Sun VirtualBox is one of the hottest virtualization products around. Although I work with a performance group at Sun Microsystems, I have not been involved with programming or performance aspects of VirtualBox, therefore all my comments here are as an outsider to VirtualBox.
My experience of using VirtualBox has been simply great. I did have some hiccups getting everything working together, so this blogpost is intended to be a comprehensive summary of all that I had to scourge around the web to get things working.
I required virtualized operating systems (OSs) for my home desktop machine for some key requirements: My host OS is the latest Fedora. I host two websites at home: KnowMyDestination.com- A vertical search engine for travel; and AidsResearcher.org-a blog that my wife maintains. Hosting at home works well for websites which are young and have low volumes of traffic since you save on hosting fees. If you have a DSL or cable connection which gives you a dynamic IP, you may use dynamic DNS from zoneedit. But hosting at home also means that you would want your machine running 24x7. And so if you need any other OS for any other reason; you do need a virtualization tool. VirtualBox is free, and opensource, and this greatly helps. I needed the following guest OSs:
(i)Windows 7 Beta: I needed a Windows installation to try the latest OS from Microsoft and also for software such as Sopcast and iTunes.
(ii)Fedora 10: I needed another Fedora 10 so that I could run a VPN out of it without disrupting my Webserver. Virtualization really helps in this particular requirement.
(iii)Solaris Nevada release: I keep trying the latest unsupported release of Solaris Nevada available here which I work with Solaris OS code as my daily job.
Here is what I had to do to get everything working together. The most tricky part is to have a great display resolution in the guest OS, so please pay attention to them.
1) Installing Virtual Box on Fedora 10: For some reason the latest VirtualBox release 2.2.2 gave problems starting up on my Fedora 10. So I went back to 2.2.0 and thereafter thais was very smooth. Here are the steps which are documented in greater detail over here.
Get the kernel development packages:
yum install kernel-devel make automake autoconf gcc
Get the latest VirtualBox rpm and install it. Here is an example:
rpm -ivh VirtualBox-2.2.0_45846_fedora9-1.x86_64.rpm
Add users who can use virtualbox:
usermod -G vboxusers -a
VirtualBox, or open from the GUI.
2) Installing Windows 7 Beta Guest OS: Installing a guest OS on Virtual Box is pretty simple. One of the things I did not realize at first is the utility of the VirtualBox Media manager. There is no need to burn the iso image of the OS on a DVD, you can use the Media Manager to upload the iso image. When you start a new instance, Virtual Box requests the OS that is to be installed. The other information that VirtualBox needs is the amount of memory you would like to allocate for the guest OS, the amount of video memory, and a hard disk image where the guest OS will be installed. Most of these pop up with default values that Virtual Box recommends.
The installation went on very smoothly and once it completed, Windows came up just fine. The next step is to install the guest additions. This helps in a number of things - It helps in seamless integration of the mouse with the guest OS, and also in improving the display resolution. Once this was done, Windows booted up fine minus networking. I had to manually put in the DNS IP address as the IP address of my wireless router, and then the networking ran great.
I have observed that Windows Beta 7 requires at least 1 GB RAM to perform sanely, anything else would make the performance remarkably slow.
3) Installing Fedora 10 Guest OS : In a way installing guest OSs is almost similar. With Fedora 10, I didn't have to do any hanky-panky for networking. The display came up with 800x600 resolution. Interestingly the xorg.conf file was missing. I generated a xorg.conf file, manually edited it to match the settings in my Fedora 10 host OS xorg.conf, and then the resolution was excellent. Installing the guest additions was more tricky. When I ran the script, it complained about missing header files. The solution is to run "yum install kernel kernel-devel" so that all the kernel headers are installed. The script ran fine after this.
I installed vpnc and now I can connect to my work via vpn and also have the server running on the host OS at the same time. For some reason, my work DNS was not working on the guest OS although it worked easily on the host OS. I couldn't resolve this, but a easy solution was to manually add all the IP addresses I connect to, to the /etc/hosts file.
4) Installing Solaris Nevada : This by far was the easiest. The display came up in 1200\*1080, with networking going, so I didn't have much reason to play around with either of them.
On the whole, I have found the performance of guest OSs on VirtualBox extremely satisfactory. I worked on Word and Powerpoint presentations on Windows and the difference is barely noticable. There is a small difference in latency for Internet browsing, but nothing much to bother me.
I think what is important for VirtualBox though is having a lot of RAM on your machine. My machine has 2 GB RAM, and that was sufficient only for running the host OS with 1 GB RAM, and running one of the guest OSs with 1 GB RAM. Running more than one guest OSs with lesser memory inevitably had performance implications. For me this was not a limitation since I am not planning to work on multiple OSs at the same time.
What I feel is missing
1)I would love to have the drag-and-drop copy feature so that I can just cut and paste files from one OS to the other. I dont think VirtualBox supports this feature yet, and I am told from Internet postings that VMware Fusion does, so this will definitely be a great feature to have. As of now I am moving files around using scp which I find a pain, given that everything is in the same machine. Similarly there is no way I can copy a link from a browser in the host OS to a browser in the guest OS if I needed to.
2)Sound support: I still couldn't get sound working in any of my guest OSs, I plan to post an update when I get it up.
On the whole I am a very satisfied customer of VirtualBox and I hope they keep the good work up.