All the web infrastructure for http://sagemath.org and many related projects was knocked offline for a full day last week due to problems I had with my VMware server installation. I thus decided to learn the free open source competitor VirtualBox and see how it compares to VMware, and share some of my experiences with you. I'm comparing to VMware server running on a very high end Linux host (Sun X4450) to VirtualBox running on the same Linux host. I vastly prefer VirtualBox now, even though I was a diehard VMware user since 1998.
Ways VirtualBox is better then VMware Server:
- Both are free, but VirtualBox is free and open source (GPLv2!), whereas VMware server is "free" and closed source. It's possible to buy VMware server + more features for thousands of dollars / year, and I even considered it, but I *couldn't* figure out what I would get for my money from the confusing VMware site, despite coming back to it several times.
- VirtualBox is massively better at supporting OS X than VMware server: it is *impossible* (without running yet another virtual machine on my laptop!) to use the VMware server console to connect to remote virtual machines on OS X, since VMware uses a proprietary browser plugin that is only available for Windows and Linux. In contrast, VirtualBox uses a standard remote desktop protocol, so it is easy to connect to running VirtualBox consoles from any operating system using a range of different remote desktop clients.
- VMware server limits me to 2 cores and 8GB RAM per machine. VirtualBox has no such limitations. This is a *huge* factor for me, since the host server has 128GB RAM and 24 cores!
- If a virtual machines runs under VMware server and uses 4GB RAM (say), then VMware server will silently (and completely hidden) allocate around 4GB of disk space on the host filesystem. My host server has 128GB RAM, but only a 70GB hard disk. The net result is that I can't use the resources I have -- I have to run far less machines than I could, or give them less RAM. VirtualBox doesn't allocate any "secret" disk space at all.
- The web interface to VMware is extremely flaky and frustrating. It randomly fails to work with many of my web browsers, I often have to restart it, and it is clunky. There is no finished web interface to VirtualBox yet, but there is VBoxWeb, which is looks like it will be good when it is finished. Also, the command line interface to VirtualBox is amazing; I think it is vastly superior to VMware Server's. Also, there is a Python API for scripting VirtualBox machines. After spending a day learning VirtualBox, I wrote my own scripts to automatically start from the console all of my virtual machines in the background, and open remote desktop ports for each. I can easily see what is running using another little script, etc. With VMware server, even starting 20 machines was a tedious and painful exercise (probably if I paid it would be easier).
- The VirtualBox documentation is better. It doesn't "talk down" to me like I feel VMware's documentation does. It's clear and useful.
- VirtualBox is a single program that runs on Solaris, OS X, Linux and Windows. VMware, in contrast, is several different programs -- VMware player, VMware workstation, VMware server (and several versions of that). It can be really confusing and frustrating, with artificial limitations put on every program so as to extract your money.
- VMware is blatantly commercial (they went public a few years ago). Sun is also commercial, but they have a strong commitment to open source. Of course, I don't know what will happen with the Oracle acquisition.
- VMware completely stopped working on my main virtualization server, and despite upgrades, clean installs, etc., I absolutely could not get it to work again. I had to switch to running it on another computer temporarily.