Virtual development environment: Part II

  My previous post describes some alternatives of using virtualization. In this post I'll dig deeper into details of using virtual machines.

  Virtualization in software development process

   Windows host runs several virtual guests with Ubuntu. Virtual guests run as services. One of guests , let say Project 1, is configured to start 1-2 minutes later after Window start. So I have it always running and available at any time. Other guest machines which I don't use are turned off to save memory but ready to be started at any time. Guest machines have a static IP address; run SSH server, Samba server, MySQL server and Apache Tomcat with my web application. Have a look at the schema below for more clear picture of my configuration.

My web application for Project 1 is always available for HTTP access, as well as I can connect to it with remote debugger at any time. All files of the web application are shared to windows host with samba server.

 Virtual Network

  VMWare provides several ways to setup virtual network. I've choose one based on NAT. It hides your virtual machines from outside world behind the virtual NAT. However you can setup port forwarding to open your web application for outer world.

   I won't tell in this article about network setup process and static IP address configuration on the guest machine. There are a lot of resources on these topics. And if you are not familiar with Linux yet it would be cruel from my side to steal a wonderful trip over Linux tutorials, blogs, and first steps in command line by replacing exciting discoveries with a several predefined instructions ;).

  SSH, Putty and Samba

   Setting up an SSH Server on your guest is like opening a door to your development environment and to the Linux world.

   There are two nice tools for Windows OS: Putty and WinSCP, They allow you to connect to the guest by SSH protocol. With Putty you can run any command on guest, and with WinSCP you can navigate guest's machine file system, and transfer files.

  While WinSCP gives you a lot of power working on Linux, it has some issues. One example is that WinSCP always copy remote file to local temp folder before opening it. As a result it's impossible to use TortoiseSVN over WinSCP. If you feel inconveniences using WinSCP then try Samba.

  Samba opens Linux file system for Windows networks. When you'll additionally map this Linux shared folder as network drive you would have a seamless access to you virtual machine and will be able to use your favorite Windows tools for work with Linux files.

   Issues or "A cat in gloves catches no mice"

  One of the most interest issues I had with VMWare was so called "95% issue". A problem starting a virtual machine because it's hangs at 95 %. When I have read all 10 pages of VMware support forum, seeing lots of requests for help with a common answer from VMWare: "Your platform is not supported" My first intention was to stop using VMWare and switch to Sun's VirtualBox. Many people said that the issue was resolved with disk drivers. I was experimenting with them but with no luck. And only when I start recollecting all changes I made to computer recently, I come to solution. It was a WideCap tool conflicting with VMWare Server. After WideCap's uninstallation "95% issue" was resolved.

  Also I had an issue in using TortoiseSVN on drives shared with Samba, however it's resolving by security settings in Samba configuration.

Virtual development environment: Part I

   In the first post I'll share my experience of using virtualization platforms in software development process.

    Why to use virtualization?

   I've started to work with several open source and custom projects at the same time. This forced me to think about optimizing my computer for more comfortable and fast work. And especially to get rid of the mess that I had on my local MySQL server: It had around 30 database schemas. And it was difficult to find one of them that I need for the project. Below are main issues that I was solving:

• Work with several project simultaneously.
• Explore multiple open source projects and compare different versions. I'm trying to keep track of new features that appear in every version of Pentaho BI Server, Jasper Server and BIRT.
  
• Keep separate databases for every project. It helps to get rid of multiple schemas mess on the same database server.
• Learning other operation systems, testing software in different envieronments.

   How to use virtualization?

   Initially I thought about virtual development environment as a separate virtual machine for every project. With a standard set of tools installed like: SVN, Java, Eclipse, Tomcat. But after trying to work with virualization platforms I have come to decision that it's better to virtualize only server part without GUI. 

   Now I open all GUI tools on my host machine. And virtual machines play the role of GUI-less servers. So typical virtual machine is running Linux, MySql and a Tomcat with web application.

  One reason is that you will tend to move all programs like browser and mail client either to the guest machine or to the host. Because it's not convenient to switch often back and forth for copy-pasting. It's easier to use a single machine where you have a Browser, Mail Client, Instant Messangers and IDE.

   Another reason is that almost all virtualization platforms don't allow to use graphics-accelerator card on guest machine. And when you run your favorite IDE on machine without graphics-accelerator it looks quite poor. And most probably you will not like working with it. Fonts are less clear and everything other looks less attractive. 

   Which virtual platform to choose?

   When choosing virtualization platform I have considered following options:

• VMware(Player, Server, Worstation, ESXi)
• VirtualPC
• VirtualBox
• Xen

  I've chosen VMware Server. Because it's free and widespread. One thing I like most about VMware Server is that it's running as a windows service, and you never see it neither on taskbar nor in system tray. My guest machines is configured to run after Windows is started. So they never catch my eye, however are always available via virtual network.

    Xen and VMware ESXi are more complicated to setup and use. And also I don't sure if they will help with graphics-accelerator issue. 

   The results. 

    Here is a final configuration that I use:

    Host machine: 

• OS: Windows Vista Home Premium 64-bit. Windows was preinstalled on my notebook and I'm not yet ready to change it for Linux.
• Software:  VMware Server 2.0.2
• RAM Total: 4 Gb  
• RAM used by Windows Vista: 2Gb. But I need to admit that Windows releases some of allocated memory when other applications require. Up to 500Mb I suppose.

   Guest machine:

• OS: Ubuntu Server 9.10 32-bit.
• Software: Java, SSH server, MySQL, Glassfish, Pentaho
• RAM used by Ubuntu Server: less then 50 Mb.
• RAM total used when Glassfish is in debug mode: up to 1 Gb - 1.2 Gb.
• VMI support.

   Now I use only one always-running guest machine. But VMware Server is smart enough to allocate only as much RAM on host machine as guest's Ubuntu actually use. As a result I'm able to run 2-3 virtual machines on my host. Some of then with GUI. Ubuntu Desktop use about 150Mb.

   I have found my virtual development environment worth the time that I spend on it. However I still need to prove and check the advantages, because I'm working in this environment for only two month.

   In the next post I plan to share the issues and their solutions that I found while setting up virtual machines.