(1) Unlimited bandwidth is actually limited to the type of connection you have. On a 10baseT port, if you sustained 10 mbps for 30 days you would move 3200 GB’s of data. Shared hosts will probably limit you to a much lower port speed.
Unlimited disk space has it’s own limitations. Most hosts won’t let you store files which have nothing to do with your sites, like backup files, your private photos, etc.
Your CPU access is limited, speed and processes CPU usage and time is also limited. For example, Dreamhost sometimes doesn’t let me zip some larger directories because the zip process use too much CPU.
(2) My recommendation is www.dmehosting.com I have tried agnihost.com (which seems to be a virpus.com reseller) and burst.net before.
(3) I have been a Dreamhost client for 3 years. It stands out by allowing ssh access and python/django + ruby/rails support along with Php and Mysql.

Good to know when buying a VPS

• Xen virtualization is better than OpenVz
• test the server’s IP from the area where you get the most traffic on your sites
• get as much RAM as your budget allows
• 10Mbps unmetered or 3200GB bandwidth? Choose the 3200GB package if it’s on a 100baseT port. If it’s a 10baseT port either way, 10Mbps allows a maximum of 3200GB transfered in a month.
• search for special offers on forums, www.webhostingtalk.com is very good
• there are free alternatives to control panels like CPanel and Plesk. I am using webmin.com
• find some reviews on the service/company you are interested in. Stay away from those who generally made a bad impression to users.
• don’t go with the cheapest VPS, i learned that from experience A well established company will offer higher uptime, better support, more services.
• i like HyperVM better than SolusVM
• see if you can find out details about the CPU power offered with the package, unamanged VPS sellers usually advertise only ‘equally shared CPU’
  My first VPS had an AMD Opteron 270 which gave low benchmark scores. Currently, dmehosting is offering me i7 CPU 920 @ 2.67GHz, 4 cores
• 32 bit operating system consumes less memory than the 64 bit equivalent.

My setup

• I went with dmehosting.com after trying a virpus.com reseller and burst.net
• my hardware setup is similar to VPS 3, with the few customizations.
• the operating systems selection is large, I went with Ubuntu Lucid 10.04 32 bit because I use Ubuntu for both my desktop and laptop computer, 32 bit consumes less memory and Ubuntu Lucid is Long Term Support (LTS)
• webmin.com control panel, allows you to control most aspects of the VPS (apache, mysql, postfix, logs, etc)
• http://webmin.com/virtualmin.html for managing the domains and users
• http://www.configserver.com/cp/csf.html was my chosen firewall because of the integration with webmin and easy to use interface
• zend server community edition (Php 5.2) because some of my sites don’t work with Php 5.3 (which comes default with Ubuntu Lucid 10.04)
• server hardening operations.
  Find good server hardening here:
  http://delicious.com/search?p=server%20hardening&u=&chk=&context=main&fr=del_icio_us&lc=0
  http://delicious.com/florentin/hardening

Why dmehosting worked fine for me

• affordable prices
• use their own DNS servers
• choose from several server locations
• great CPU power, uptime, connection speed for the price you pay
• good customer support so far (only used twice, other people complain about the support)
• hardware configuration flexibility
• good presence on the webhostingtalk forum

Cheap unmanaged VPS services

• http://www.dmehosting.com/budget-linux-vps.php – I am happy customer there
• https://www.burst.net/linvps.shtml
• http://www.webhostingtalk.com/showthread.php?t=956901
• http://www.webhostingtalk.com/showthread.php?t=956764
• http://hostlatch.net/vps.html
• https://secure.hazenet.co.uk/cart.php
• https://www.2host.com/support/cart.php
• http://www.webhostingtalk.com/showthread.php?t=958605
• http://www.neutrino.us/en-us/services/vserver/default.aspx

Find the latest VPS offers

• http://www.webhostingtalk.com/forumdisplay.php?f=104
• http://www.lowendbox.com

Find VPS benchmark scores

• http://www.dmehosting.com/forums/showthread.php?172-Post-your-VPS-Benchmark
• http://www.webhostingtalk.com/showthread.php?t=924581

You can think of Zend Server as a bundle of software and Php modules.
For Linux, ZSCE has it’s own php-*-zend-server packages which replace the ones offered by the host Os, usually php5-*
ZSCE automatically installs lighttpd-zend-server used for the web-based administration.

Why to use Zend Server CE

• Easy to start with specially useful for Php newcomers
• Production-ready, integrated PHP stack for non-critical applications
• PHP bytecode caching (Zend Optimizer+) – increases performance with no application changes
• Data caching – a set of functions that allow developers to cache data in shared memory or to disk )
• Zend Debugger available out of the box but possible to disable it and install Xdebug
• Available on Windows, Linux and Mac
• All in one install taking care of all the dependencies and needed libraries
• Integrated administration console for setting up Apache and Php configurations
• Free (the CE version) and supported by Zend which takes care of bug fixes and future improvements
• Easy way to install Php 5.2 on Ubuntu Lucid or other distros which offer Php 5.3 by default
• Easy to uninstall with no traces left on the system
• Ability to install both Php 5.2 and Php 5.3 on the same system as described here http://ireallylikesushi.com/blog/2009/12/21/installing-both-zend-server-ce-php-5-2-php-5-3-on-snow-leopard/

Sources

http://www.zend.com/en/products/server-ce/

http://devzone.zend.com/article/4295

Installation (Ubuntu Lucid 10.04)

echo deb http://repos.zend.com/zend-server/deb server non-free > /etc/apt/sources.list.d/zend.list
wget http://repos.zend.com/deb/zend.key -O- | sudo apt-key add -
apt-get update
apt-get install zend-server-ce-php-5.2 # for Php 5.2
apt-get install zend-server-ce-php-5.3 # for Php 5.3

Please find the official installation details here:

http://files-source.zend.com/help/Zend-Server-Community-Edition/zend-server-community-edition.htm#deb_installation.htm

Installing Xdebug on Zend Server (an alternative to Zend Debug)

Option 1 (recommended)
# get archive, configure and compile it. First check the latest version on xdebug.org
wget http://www.xdebug.org/files/xdebug-2.1.0.tgz # replace it with the latest version
tar -xzf xdebug-2.1.0.tgz
cd xdebug-2.1.0/
/usr/local/zend/bin/phpize
./configure --enable-xdebug --with-php-config=/usr/local/zend/bin/php-config
make

# move the xdebug.so somewhere on the server
cp modules/xdebug.so /work/xdebug/xdebug.so
# edit zend-server's php.ini to enable xdebug
sudo gedit /usr/local/zend/etc/php.ini
# add to the end of the file
zend_extension=/work/xdebug/xdebug.so


# optionally, add some xdebug directives to that php.ini
[xdebug]
xdebug.profiler_output_dir = /tmp
xdebug.profiler_enable_trigger = 1
xdebug.remote_enable=1
xdebug.remote_host=localhost
xdebug.remote_port=9000
xdebug.remote_handler=dbgp
xdebug.var_display_max_data=10000
xdebug.var_display_max_depth=20


Option 2

ZSCE comes with a package named php-5.2-xdebug-zend-server. At this moment, the Xdebug version offered by ZSCE is older (2.0.4) than the official one (2.1.0)

# install xdebug.so in /usr/local/zend/lib/php_extensions/
apt-get install php-5.2-xdebug-zend-server
# Add the following line to /usr/local/zend/etc/php.ini
zend_extension=/usr/local/zend/lib/php_extensions/xdebug.so
# You may also add the xdebug directives described in Option 1.


Controlling Zend Server

# show all commands
sudo /usr/local/zend/bin/zendctl.sh -h

# restart zend server, including apache server and lighttpd server
sudo /usr/local/zend/bin/zendctl.sh restart

The end

# My bookmarks regarding Zend Server

http://delicious.com/florentin/zend-server

# Other bookmarks

http://delicious.com/search?p=zend%20server&u=&chk=&context=main&fr=del_icio_us&lc=0