A Technical Guy’s Blog

We use online forms to capture leads, from enquiries to successful sales order. Have you ever wonder what if the delivery mechanism fail and the leads are not delivered to you?

See, submission are sent to you by email. What if the email agent used by your online form is not working as expected? Will you be informed if the email was not sent successfully? As online forms taking care of all the important sales conversion, it is important for you to understand how it works.

Using built-in SMTP

If your website is hosted in a Linux server (you can tell if your website ends with .php, in most case), changes you are using Sendmail as the email agent of your online forms. Sendmail do trigger Error message if a message failed to deliver for some reasons. Anyway, the messages will go to the administrator of the server, not you - most of the time.

Another problem with build-in SMTP server is, when your web hosting and email hosting are in the same server. Your web form will most likely ’smart’ enough to route the submission of online forms to your mailbox. This will cause problem if you have some changes to your Mail Exchange pointing.

Using external SMTP

Just imagine the online form is now your email clients, such as Outlook Express. Everytime, an enquiry waiting to be delivered to you, your online form will connect to a specified SMTP, authorized as usual, and get the message delivered to you. You will have more control in this case, and your email hosting service provider will most likely provide you some status report for the uptime of your email server.

If your web hosting costs you around RM200-300 a year, chances are that it’s a shared basis. Perhaps I’m wrong. Dividing the yearly price to 12 months, I doubt how an average of RM20 monthly web hosting fee is enough to cover the cost of server hardware, bandwidth, co-location and even the unlimited mailbox account offered. That is barely enough for a McD set.

Where goes wrong then?

Forget about the page-long list of feature of those web hosting plan. Look for ‘Monthly data transfer’ and ‘No of website per server’. If you can find them, chances that you are in the right direction. Vaguely still, both offering tricky measurement which sounds to me like finding a virgin in a brothel.

It would be easier to put it this way

1) First offer allows you to stay in a hotel for X amount of days in a month. But didn’t tell you the fact that another 100 people are getting the same offer, and the hotel has just one room! - Monthly data transfer

2) Second offer limits to X amount of people who get the offer, but didn’t mention about the number of days each person will stay in this one-room hotel - No of website per server

What can I do?

Find out number of rooms. In this case, it is the dedicated bandwidth assigned to each website, not server. Remember, shared basis servers host not just your website. It makes huge differences here. A shared 1Mbps for 10 websites may be slower than single website with dedicated 256Kbps bandwidth.

Find out number of days one can stay in your second offer. In this case, check out the ‘Compute Cycles’ offered. It measures how much the processing time your application required in a server. 10,000 compute cycles are roughly equivalent to the monthly capacity of a server with a server with 1.2GHz modern processor. For example, a website with only static pages consumes less compute cycles than a website with shopping cart applications.

Is your website loading slow?

I see big corporate website paying as little as RM20 a month for their online infrastructure including email & web hosting (some with domain as well). I bet this amazing offer answer to the question above.

I always believe running a web hosting business is not easy. You can have a Plesk system to manage your web hosting customers, but you can’t easily filter out those customers who are abusing your web server, running malicious script that loop forever in your server…

Yet, price war makes business owner to believe that monthly web hosting fee should not be any expensive than buying a McD meal. You will be surprised that many online business owners are subscribing to cutting-throat web hosting package, while hoping their online business to grow as second Google.

Share with us your hosting experience

You get more than just signals! Well, this lovely website give you the ideas of who is hosted in he same server as yours. Before subscribing to a web hosting package, check this out. If the server has less website shared, it would be better. Having hundred over website (or even thousand, I came across it before), can be a rish!

Unless it was running on a load-balancing server, without single IP published. This is an exception!

List of Commands

Add New User

/usr/sbin/groupadd <groupname>
/usr/sbin/useradd <username> –g <groupname>
chown <username>.<groupname> /path/to/usernamefolder
chmod 755 /path/to/usernamefolder

Set User Password

passwd <yourusername>
<enter new password>
<enter again new password>

Check RPM Status

rpm –q <rpmname>
Eg. rpm –q imap

Extract a .tar File

tar –zxvf <filename>

Manual on a Specific Command

man <command>
Eg. man sendmail

End a Session

Ctrl + Z

./<command>

[root@kuittho /usr]# ./edquota
Specifies that the command edquota is located inside current folder [...]

Configure Virtual Server as Zope Server

Download current version of Python (2.3.5 or later) from http://www.python.org/download/.
wget –P /usr/src/ http://www.python.org/ftp/python/version/Python-version.tgz

Unpack and install current version of Python (2.3.5 or later). Using the instructions in README.txt.
tar –zxvf /usr/src/Python-version.tgz
cd /usr/src/Python-version
./configure
make
make install

Download current version of Zope (2.7.8 or later) from http://www.zope.org/Products.
wget –P /usr/src/ http://www.zope.org/Products/Zope/version/Zope-version-final.tgz

Download current version of Zope (2.7.8 or [...]

Configure Virtual Server as Mailman Server

Check if python is installed
rpm -qa | grep –I python

tar –zxvf mailman-version.tgz

Add Mailman group and user
groupadd mailman
useradd -c “GNU Mailman” -s /sbin/nologin -M -g mailman mailman

Create mailman folder in default prefix /usr/local/mailman
mkdir /usr/local/mailman
cd /usr/local/mailman/
chgrp mailman .
chmod a+rx,g+ws .

Install Mailman from /usr/src/mailman-version
./configure –with-mail-gid=mail –with-cgi-gid=apache
make
make install

Check and fix any permission error
Check file [...]

Configure Virtual Server as File Server

In the terminal, type startx to launch the Gnome interface

Enable run level 2, 3, 4 and 5 for Samba service using chkconfig.
chkconfig –level 2 smb on
chkconfig –level 3 smb on
chkconfig –level 4 smb on
chkconfig –level 5 smb on

Install samba-swat rpm that allows web-based administration of Samba service. Set swat in [...]

Backup

We use scp to transfer backup file in each server to a centralized backup server. We need to setup quick login with ssh Client Keys.

Generate a public/private key pair in the centralized backup server
ssh-keygen –t rsa
Just hit Enter when asked, this leave the passphrase empty.
This created two files, ~/.ssh/id_rsa and ~/.ssh/id_rsa.pub.

Copy id_rsa.pub to the server [...]

Monitoring

Nmap has the ability to test out open ports and discover what version of software is running.
nmap -O -p 1-65535 <host>

Offline Installation

The following steps need to be done for new network environment after offline installation.

/etc/resolv.conf, to add in more DNS server

/etc/sysconfig/network
NETWORKING=yes
HOSTNAME=<hostname>

/etc/hosts

127.0.0.1 localhost.localdomain localhost
<IP> <hostname> <hostname in short>

Eg:
203.115.228.142 it-lodge.ywso.com it-lodge

/etc/sysconfig/network-scripts/ifcfg-eth0

Remove BROADCAST=192.168.0.255 and NETWORK=192.168.0.0

/etc/sysconfig/network-scripts/ifcfg-eth1 (if any)

/etc/sysconfig/iptables

Set correct date on both system clock and hardware clock with the following command:
Set the system [...]

Default Setup

Run crontab –e to add the following setting:
MAILTO=root
0 6 * * 5 /sbin/shutdown -r now
0 2 1 * * /etc/rc.d/init.d/httpd stop; rm -f /etc/httpd/logs/*; /etc/rc.d/init.d/httpd start

Install info.php in /home/admin/web/php-bin
touch /home/admin/web/php-bin/info.php
vi /home/admin/web/php-bin/info.php
<? phpinfo(); ?>

Install phpMyAdmin in /home/admin/web/php-bin/phpmyadmin
wget –P /home/admin/web/php-bin http://<latest_phpmyadmin>
tar –zxvf /home/admin/web/php-bin/phpMyAdmin-latest.tar.gz
rm /home/admin/web/php-bin/phpMyAdmin-latest.tar.gz
mv phpMyAdmin-latest phpmyadmin
vi phpmyadmin/config.inc.php
$cfg['PmaAbsoluteUri'] = ‘http://<hostname>/php-bin/phpmyadmin/’;
$cfg['Servers'][$i]['auth_type'] = ‘http’;
$cfg['Servers'][$i]['user'] [...]

LogWatch

Edit Logwatch configuration file at /etc/log.d/logwatch.conf
Detail = High

Webalizer

Webalizer is a web server log file analysis program, which produces usage statistics in HTML format for viewing with a browser. The results are presented in both columnar and graphical format, which facilitates interpretation. Yearly, monthly, daily and hourly usage statistics are presented, along with the ability to display usage by site, URL, referrer, user [...]

CGIWrap

Assume we have main web root directory at /home/admin/web, and we would like to have CGIWrap transparently at the background. The cgi-bin folder is located inside web folder. Please change both the user and group in httpd.conf to apache.

tar -zxvf cgiwrap-version.tar.gz

./configure –with-cgi-dir=web/cgi-bin –with-httpd-user=apache –with-install-dir=/home/<user>/web/cgi-bin

make

make install

Update the httpd.conf file with
ScriptAlias /cgi-bin/ “/home/admin/web/cgi-bin/”
RewriteEngine On
RewriteMap lowercase int:tolower
RewriteRule ^/cgi-bin/(.*) [...]

PHP

PHP is a server-side, cross platform, HTML embedded scripting language. Learn more of PHP from http://www.php.net

You need php-mysql package to connect to a MySQL database. Download and install php-mysql-version.rpm. It is better to install a version of php-mysql that match with your native php and mysql that shipped together with your current Linux software.

Update [...]

MySQL Database Server

MySQL database server (http://www.mysql.com) is the world’s most popular open source database. With more than five million active installations, MySQL has quickly become the core of many high-volume, business-critical applications. MySQL has the capabilities to handle most corporate database application requirements with an architecture that is extremely fast and easy to use.

rpm -qa [...]

Apache HTTP Server

The Apache HTTP Server Project (http://httpd.apache.org) is an effort to develop and maintain an open-source HTTP server for modern operating systems including UNIX and Windows NT. The goal of this project is to provide a secure, efficient and extensible server that provides HTTP services in sync with the current HTTP standards.
Apache has been [...]

Sendmail

The sendmail program is installed by default. Type rpm -q sendmail to view sendmail version number.

By default, the date for /etc/mail/*.db is not correct and therefore you need to re-make the *.db file before you can start sendmail properly.
makemap hash /etc/mail/access < /etc/mail/access
makemap hash /etc/mail/virtusertable < /etc/mail/virtusertable
makemap hash /etc/mail/domaintable < /etc/mail/domaintable
makemap hash /etc/mail/mailertable < [...]

FTP Server

File Transfer Protocol is a way of transferring files over the Internet from one computer to another. You can connect to a FTP server, browse directories and transfer files. Red Hat Linux comes with different or updated version of FTP daemon with each release. Newer versions of Red Hat no longer support the wu-ftpd, [...]