig --level 345 dovecot on chkconfig --level 345 imapproxy on

Configuration

Postfix Setup

Introduction

We will be setting up postfix with the following features:

Virtual hosting UCE prevention Anti virus SMTP authentication TLS RBLs SPF Attack mitigation

The adding of accounts and domains with be configured through virtualmin although it can be done manually as well. The setup is designed to be resource friendly so should be able to run on machines that are not over spec'ed so enabling the resources to be put to better use. To make it resource friendly we are not using external databases to store virtual user information like most other how-to's do as well as using milters for spam and virus checking as opposed to running amavisd-new.

The Basics

To begin with we will configure the basics such as the hostname, mail origin, networks, hash maps spool directory. All these configuration options should be added to /etc/postfix/main.cf unless stated. Sample configuration files are available for download at the end of this page.

command_directory = /usr/sbin daemon_directory = /usr/libexec/postfix mydomain = example.com myorigin = $mydomain mynetworks = 127.0.0.0/8 alias_maps = hash:/etc/aliases alias_database = hash:/etc/aliases canonical_maps = hash:/etc/postfix/canonical sender_canonical_maps = hash:/etc/postfix/canonical recipient_canonical_maps = hash:/etc/postfix/canonical virtual_alias_maps = hash:/etc/postfix/virtual mail_spool_directory = /var/spool/mail

Maildir

We will use the much improved maildir format as opposed to the default mbox format:

home_mailbox = Maildir/

SASL

To perform SMTP authentication we will be using SASL, however we will not use the Cyrus SASL as that requires us to run the saslauthd daemon, we will instead use dovecot sasl since we will be running dovecot for IMAP and POP3 thus killing 2 birds with one stone.

smtpd_sasl_type = dovecot smtpd_sasl_path = private/auth smtpd_sasl_auth_enable = yes

TLS

We need TLS to ensure that the plain text passwords are not transmitted over the wire during SMTP authentication, servers that support TLS are also able to communicate with this server over a secured connection.

Instructions on creating your server certificate signed by cacert.org are can be found here.

Set TLS random source:

tls_random_source = dev:/dev/urandom

Enable server TLS:

smtpd_use_tls = yes smtpd_tls_key_file = /etc/pki/postfix/key.pem

smtpd_tls_cert_file = /etc/pki/postfix/server.pem smtpd_tls_CAfile = /etc/pki/postfix/root.crt smtpd_tls_loglevel = 1 smtpd_tls_received_header = yes smtpd_tls_session_cache_timeout = 3600s smtpd_tls_session_cache_database = btree:/var/spool/postfix/smtpd_tls_cache

Enable client TLS:

smtp_use_tls = yes smtp_tls_key_file = /etc/pki/postfix/key.pem smtp_tls_cert_file = /etc/pki/postfix/server.pem smtp_tls_CAfile = /etc/pki/postfix/root.crt smtp_tls_session_cache_database = btree:/var/spool/postfix/smtp_tls_cache smtp_tls_note_starttls_offer = yes

Spam Prevention

Require a valid EHLO / HELO:

smtpd_helo_required = yes

Prevent email address harvesting attacks:

disable_vrfy_command = yes

Change reject codes to permanent (by default postfix issues 4xx error codes which implies temporary failure we need 5xx for permanent errors):

unverified_recipient_reject_code = 550 unverified_sender_reject_code = 550 unknown_local_recipient_reject_code = 550

Setup sender address verification:

address_verify_map = btree:/var/spool/postfix/verify smtpd_sender_restrictions = hash:/etc/postfix/sender_access

Create /etc/postfix/sender_access and add:

#sample /etc/postfix/sender_access contains frequently spoofed domains aol.com reject_unverified_sender hotmail.com reject_unverified_sender yahoo.com reject_unverified_sender gmail.com reject_unverified_sender bigfoot.com reject_unverified_sender

Mitigate attacks from zombies and broken clients:

smtpd_error_sleep_time = 5s smtpd_soft_error_limit = 10 smtpd_hard_error_limit = 20

Only allow pipelining from authenticated clients:

smtpd_data_restrictions = reject_unauth_pipelining

Install postfix-policyd-spf-perl and enable SPF support:

wget http://www.openspf.org/blobs/postfix-policyd-spf-perl-2.005.tar.gz tar xzvf postfix-policyd-spf-perl-2.005.tar.gz cd postfix-policyd-spf-perl-2.005 cp postfix-policyd-spf-perl /etc/postfix/

Sample Configuration Files

main.cf master.cf canonical virtual

Dovecot Setup

Introduction

This will setup dovecot as our IMAP/POP3 server.

Basic Configuration

We will setup dovecot for IMAP and POP3 and disable SSL.

protocols = imap pop3 listen = * ssl_listen = * ssl_disable = yes

Maildir

We will use the maildir format as opposed to the default mbox format.

mail_location = maildir:~/Maildir

Authentication & SASL

Configure dovecot to use LOGIN and PLAIN as the authentication mechanisims as many MS clients are unable to use encrypted authentication mechanisms. We also setup the SASL socket to enable postfix to authenticate SMTP connections using dovecot.

auth default { mechanisms = plain login passdb pam { } userdb passwd { } socket listen { client { path = /var/spool/postfix/private/auth mode = 0660 user = postfix group = postfix

} } }

Client Issues

Some MS imap clients in the outlook family have issues with both thier IMAP and POP3 implementations so we need to accommodate them by setting up these work arounds:

protocol imap { imap_client_workarounds = outlook-idle delay-newmail } protocol pop3 { pop3_client_workarounds = outlook-no-nuls oe-ns-eoh }

Run IMAP Behind Proxy

The imap server is configured to run on port 10143 such that port 143 is handled by the imap proxy server that will improve performance for your webmail by caching connections to the imap server. The listen option under protocol sets this up.

protocol imap { imap_client_workarounds = outlook-idle delay-newmail listen = 127.0.0.1:10143 }

Sample files

dovecot.conf

Setup Imap Proxy

Introduction

imapproxy was written to compensate for webmail clients that are unable to maintain persistent connections to an IMAP server. Most webmail clients need to log in to an IMAP server for nearly every single transaction. This behaviour can cause tragic performance problems on the IMAP server. imapproxy tries to deal with this problem by leaving server connections open for a short time after a webmail client logs out. When the webmail client connects again, imapproxy will determine if there's a cached connection available and reuse it if possible. - according to the imapproxy website.

Configuration

Make the following changes in the file /etc/imapproxy.conf:

server_hostname 127.0.0.1 cache_size 3072 listen_port 143 server_port 10143 cache_expiration_time 900 proc_username nobody proc_groupname nobody stat_filename /var/run/pimpstats protocol_log_filename /var/log/imapproxy_protocol.log syslog_facility LOG_MAIL send_tcp_keepalives no enable_select_cache yes foreground_mode no force_tls no enable_admin_commands no

Sample Files

imapproxy.conf

Bind Setup

Introduction

Bind will be set up chrooted to improve security we will also use views to prevent abuse of the dns server.

Basic Configuration

The basic configuration disables by default, recursive queries and zone transfers. We also obscure the version of BIND we are running such that we are not hit by zero day vulnerabilities from script kiddies.

options { directory "/var/named"; pid-file "/var/run/named/named.pid"; listen-on { 127.0.0.1; 192.168.1.5; }; version "just guess"; allow-recursion { "localhost"; }; allow-transfer { "none"; }; };

Logging

The logging is customized to remove the annoying "lame-server" and update errors that appear in the logs:

logging { category update { null; }; category update-security { null; }; category lame-servers{ null; };

};

Chroot

Ensure that this is set in the file /etc/sysconfig/named (it's usually set by the bind-chroot package):

ROOTDIR=/var/named/chroot

Point Server

Let the machine use this server for dns resolution edit /etc/resolv.conf and prepend:

nameserver 127.0.0.1

Sample files

named.conf /etc/sysconfig/named

Vsftpd Setup

Introduction

We will use vsftpd as our ftp server. This has a better track record as opposed to the proftpd & wuftpd servers.

Basic Setting

Our basic setup disables anonymous users, and enables local system users to connect to the ftp server.

anonymous_enable=NO local_enable=YES write_enable=YES local_umask=022 anon_upload_enable=NO anon_mkdir_write_enable=NO dirmessage_enable=YES xferlog_enable=YES connect_from_port_20=YES xferlog_file=/var/log/vsftpd.log xferlog_std_format=YES ftpd_banner=Welcome to example.com server pam_service_name=vsftpd tcp_wrappers=YES

Chroot

All users will be chrooted to their home directories (except usernames in the /etc/vsftpd/chroot_list file) meaning the cannot break out and see other users files.

chroot_list_enable=YES chroot_local_user=YES chroot_list_file=/etc/vsftpd/chroot_list

Banned Users

Users added to the file /etc/vsftpd/user_list will not be allowed to login:

userlist_enable=YES

Sample Files

vsftpd.conf user_list chroot_list

Clamav Milter Setup

Edit /etc/sysconfig/clamav-milter:

CLAMAV_FLAGS=" --config-file=/etc/clamd.conf --force-scan --local --max-children=5 --sendmail-cf= --outgoing --quiet " SOCKET_ADDRESS="local:/var/clamav/clmilter.socket"

Patch the init file to fix socket permissions:

wget http://www.topdog-software.com/files/clamav-milter.patch patch /etc/init.d/clamav-milter < clamav-milter.patch

MySQL Setup

Basic Config

Listen only to the localhost, edit /etc/my.cnf under the mysqld section:

bind-address = 127.0.0.1

Set Root Password

Set the root password:

service mysqld start mysqladmin -u root password NEWPASSWORD

SpamAssassin Setup

Basic Config

required_hits 5 report_safe 0 rewrite_header Subject [SPAM]

Create MySQL Database

Create the database:

mysqladmin -p create bayes

Populate the database:

mysql -p bayes < /usr/share/doc/spamassassin-$(rpm --qf %{VERSION} -q spamassassin)/sql/bayes_mysql.sql

Create the user:

mysql -p mysql> GRANT ALL ON bayes.* TO bayes@localhost IDENTIFIED BY 'password';

Configure To Use DB

Edit the file /etc/mail/spamassassin/local.cf and add:

bayes_store_module Mail::SpamAssassin::BayesStore::MySQL bayes_sql_dsn DBI:mysql:bayes:localhost bayes_sql_override_username bayes bayes_sql_username bayes bayes_sql_password password

Configure FuzzyOCR

We will be storing the image hashes in a mysql database to improve on performance such that images that we have already scanned do not get scanned again as OCR is a resource intense activity.

Create MySQL Database

The sql script creates the database and tables and adds a user fuzzyocr with the password fuzzyocr:

mysql -p < /usr/local/src/devel/FuzzyOcr.mysql

Change the password:

mysqladmin -u fuzzyocr -p fuzzyocr password

Basic Settings

Edit /etc/mail/spamassassin/FuzzyOCR.cf and set the basic options:

focr_path_bin /usr/bin:/usr/local/bin focr_minimal_scanset 1 focr_autosort_scanset 1 focr_enable_image_hashing 3 focr_logfile /tmp/FuzzyOcr.log

Make FuzzyOCR Use The Database

Edit the file /etc/mail/spamassassin/FuzzyOcr.cf and add:

focr_mysql_db FuzzyOcr focr_mysql_hash Hash focr_mysql_safe Safe focr_mysql_user fuzzyocr focr_mysql_pass password focr_mysql_host localhost focr_mysql_port 3306 focr_mysql_socket /var/lib/mysql/mysql.sock

SARE Rule Updates

Import the GPG key used to sign the rules:

mkdir /etc/mail/spamassassin/sa-update-keys/ chmod 700 /etc/mail/spamassassin/sa-update-keys/ wget http://daryl.dostech.ca/sa-update/sare/GPG.KEY sa-update --import GPG.KEY

Create the channels file /etc/mail/spamassassin/sare-sa-update-channels.txt:

updates.spamassassin.org 72_sare_redirect_post3.0.0.cf.sare.sa-update.dostech.net 70_sare_evilnum0.cf.sare.sa-update.dostech.net 70_sare_bayes_poison_nxm.cf.sare.sa-update.dostech.net 70_sare_html0.cf.sare.sa-update.dostech.net 70_sare_html_eng.cf.sare.sa-update.dostech.net 70_sare_header0.cf.sare.sa-update.dostech.net 70_sare_header_eng.cf.sare.sa-update.dostech.net 70_sare_specific.cf.sare.sa-update.dostech.net

70_sare_adult.cf.sare.sa-update.dostech.net 72_sare_bml_post25x.cf.sare.sa-update.dostech.net 99_sare_fraud_post25x.cf.sare.sa-update.dostech.net 70_sare_spoof.cf.sare.sa-update.dostech.net 70_sare_random.cf.sare.sa-update.dostech.net 70_sare_oem.cf.sare.sa-update.dostech.net 70_sare_genlsubj0.cf.sare.sa-update.dostech.net 70_sare_genlsubj_eng.cf.sare.sa-update.dostech.net 70_sare_unsub.cf.sare.sa-update.dostech.net 70_sare_uri0.cf.sare.sa-update.dostech.net 70_sare_obfu0.cf.sare.sa-update.dostech.net 70_sare_stocks.cf.sare.sa-update.dostech.net

Create an update script /usr/local/bin/update-sa:

#!/bin/bash # # sa-update -D --channelfile /etc/mail/spamassassin/sare-sa-update-channels.txt --gpgkey 856AA88A &>/var/log/sa-updates.log

Make it executable and add to cron:

chmod +x /usr/local/bin/update-sa ln -s /usr/local/bin/update-sa /etc/cron.daily/ ln -s /usr/local/bin/update-sa /etc/cron.hourly/

Spamass-milter Setup

Basic Configuration

Edit /etc/sysconfig/spamass-milter:

SOCKET=/var/run/spamass.sock EXTRA_FLAGS="-m -r 8"

Patch

We need to patch the init file to fix the permissions of the socket created such that postfix is able to use the socket.

wget http://www.topdog-software.com/files/spamass-milter.patch patch /etc/rc.d/init.d/spamass-milter < spamass-milter.patch

Apache Setup

Disable Modules

We will disable some modules that we are not using thus freeing up memory and also improving security.

Edit /etc/httpd/conf/httpd.conf and comment out the modules as below.

#LoadModule ldap_module modules/mod_ldap.so #LoadModule authnz_ldap_module modules/mod_authnz_ldap.so #LoadModule dav_module modules/mod_dav.so #LoadModule status_module modules/mod_status.so #LoadModule dav_fs_module modules/mod_dav_fs.so #LoadModule proxy_module modules/mod_proxy.so #LoadModule proxy_balancer_module modules/mod_proxy_balancer.so #LoadModule proxy_ftp_module modules/mod_proxy_ftp.so #LoadModule proxy_http_module modules/mod_proxy_http.so #LoadModule proxy_connect_module modules/mod_proxy_connect.so #LoadModule cache_module modules/mod_cache.so #LoadModule disk_cache_module modules/mod_disk_cache.so #LoadModule file_cache_module modules/mod_file_cache.so #LoadModule mem_cache_module modules/mod_mem_cache.so

Edit /etc/httpd/conf.d/proxy_ajp.conf and comment out as below:

#LoadModule proxy_ajp_module modules/mod_proxy_ajp.so

Listen To One IP For HTTPS

Apache has to be configured to listed to one address for port 443 as webmin will be using the same port. Edit /etc/httpd/conf.d/ssl:

Listen 192,168.1.6:443

Enable Gzip Compression

We setup gzip compression via the mod_deflate module to improve web server performance and to cut down on bandwidth usage by compressing responses to the client.

SetOutputFilter DEFLATE BrowserMatch ^Mozilla/4 gzip-only-text/html BrowserMatch ^Mozilla/4\.0[678] no-gzip BrowserMatch \bMSIE !no-gzip !gzip-only-text/html SetEnvIfNoCase Request_URI \ \.(?:gif|jpe?g|png)$ no-gzip dont-vary Header append Vary User-Agent env=!dont-vary

Set up logging for the deflate module:

DeflateFilterNote deflate_ratio LogFormat "%v %h %l %u %t \"%r\" %>s %b mod_deflate: %{deflate_ratio}n pct." vhost_with_deflate_info CustomLog logs/deflate_access_log vhost_with_deflate_info

Increase PHP Max Memory

Edit the file /etc/php.ini and set the following:

memory_limit = 64M

Enable Virtual Hosting

NameVirtualHost *:80

Create Default Virtual Host

This needs to be the first virtual host, it will be the default on the server the equivalent of the server with out virtual hosting.

<VirtualHost *:80> Servername localhost.localdomain Serveradmin root@localhost.localdomain </Virtualhost>

Roundcube Webmail Setup

Create Database

Create the database and add the roundcube user.

mysqladmin -p create roundcube mysql -p mysql> GRANT ALL ON roundcube.* TO roundcube@localhost IDENTIFIED BY 'password';

Initialize the database:

mysql -u roundcube -p roundcube < /usr/share/doc/roundcube-0.1/SQL/mysql5.initial.sql

Basic Config

Configure database DSN in /var/www/roundcube/config/db.inc.php:

$rcmail_config['db_dsnw'] = 'mysql://roundcube:password@localhost/roundcube';

Configure roundcube in /var/www/roundcube/config/main.inc.php:

$rcmail_config['default_host'] = 'localhost'; $rcmail_config['default_port'] = 143; $rcmail_config['virtuser_file'] = '/etc/postfix/virtual'; $rcmail_config['smtp_server'] = 'localhost'; $rcmail_config['smtp_port'] = 25; $rcmail_config['smtp_helo_host'] = 'localhost';

Set Up Catch All Virtualhost

As we will be providing webmail for all domains that are created on the system we need to setup a catch all virtualhost that can display roundcube when ever a user accesses http://webmail.domainname. Edit /etc/httpd/conf/httpd.conf and append:

<VirtualHost *:80> ServerName webmail.example.com ServerAlias webmail.* DocumentRoot /var/www/roundcube <Directory /var/www/roundcube> Options -Indexes IncludesNOEXEC FollowSymLinks allow from all </Directory> </VirtualHost>

Firewall Setup

Introduction

This is a basic firewall it may not suit your needs, firewalling is an art so i recommend to read into it to improve on this basic one.

Basic Config

Add these rules in your configuration file /etc/sysconfig/iptables:

*raw :PREROUTING ACCEPT [0:0] :OUTPUT ACCEPT [0:0] COMMIT *nat :PREROUTING ACCEPT [0:0] :POSTROUTING ACCEPT [0:0] :OUTPUT ACCEPT [0:0] COMMIT *mangle :PREROUTING ACCEPT [0:0] :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] :POSTROUTING ACCEPT [0:0] COMMIT *filter :FORWARD DROP [0:0] :INPUT DROP [0:0] :OUTPUT DROP [0:0] -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT -A INPUT -p tcp -m tcp --dport 21 -j ACCEPT -A INPUT -p tcp -m multiport -j ACCEPT --dports 80,443,25,110,143,53 -A INPUT -p udp -m udp --dport 53 -j ACCEPT -A INPUT -p icmp -m icmp -m limit --icmp-type 8 --limit 5/min -j ACCEPT -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A OUTPUT -s 127.0.0.1 -j ACCEPT -A OUTPUT -s 192.168.1.5 -j ACCEPT -A OUTPUT -s 192.168.1.6 -j ACCEPT COMMIT

Activate Config

service iptables restart

Configure Virtualmin

Introduction

Virtualmin is a powerful and flexible hosting control panel that integrates with webmin. We will be using it to provide the virtual hosting functions such as creation of domains, accounts and maintaining configurations on the system.

Start Services

You need to start up services that are required to be able to configure virtualmin. Start the following services:

service named start service spamassassin start service spamass-milter start service clamav-milter start service postfix start service dovecot start service imapproxy start service httpd start

Initial Settings

MySQL

Webmin needs to be able to communicate with mysql since we have set a password for mysql we need to set that up in webmin, go to servers ? mysql and enter this information:

Configure Features

You need to enable the features and plugins that we want to use. On login this is the screen that you will see.

Enable the following features and save o Home directory o Administration user o Mail for domain

o BIND DNS domain o Apache website o Webalizer reporting o Log file rotation o Mysql database o Webmin user

Configure Server Templates

Server template are used to customize the services and to create packages for different hosting account types.

Apache Template

You can make changes to the way apache virtual hosts are created by editing this template, The defaults however will do for purposes of this howto.

Domain Owner Template

This template is used to configure various server limits such as number of mailboxes,aliases,databases,virtual servers and other options like bandwidth limits, admin abilities. For this howto we will use the default values.

Home Directory Template

This template allows you to set a skel directory to hold setting for new users for this howto we will use the defaults.

Administration User

This template lets you set the quota for the virtual server and the admin user for this howto we will use the default quota 1GB.

Mail For Domain Template

This template sets various mail related options, we will modify the email message sent on server creation to have the content below:

The following virtual server has been set up successfully : Domain name: ${DOM} Hosting server: ${HOSTNAME} ${IF-VIRT} Virtual IP address: ${IP} ${ENDIF-VIRT} Administration login: ${USER} Administration password: ${PASS} ${IF-WEBMIN} Administration URL: ${WEBMIN_PROTO}://www.${DOM}:${WEBMIN_PORT}/ ${ENDIF-WEBMIN} ${IF-WEB} Website: http://www.${DOM}/ ${IF-WEBALIZER} Webalizer log reporting: Enabled ${ELSE-WEBALIZER} Webalizer log reporting: Disabled ${ENDIF-WEBALIZER} ${ENDIF-WEB} ${IF-MAIL} Email domain: ${DOM} SMTP server: mail.${DOM} POP3 server: mail.${DOM} Webmail: webmail.${DOM} ${ENDIF-MAIL} ${IF-DNS} DNS domain: ${DOM} Nameserver: ${HOSTNAME} ${ENDIF-DNS} ${IF-MYSQL} MySQL database: ${DB} MySQL login: ${MYSQL_USER} MySQL password: ${PASS} ${ENDIF-MYSQL} ${IF-POSTGRES} PostgreSQL database: ${DB} PostgreSQL login: ${USER} PostgreSQL password: ${PASS} ${ENDIF-POSTGRES}

We will leave the other options as the defaults.

BIND DNS Domain Template

This template is used to customize the zones that will be created by virtualmin. The changes to be made are adding a spf record, add the following records to auto generated text box (replace ns1.home.topdog-software.com. with your slave server):

@ IN NS ns1.home.topdog-software.com. ;slave admin IN A 192.168.1.6 ;virtualmin webmail IN A 192.168.1.5 ;webmail

In the directives text box add the following with the IP address of your slave server such that the slave is allowed to do zone transfers.

allow-transfer { 192.168.1.2; };

MySQL Database Template

Contains options on creation of databases by virtualmin, for the howto we will use the defaults.

Webmin Login Template

Contains option on creation of new users by virtualmin, for the howto we will use the defaults.

Create Virtual Server

Finally we have a working virtual server system, lets create our first virtual server. Go to servers ? virtualmin virtual servers and click add new virtual server, owned by new user.

Fill in the require fields and click create.

Add a mail user to the domain. click on the domain name, then click edit mail and FTP users, then add user and fill in the information.

Testing

Postfix

Test SMTP

telnet 192.168.1.5 25 Connected to localhost. Escape character is '^]'. 220 tds mail cluster helo me 250 hosting1 mail from:address@yahoo.com 250 2.1.0 Ok rcpt: andrew@example.com 250 2.1.0 Ok DATA 354 End data with <CR><LF>.<CR><LF> From:address@yahoo.com To:andrew@example.com Subject:This is a test Hi This is a test . 250 2.0.0 Ok: queued as 4ACCC7C5A6

telnet 192.168.1.5 25 Trying 192.168.1.5... Connected to localhost. Escape character is '^]'. 220 tds mail cluster ehlo me 250-hosting1 250-PIPELINING 250-SIZE 10240000 250-ETRN 250-STARTTLS 250-ENHANCEDSTATUSCODES 250-8BITMIME 250 DSN

Test dkim

Send a mail to autorespond+dkim@dk.elandsys.com.

Test domainkeys

Send a mail to autorespond+dk@dk.elandsys.com.

Dovecot

Test POP3

telnet 192.168.1.5 110 +OK Dovecot ready. user andrew.example +OK pass password +OK Logged in. quit +OK Logging out.

Test IMAP

telnet 192.168.1.5 143 * OK Dovecot ready. 01 login andrew.example password 01 OK User logged in 01 list "" "*" * LIST (\HasNoChildren) "." "Trash" * LIST (\HasNoChildren) "." "Drafts" * LIST (\HasNoChildren) "." "Junk" * LIST (\HasNoChildren) "." "Sent" * LIST (\HasNoChildren) "." "INBOX" 01 OK List completed. 01 logout * BYE LOGOUT received 01 OK Completed

BIND

dig example.com @127.0.0.1

Clamav-milter

We are using the test virus from www.eicar.org.

telnet 192.168.1.5 25 Connected to localhost. Escape character is '^]'. 220 tds mail cluster helo me 250 hosting1 mail from:address@yahoo.com 250 2.1.0 Ok rcpt: andrew@example.com 250 2.1.0 Ok DATA 354 End data with <CR><LF>.<CR><LF> X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H* . 550 5.7.1 virus Eicar-Test-Signature detected by ClamAV - http://www.clamav.net quit 221 2.0.0 Bye

Take a lot at your /var/log/maillog you should see something like this:

73BC87C4E4: milter-reject: END-OF-MESSAGE from localhost[127.0.0.1]: 5.7.1 virus Eicar-Test-Signature detected by ClamAV - http://www.clamav.net; from=<address@yahoo.com> to=<andrew@example.com> proto=SMTP helo=<me>

Spamass-milter

We are using the test message from http://spamassassin.apache.org/gtube/.

telnet 192.168.1.5 25 Connected to localhost. Escape character is '^]'. 220 tds mail cluster helo me 250 hosting1 mail from:address@yahoo.com 250 2.1.0 Ok rcpt: andrew@example.com 250 2.1.0 Ok DATA 354 End data with <CR><LF>.<CR><LF> XJS*C4JDBQADN1.NSBN3*2IDNEN*GTUBE-STANDARD-ANTI-UBE-TEST-EMAIL*C.34X . 550 5.7.1 Blocked by SpamAssassin quit 221 2.0.0 Bye

You will see this in your log files:

spamd: result: Y 1002 - AWL,GTUBE,MISSING_SUBJECT,TVD_SPACE_RATIO,UNPARSEABLE_RELAY scantime=0.5,size=723,user=root,uid=99,required_score=5.0,