Virtualization for the new user

[Infin8Cyn]

[quote="edge";p="720561"]Also, for the Mac users, there is Parallels Desktop. It's fast and easy to use.[/quote]

Now, I don't do much virtualization. I've used it a good bit for testing new driverpacks, WindowsXP Cd's, Win32 ASM Debugging, and a slew of other things.

Through trying VMWare, VPC, Parallels, QEMU and another or two, I can't agree that Parallels is fast. The last I tested it, it was actually the slowest of the bunch.

/me throws his $0.02 into the pot.

[Martin Blank]

[quote="LQDMTL";p="720550"]We pretty much LIVE on virtualization here at work. Almost our entire server farm is virtual, running on a handful of huge, beefy machines and a massive SAN system. Only a few aren't virtual, and they're scheduled to be virtualized later this year. And 1/3 of the company uses virtual machines for development, testing, etc.[/quote]
There are several reasons to not virtualize a server:

1. Exchange
2. Certain busy SQL servers, even if the database itself is kept on the SAN
3. Enterprise-scale monitoring systems, which can easily maintain a stable 60% CPU utilization on even moderate boxes
4. Anything that is related to your core security, such as firewalls and IDS

The first three should be kept off of VM servers for resource purposes, and the fourth so that a flaw in your host OS doesn't result in your security architecture getting owned.

Two interesting coming developments in virtualization:

1. Introduction of virtualization in the 2.6.20 Linux kernel. Not as good as dedicated virtualization products, but a lot better than the emulator products out there, it has the potential to start a major shift in how home computing is handled.

2. I/O virtualization is due out in the next year or so from both Intel and AMD. This will allow true and proper system virtualization, where the same system will run Windows and Linux (and Mac, with the right setup) side-by-side, with (possibly nearly) full access to every resource from sound to video to NIC, sharing the full capabilities of both. This may necessitate a lot of new hardware -- sound cards are notoriously finicky about how they handle multiple sources -- and probably all or mostly all of it will be on PCIe, but this will be most excellent in the long run, as a single moderate computer could handle an entire family's independent OSes.

[Deacon]

[quote="Martin Blank";p="720792"]There are several reasons to not virtualize a server:

1. Exchange
2. Certain busy SQL servers, even if the database itself is kept on the SAN
3. Enterprise-scale monitoring systems, which can easily maintain a stable 60% CPU utilization on even moderate boxes
4. Anything that is related to your core security, such as firewalls and IDS

The first three should be kept off of VM servers for resource purposes, and the fourth so that a flaw in your host OS doesn't result in your security architecture getting owned.[/quote]
Now hold on just a minute. "Exchange" is not a reason to abandon virtualization. You may recommend that, due to potentially high resource usage of systems running SQL or Exchange at an enterprise level, certain applications are best left to dedicated systems, but to say that those are all knocks against virtualization in general seems pretty extreme and odd. Neither firewalls nor IDS should be software programs regardless, but dedicated appliances, which makes me wonder where the in the world #4 came from.

Wait...the only thing I can think is that there must've been some miscommunication and that when talking about all the "reasons to not virtualize a server" you're really saying something more like "here are some exceptions where virtualizion may not be a good idea..." If so, that would make more sense to me, but I didn't read it that way the first time(s) through...

[Martin Blank]

You were correct in your second paragraph. Exchange, in our experience, runs very poorly in a virtualized environment, and this includes servers that cover as few as 100 users, and it gets worse from there.

My workplace now has something on the order of 200 virtualized servers, and within 18 months we expect that number to clear 700. This includes web, application, file/print, and even some database servers, as well as a handful of low-utilization domain controllers. All of the development servers are virtualized, including the SQL systems, because they are low-utilization systems. Most of our SQL work has been moved off to SQL clusters (on physical machines), though some systems retain their own dedicated SQL installations, which in most cases are physical machines for production use.