Virtualmin on a Debian Linode

See also my comments of installation of Virtualmin on a Centos linode... these are just the additional issues.

GD under PHP not installed by default

Wordpress and other PHP systems were reporting errors about "imagecreatefromjpeg not defined" ... that's a PHP built-in function... what gives? Somehow I didn't have the GD image manipulation module loaded into PHP. Here's how to do that.

# sudo apt-get install php5-gd
# /etc/init.d/apache2 restart

Locales not installed by default

(reported solved in Debian 5.0.2)

Apt-get was reporting huge batches of errors like:

perl: warning: Falling back to the standard locale ("C").
/usr/bin/mandb: can't set the locale; make sure $LC_* and $LANG are correct
manconv: can't set the locale; make sure $LC_* and $LANG are correct

The solution is to:

apt-get install locales
dpkg-reconfigure locales

and I added the locale: en_US.UTF-8 UTF-8

dpkg-reconfigure locales

Setting up Virtualmin on Centos with a Linode

Tags: apache centos clamd linode memory spamassassin tuning virtualmin

Once you know these few steps, setting up a LAMP (Linux/Apache/MySQL/Perl-PHP) server on a Linode (please use that link, as it includes my referral code) is insanely simple:

First, starting with a freshly provisioned CentOS install, ssh into the root account. First, update the base system --

yum update

`

I find it convenient to also install the console version of emacs:

yum install emacs-nox

`

Next, edit /etc/sysconfig/network and change the hostname. That file is read at boot, so you might also want to set the hostname for the current session:

hostname www.example.com

`

Download the install.sh script from http://www.virtualmin.com/download.html into /usr/src ... and then execute it:

cd /usr/src # wget http://software.virtualmin.com/gpl/scripts/install.sh

sh install.sh

`

Then login, as root, to your new virtualmin configuration at your linode's address: https://li99-999.members.linode.com:10000 where the 99-999 is replace with your linode's address (see the linode control panel).

Install problem: awstats

Ran into this error message after install, when clicking the "Check Your System" button --

The AWstats command /usr/share/awstats/wwwroot/cgi-bin/awstats.pl was not found on your system.

Complicated by the fact that "yum install awstats" said it was already installed. But where? "rpm -ql awstats" gives the answer... and then I just copied it as follows:

# mkdir -p /usr/share/awstats/wwwroot/cgi-bin
# cp -a /var/www/awstats/awstats.pl /usr/share/awstats/wwwroot/cgi-bin

Install problem: clamd (after update)

NOTE: After installing Virtualmin updates, I got an error:

ERROR: Command rejected by clamd (wrong clamd version?)

which I resolved with:

# /etc/rc.d/init.d/clamd-virtualmin restart

Default settings when you configure

Under System Settings / Server Templates and then Default Settings --

Mail for Domain / Mail alias mode for alias domains: * Copy aliases from target*. Catchall is the default! And you don't want that. See also "Postfix relaying" below.
Spam Filtering / Automatically delete old spam? Yes, if older than 7 days (or as you desire)
BIND DNS Domain / Hostname to your preferred world-visible hostname; SPF DNS disabled (until you configure each domain manually)

Upgrading PHP and MySQL

This is one place where Centos 5.3 lags behind the times. If you need PHP 5.2 or above, you will have to enable an alternate repository. As of this writing, the "Centos Testing" repository contains a pre-release version that does not include the mcrypt and memache modules -- a real problem. NOTE: Although I was able to upgrade a running server, I'd recommend doing this before loading any production domains. Follow the instructions at

http://www.virtualmin.com/documentation/system/bleed

Double-Check Postfix Relaying

Postfix was accepting email for anything@aliased-domain.com ... to solve this, open the aliased sub domain in Virtualmin, and under:

Server Configuration
  Email Settings

change:

Virtual server email-related settings
  Mail aliases mode

from Catchall forwarding to Copy aliases from target. You probably want to change this on the System Settings / Server Templates / Default Settings for Sub-Servers page as well. If you have already created several domains, you can adjust this all at once:

# virtualmin modify-mail --alias-copy --all-domains

NOTE: Is there a bug in Virtualmin 3.68.gpl? I had to manually:

# cd /etc/postfix
# postmap virtual
# postfix reload

to force that to refresh.

Tuning clamd

Rather than spend too much time tuning the memory, I simply killed clamd as it is a huge memory pig and leads to Out Of Memory webserver freezes.

Tuning Apache

With the default settings, Apache can veer out of control and eat all available memory. In /etc/httpd/conf/httpd.conf, change as follows in the section shown:

# prefork MPM
# StartServers: number of server processes to start
# MinSpareServers: minimum number of server processes which are kept spare
# MaxSpareServers: maximum number of server processes which are kept spare
# ServerLimit: maximum value for MaxClients for the lifetime of the server
# MaxClients: maximum number of server processes allowed to start
# MaxRequestsPerChild: maximum number of requests a server process serves
# was: MaxSpareServers 20 ServerLimit 256 MaxClients 256 MaxRequestsPerChild 400
0
<IfModule prefork.c>
StartServers       8
MinSpareServers    5
MaxSpareServers   10
ServerLimit      64
MaxClients       64
MaxRequestsPerChild  400
</IfModule>

Tuning Spamassassin

Dramatically reduce memory footprint by changing the number of threads that spamassassin will execute at once from 5 down to 1. In /etc/sysconfig/spamassassin (your location may vary) --

change:

SPAMDOPTIONS="-d -c -m<strong>5</strong> -H"

SPAMDOPTIONS="-d -c -m<strong>1</strong> -H"

-- William Lindley Automatically delete old spam?

Yes, if older than

daAutomatically delete old spam? No

Yes, if older than days