It has been almost 10 months since I started running Gentoo inside VMWare on my Windows desktop. It made coding at work (mostly application server related) much more bearable. I have since upgraded to VMWare Server, keeping my Gentoo installation in sync and the uptime of my Gentoo VM usually out-lives the uptime of my Windows host, if I remember to pause it before I reboot Windows due to various updates. I am pretty happy.
Then last month I decided to make some change to my Linux partition. First of all, I have decided to ditch ReiserFS for XFS as it has lower CPU utilisation. It’s pretty much a small single-user installation so I don’t need the speed I can get from ReiserFS, and since it runs on my notebook I want save battery when I am away from the mains.
I would like to pre-allocate the entire disk image. After a while the vmdk file gets a bit fragmented on NTFS and that really kills the performance. So I decided to just allocate the lot when I change the file system type at the same time.
Also VMWare Server recommended to use SCSI instead of IDE virtual drives. Well, the underlying physical drive is still that slow 4,200RPM 2.5inch notebook drive, but I can imaging that there’s more flexibility in emulating a SCSI bus than an IDE equivalent.
Now talking about changing hard drives, I can imagine how much work it is require to do on a physical server. Backing up the files, shutting down, installing the new drive into the physical server, rebooting, re-partitioning the drive, copying files over, doing the power cycle again to take the old drive out, etc. This kind of thing is almost too trivial on VMWare.
- Press that Red Button to shutdown your VM.
- Attach a newly created virtual SCSI disk.
- Attach a virtual CD-ROM drive that points to my rescue disc ISO.
- Power up VM, and boot into rescue disc.
- Mount both drives.
(cd /mnt/hda1; tar cf - .) | (cd /mnt/sda1; tar xvpf -)- Edit
/mnt/sda1/etc/fstaband/mnt/sda1/etc/lilo.conf. Runlilo -r /mnt/sda1. - Unmount both drives, and shutdown the VM again.
- Detach the old IDE drive. Detach CD-ROM as well as I probably don’t need it again.
- Boot up my VM — and all my files are now on this new “hard drive”!
And best of all, you can do all the above without a screw driver. Don’t I love VMWare?
I have found some interesting VMWare images at VirtualAppliances.net recently. They are tiny Linux images that can run on Xen or VMWare, and each image provides a single functionality. For example, you can grab a VM with PostgreSQL pre-installed at only 14Mb download.
Maybe that’s what the future appliances is. Instead of buying small gadgets that do well on one thing, you buy a beefy server, and then drop in many small “virtual gadgets”. Need an extra MySQL server? Just deploy another one using VMWare. Need a Firebird server? No problem. Too much load? Real-time migration of virtual appliances to another beefy server with minimum downtime.
There’s plenty of market on virtualization technology, and there’s plenty of market on those gadgets that utilise virtualization.
Hi. I found your site since I was implementing a gravatar cache myself and thought to check if anybody else had already done it! Then I noticed that you also have seen the joys of VMWare. I only just started migrating my physical servers to VMWare.
The move is slightly more painful since it involves an OS upgrade as well as PHP upgrade and re-write of some of the software. But the power and flexibility that virtual hardware gives you is amazing.
I love VMWare too. I use it for slightly more modest purposes including testing betas I’m not sure won’t mess up my OS, checking downloads for malware without installing on my machine, and solving OS capatibility with hardware. I’m a hardcore gamer on my main machine and have an Athlon 64 FX-62 mated with an ATI Radeon x1950PRO XGE graphics card. I first felt the pain of this when I tried a Kubuntu dual boot on the machine only to find out-my card is not supported by the open source community and ATI does not make a driver suitable for this distro! Stick Kubuntu in VMware, install the tools, get decent performance out of the unsupported hardware. I have been doing the same thing for old Windows games for as long as I can remember. Some hate every DOS style emulator but with VMWare, not an issue. I only wish for decent OpenGL support and good DirectX 8+ support wouldn’t hurt. Solves hardware compatibility issues like a treat. If you need an app on a different platform or one that is too old for your hardware and OS, give it a try! I use Workstation 6 beta currently.
This article was quite useful and informative. Thanks.
I could not find a reason why VMWARE recommends SCSI over IDE.
Is it because of SCSI’s inherent advantages over IDE?
Got the answer at http://www.vmware.com/support/pubs/server_pubs.html (VMware Server Administration Guide)
It says:
The various disk options (SCSI versus IDE) and types (virtual or physical) affect performance in a number of ways.
Overall, SCSCI disks are faster than IDE disks that uses direct memory access (DMA) However, in certain situations, such as single threaded disk access, an IDE disk that uses DMA is as fast as a SCSI disk. Inside a virtual machine, SCSI disks and IDE disks that use direct memory access (DMA) have approximately the same performance. If supported, VMware recommends that you enable DMA in SCSI disks. IDE disks can be very slow in a guest operating system that is not set to use DMA.