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Red Hat, Novell To Package Xen
robyannetta writes "Watch out VMware and Microsoft. Here comes
Xen, an open-source virtualization for the Linux environment being pushed by Red Hat and Novell. Xen has also joined forces with leading Linux distributors, chip vendors and platform vendors to create a consortium that will more broadly enable open-source virtualization development and deployment." We've covered Xen before, but it's cool to see the momentum behind it growing, as more choice is a Good Thing.
Oh my, it all makes sense now.
Sigs cause cancer.
I just hope they get rid of the jumping puzzles this time.
This is sad but it's the truth... Where are we going
http://www.cl.cam.ac.uk/Research/SRG/netos/xen/
'Watch out VMware and Microsoft'? If im correct, Vmware and VPC doesnt require the host operating system to be actually ported to the virtual system, whereas Xen does. This might be fine for specific usage, but its next to useless for what I use vmware for - trying out new and interesting operating systems, configurations or such. The markets may overlap near the top end, but I see no reason why VMware/VPC need watch out, as the main market for these VMs is running Windows, and while there has been a developers port of WinXP to Xen, I severely doubt you will see that in the wild.
Does Xen have a website yet? It would be nice to have a link.
My, the trolls are out tonight...
To fight the war on terror, stop being afraid.
I did not know you could package up an entire alien race!?!
There is no sig
Xen
10b||~10b -- aah, what a question!
I can't find a website for this 'Xen'... I guess if it is that new G00gle hasn't indexed it yet? Oh wait, here it is XEN WEBSITE
Watch out VMware and Microsoft.
Why Microsoft?
From TFA:
Xen does not support Windows today because it uses a technique called para-virtualization to achieve high performance that involves modifying the operating system kernel, Pratt said. However, the debut of virtualization features in next-generation CPUs from Intel and AMD will make it easier to support unmodified operating systems, Pratt said.
As usual slashdot is overhyping or just getting shit plain wrong in article summaries. This is yet another usermode linux clone it seems. This is probably not very different from the "revived" plex86. VMWare is fine where it is for the time being, and it still appears OSS cannot muster the will and/or talent to produce a viable alternative to VMware.
It doesn't support Windows, so who really gives a damn?
I've always wanted to run a Debian session from within RedHat. /sarcasm I suppose it's cool for developers who need to support multiple distributions, but yawn to the rest of us.
I already use VMWare, and while I love the concept, I have had several problems, especially in using it to test newer versions of OS's. (Fedora Core 3, for example, could not load the kernel properly, while it wouldn't even recognize the disc for Fedora Core 2. Yes, I checked the checksum, yes, it matched.)
It would be great if someone could come up with a better (and free) alternative to it, hopefully some of these bugs can be worked out. I would certainly like to see all the "good" features kept, such as auto-switching between guest and host OS just by moving in and out of the window, automatic piggybacking of the host's net connection via NAT, and the overall smoothness of the interface once you do get it running. The ability to mount an ISO image as a CD is also an excellent one.
To fight the war on terror, stop being afraid.
Kim Jong II is dying.
Microsoft VirtualPC
Watch out, here it comes. An "open-source virtualization" something or other. WOW! Is it also robust and oriented toward our needs? Neat! Moles and trolls, moles and trolls.
Xen is a Good Thing (TM).
Laws are for people with no friends.
The submitter of this article is quite obviously clueless. Xen and VMware are wildly different technologies designed for very different problems. Xen is much closer to VMWare GSX Server, which has little in common with VMWare Workstation.
for war crimes
I was an early user of 1.0, and have followed developments of Xen since. It's very nicely done, open source, and builds on existing kernels and distributions (it's not really a standalone application, but integrates with the Linux kernel and adds some userland tools).
Xen lets you configure one physical system with multiple virtual systems. Hardware access (disk, net, video) is transparent via software.
This is kind of the conceptual opposite tools like Condor and Globus: rather than bundling lots of physical systems together as one (aka, grid computing), it is meant to take one system and subdivide. This makes for easier development (including testing for grid services, Web services, different distros, etc.), and of course is good for virtualization (like in Web hosting services).
Congrats, team!
Liar.
http://xen.terrabox.com/index.php/What%20is%20xen
or this:
http://www.cl.cam.ac.uk/Research/SRG/netos/xen/
???
there are too many xen pages out there?
anyone knows?
Open-Source Alternative To VMware
Open-source virtualization consortium to debut
By Paula Rooney, CRN
5:16 PM EST Wed. Dec. 01, 2004
Watch out VMware and Microsoft. Here comes Xen.
Xen, an open-source project with growing ties to Red Hat, Novell and Hewlett-Packard, is emerging as the leading contender for providing open-source virtualization for the Linux environment.
Ian Pratt, the founder of the Xen project that originated from the University of Cambridge in England, confirmed that developers from Red Hat and Suse are preparing "testing packages" of Xen that will be released in the near future.
Additionally, Xen has joined forces with leading Linux distributors, chip vendors and platform vendors to create a consortium that will more broadly enable open-source virtualization development and deployment.
Xen backers are hopeful that support from heavy hitters in the Linux industry will make Xen a household name in the open-source community. The open-source project completed the first major update of Xen version 2.0 in November.
Steven Hand, another computer scientist at the University of Cambridge's computer lab, said he expects the Red Hat drop will be available in the same time frame as Red Hat Enterprise Linux 4.0, which is due in the first quarter of 2005.
"Red Hat's packaging Xen in the near future as part of Fedora. We've talked to Suse," said Hand. "We have a lot of momentum in the open-source community. Now we're pushing into mainstream Linux so when Xen goes into the latest versions of Linux, users can compile a Xen kernel out of the box."
Red Hat will release test builds for Red Hat Fedora Core 3, and Novell will soon release test builds for Novell Suse Linux, Pratt said. The Xen components will be dropped into experimental Linux packages, but they won't be commercially supported.
Xen does not support Windows today because it uses a technique called para-virtualization to achieve high performance that involves modifying the operating system kernel, Pratt said. However, the debut of virtualization features in next-generation CPUs from Intel and AMD will make it easier to support unmodified operating systems, Pratt said.
"At that time we will reconsider Windows support," he said.
Neither Red Hat nor Novell would comment on their plans with Xen. A Novell spokesman said the company is "excited about what Xen is doing. But it's premature at this point for us to talk publicly about our strategy and potential partnerships around virtualization."
Xen will be available under the General Public License; some components may be available under a NetBSD-style license, Hand said.
Consultants and solution providers in the open-source market said they would welcome an alternative to VMware and Virtual Server, but Xen needs to add support for Windows. VMware supports Linux but is often an expensive add-on to an open-source stack, other observers said.
"Xen is very, very good, but it does not yet support Windows," said Chris Maresca, senior partner at Olliance Group, Palo Alto, Calif. "A lot of people use VMware to support WinX on Linux."
Ironically, Microsoft Research provided funding for the Xen group when it was founded two years ago, but has since back out, Xen officials said.
Xen is only one of several open-source projects devoted to offering virtualization software for the open-source and Linux environment.
Bochs, an open-source project founded in 1994 that evolved into Plex86, focused on Linux virtual machines. Observers said Plex86's approach is more like VMware's. Founder and developer Kevin Lawton said he talked with IBM, Red Hat and Novell about getting backing for the Linux VM project in 2003, but those discussions didn't pan out.
The existing code, he said, is very experimental in nature and needs additional development before it could be classified as a "version 1.0" commercially ready server. The last update of Plex86 posted in December 2003. The project is n
[root@ root]# yum install xen #yeah like this will really work /lib/modules/2.6.9-1.6_FC2/|grep -i xen /var/cache/yum/|grep -i xen
Gathering header information file(s) from server(s)
Server: Fedora Core 2 - i386 - Base
Server: Fedora Core 2 - i386 - Released Updates
Finding updated packages
Downloading needed headers
Cannot find a package matching xen
No actions to take
[root@ root]# find
[root@ root]# find
[root@ root]#
I've yet to try Xen, but as of now, I just need basic windows compatibility to launch closed softwares (most of them being databases of law articles on CD-ROM to copy / paste extracts in linux Openoffice for research purpose), and Qemu does just that.
I only wish it could play GTA3-VC !
http://xen.terrabox.com/index.php/HomePage
sweet....
Anyone noticed this on the xen web site;-
Work on Xen has been supported by UK EPSRC grant GR/S01894, Intel Research, HP Labs and Microsoft Research.
M£ contributing to F/OSS. OK, which universe is this?
But what do you have to change ? First of all, the system has to be made aware that it's not the "top top". Its physical memory is no longer contiguous (you ask Xen for memory pages, and it gives them to you in arbitrary places), it also has to be aware of absolute time that's no longer tick++. Second, you need drivers for the abstract network card and disk. Those are generally easy to write, because you just delegate the real work to Xen. VMWare is already doing something similar with its vmxnet driver for Windoze.
I'd really expect these kind of changes to the OS to be incorporated in the main linux tree, as they mature.
What do you gain from all this ? Well, SPEED. I mean, SPEED. Take a look at their research papers (wrong suggestion for the "I won't RTFA" crowd, but still ...). Their slowdowns/throughput losses (they run Postgres and Apache on a couple of virtual nodes, as opposed to a single, consolidated machine), are negligible (less than 10%). On some configurations they even got performance improvements! At the same time, VMWare and UML do considerably worse.
In general, it's very easy to "virtualize" stuff that's running mostly in user space. As soon as you have considerable OS+I/O overhead, your performance drops significantly. The para-virtualization approach (employed by Xen), pretty much gets you the best of both worlds.
The Raven
Imagine a beowulf cluster running Xen hosting Tomcat. Ahh, the joys of running virtual machines on a virtual machine that's part of a giant virtual machine. Uhh, Bob, how far away from the hardware are we now?
Novell's Zenworks, which rendered 1000 NT4 PC's/night useless on a regular basis while I was in college.
09f911029d74e35bd84156c5635688c0
VMware works with a host operating system to provide a complete x86 virtual environment for a guest operating system.
Xen is an operating system in its own right. It's a "virtual machine monitor" or "hypervisor". It can spawn multiple guest operating virtual machines.
x86 is not a very good architecture for virtualization. To have a virtualizeable architecture, anything a user-level program can do should behave the same way it would in supervisor mode, or it should trap so the virtual machine monitor can emulate it. x86 has instructions that don't quite follow this guideline -- for instance, you can see what protection ring you are currently in. In supervisor mode, you would get something like ring 0. In user mode, you get ring 3. So an operating system trying to see what ring it was in would get ring 3, but you are trying to fool it into thinking it is in ring 0.
Anyway, Xen modifies the guest architecture. It disallows these "sensitive" instructions and creates some virtual devices that are easier to emulate (like a simple software-programmed TLB). This allows the performance to be very very good, faster than VMware, but it requires you to fiddle with your operating system a bit. Which, of course, is easy to do with Linux.
-- Erich
Slashdot reader since 1997
While we're all smoking the virtualization-pipe, let's check out User-mode Linux.
That's a good question. The paper describing xen is here. I'm not sure what the implementation differences are between the two, but xen managed to achieve much better performance on certain benchmarks. So, it's functionally equivilent to UML, but faster (YMMV). Maybe someone who's not too lazy to read the paper right now can tell us what they did different.
Surely it'll get to the point where one technique XEN is employing and then butts up against a patent and then it's game over?
Alas gallinaceas de urbe bovis volo
I just hope it doesn't suck like the OTHER Xen.
"Honey, it's not working out; I think we should make our relationship open-source."
suppose a windows application doesn't run under wine
what's the best solution to run this application under linux?
bochs?
I would like to use this method instead of dual booting (only one OS at the same time).
Is there any rpm that do required modification to SuSE linux, to be able to boot it in the graphic mode using coLinux?
The coLinux site - http://www.colinux.org/
The latest version is here - http://www.colinux.org/snapshots/
I think something that folks are missing here is that Xen is not some whizzbang way to run your favorite Windows programs or to try out new versions (or completely different) of an operating system.
Xen is more similar to VM; it's already great for server farms and when things like OpenSSI become available/usable it'll mean the realization of network-wide clustering that's Tannenbaum's wet dream.
VMware/Qemu/Plex86 might be [aguably] good for those who only pretend to use their computer, but they're absolute piss for Real Work(tm).
Intel is actively working on adding hardware virtualization (Vanderpool) to its lineup of x86 processors. This will make products, like VMWare, obsolete.
is, as the article states, business server use. Put the VM images on a SAN, run the virtualization software on the real hosts.
Then when you need some CPU power, add a real host, suspend a VM, and resume it from the new real host.
Last time I checked, all servers don't run Windows.
VMWare is an ugly hack, that will ultimately perform worse than things like UML and Xen because of the unnecessary requirement to emulate a CPU by Windows.
I wonder if Novell will create a management system, allowing point-and-click and/or programmable provisioning capabilities. They could call it ZENWorks for Xen! The manual could be called "Zen and the Art of Xen with ZENWorks"
The bit about Xen becoming a household name is bullshit. Outside geek households nobody knows waht an operating system. Most people just talk about "the computer" and can't really tell the the boundaries between their applications, web content and their cameras. They certainly don't know about operating systems and vrtualisation.
Engineering is the art of compromise.
Obviously, VMWare is much stronger than Xan by now. The only thing I feel exciting on Xan is that Xan is open source. This is really an interesting project.
Why do open source developers and linux distributors want to make linux binaries work on things were trying to get rid our selfs of? That may prevent some people from crossing over if they can just run linux foo right on there windowz box...
localhost ~ # emerge xen
Calculating dependencies
emerge: there are no ebuilds to satisfy "xen".
I used to get a headache hearing about cooperative multitasking and pre-emptive multitasking- but this virtualization process seems to be similar to the Redmond way. Are they Windozifying linux?
There are 4 ways (I think) to provide what is loosely referred to as "virtualization":
1. Hardware emulation. QEMU, VMWare, Bochs all fall in that category. QEMU is open source and is actually pretty cool - a great way to test kernels during development or testing that new ISO you're trying to put together. This method is the slowest of all since all hardware is simulated in software.
2. User Mode Linux. In this scenario the kernel is run as a user process. This method has the second most overhead. Security-wise, it is only as secure as the host system, so if there is a known userland exploit, it is vulnerable.
3. Xen. To the best of my understanding, Xen is a kernel which runs other kernels. So this architecturally similar to UML, but (if you believe them) is much better optimized. And if Xen is as exploit-free as is claimed, it should also be pretty pretty secure, though I believe only time will tell.
3. Separation. This is Linux VServer, which is a fantastic project that doesn't have the publicity engine and funding of a big university behind it. This isn't really virtualization as much as it is separation. This approach is also shared by SwSoft's Virtuozzo, FreeBSD jails and Solaris containers. Since there is only one kernel in this scenario, this method is not OS-independent, i.e. VServer only runs Linux, Jails are only for FreeBSD, etc. Performance-wise, this approach should far outrun any other method as it carries practically no overhead and takes advantage of all the existing UN*X optimization. It is also very secure, possibly most secure of all (short of hardware emulation like QEMU) since it directly addresses all known virtualization exploits such as chroot escapes. But, perhaps I'm biased...
One major difference is that UML turns Linux into a runnable program.. versus Xen which is essentially an operating system which has the sole purpose of booting guest operating systems.
The latter is good because, to the administrator, runs as multiple OS on a machine rather than running multiple applications on a server (which happen to be OS')
IMHO, this cound change the entire distribution paradigm - for example - if you wanted an email server - you just download the virtual image off the network of a linux system that already has it preinstalled and mostly set up, of if you want a web server/ldap server/dns server - same thing. It is a very nice way to have the best of a full featured linux system while at the same time the xen application os has the minimal stuff nesissary to run what you want.
Early versions of VPC only ran windows. Later, it became able to run other operating systems. Given that those early versions of VPC and Xen need OS compatibility to be specifically coded for them, what exactly is the difference between virtualization and those early versions of VPC?
--- Don't ever trust a woman until she's dead- B.B. King
I read some papers on Xen. it is certainly *not* the virtual machine to start with. It won't take unmodified version of Linux and run it. Extensive changes are required. The major benefit is high efficience compared with the 'classic VM' approach.
Given that, there is no reason why tweaks required by Xen can't be made the standard feature of the Linux Kernel. In fact, the major problem with any VM approach - either it is not efficient, or it requires some kernel tweaks. Essentially, the 'host os' and the 'guest os' need some kind of handshake, so the host properly traps interrupts from the guest, simulates them and fakes the result. Again, there is no reason why this kind of handshake and related staff can't be standardized.
Not sure is this is the actual intention of Red Hat, though. What I strongly believe - with integrated hooks VM will be clean. Just take a look at VMWare architecture: it is messy, they are jumping through the hoops, it is amazing that it works at all (and fairly efficient as well).
It turns out that x86 is just a really hard architecture to virtualize, unliked something like MIPS, for instance. So, because Xen doesn't attempt to virtualize it at the hardware level to the same extent as VMWare, they can achieve better performance.
Why all this hype about Xen? Is there really a significant market for running multiple open source operating systems simultaneously on the same machine? Last time I checked, the greater majority of uses of a virtual machine is either running Windows on another OS, or running another OS under Windows... But maybe I'm missing something cool (and profitable) about this?
on x86? That is what I want.
The terms 'OS' and 'monitor' bug me...
Xen doesn't seem like an OS by any traditional sense of the word. If it was, it could be run with just some firmware installed, rather than having ports to OSs like Linux and BSD.
Them describing it as a 'monitor' doesnt' make much sense, as it seems to have a virtualization engine itself (the term monitor makes it sound like you need other software for that).
'Hypervisor' is a wank.
How about:
"Xen is a virtual machine system, allowing you to run various guest operating systems simulatenously. Unlike VMWare, Virtual Server and others, Xen does not use or provide a software X86 CPU. Instead, Xen requires guest OSs be ported to Xen. This results in better performance."
Back in the 70's, CP/CMS on the 360 architecture was open-source. CP originally was a pure emulator: privileged machine instructions caused interrupts and were then emulated by CP. So we used to debug entire CP/CMS operating systems on top of CP, which was pretty cool. IBM eventually released a commercial version of CP/CMS called VM370.
Meanwhile a bunch of independent companies, mostly time-sharing outfits, figured out that emulating privileged instructions was, well, dumb and slow. Instead, if you modified CMS to use traps instead of executing emulated privileged instructions, it could run many times faster.
Which is why commercial timesharing outfits like National CSS, etc., were routinely able to support 250+ users on 370/168's, roughly three times the user load that IBM could support with VM370. That, and the fact that National CSS bought up every single drum drive they could find as paging devices. Ridiculously fast for the time -- nearly zero seek time, and delightfully high RPM's -- but when the bearings froze, those suckers would often burst right out of the glass case and blow holes in concrete walls.
Anyway Xen is not a new idea. It's a very old (and good) idea.
What I would like to do with it, is assign each VM of zen its own usb keyboard/mouse and video card, that way I can run 2 linux boxes all on the same machine? Unlike terminal emulation, there would be less chance of me taking out the whole pc, if one virtual machines crashed? This would be handy so my wife and kid can both use the pc at the same time, and would be energy efficient since I would only need one pc...
Let's get it all out of the way now. As geeks typically have a horrible sense of humor and always resort to the obvious and the unfunny, post all your Half-Life references here in this thread.
Twelve Step TrustABLE IT:
Virtualised Linux Standard Base (VLSB)
in Virtual Demilitarized Network Zones (VDNZ)
from Trusted Build Agents (TBA)
Back in August 11, 1998, Microsoft's Vinod Valloppillil and Josh Cohen released a memorandum titled Linux OS Competitive Analysis: The Next Java VM?, in which they predicted that Linux would become ubiquitous as a services platform. However, the title of the paper could be even more prophetic.
Consider the following.
[1] It is well known that Linux is quite portable, in fact only NETBSD comes close to the number of hardware platforms supported.
[2] What is less well known is that the Linux kernel has even been ported to run on itself, as client for a virtual Monitor platform, and even to run virtualised on other operating systems including Win2K and XP.
[3] Other operating systems, such as BSD and Sun's Solaris can also use a compatbility layer to run applications compiled for Linux directly, without the need for virtualisation.
[4]The Linux Standard Base Mission Statement is to
[5] The above standard also defines a generic subset of the standards for each hardware platform as a source level application interface. In fact for an application to be certified for the LSB it must be tested on two of the plaforms supported by the LSB, one chosen at random by the testing body. Following the standard, it's not that difficult a job to write portable C and C++ code : Write once, compile for each platfom.
[6] The GNU Compiler Collection's future GCC 4.0 Release Series now divides the task of compiling into two stages based around Static Single Assignment trees. It should be possible to use the new GCC front ends to compile each language into a SSA tree that represents the common generic subset of the Linux Standard Base: [5].The resulting SSA tree for a build could be dumped into files, analogous to Java's JVM intermediate format, and then complied to native code for the target platform: Write once, run everywhere.
Be it open or closed source, every binary or script you execute represents a risk. It is possible to introduce hostile code at any point along the build chain, before the point where the binary is checksummed and the result digitally signed.
[7] It is possible to use constraints built into any Linux or Unix like operating system to isolate and restrict what a binary executable has access to or can do. Even without employing SELinux's manditory access controls or chroot/jail'ed environments, it is possible to run a process under a different user identity and group identity. Unix servers have used this te
Well, since it's both Red Hat AND Novell, thats pretty much the kiss of death for Microsoft, isn't it?
So, if I understand right, the host OS isn't Linux. Rather, it's a stripped down "xen" system, which boots any guest OS ported to xen. From figure 1 in the paper, it looks like you control the xen system from one of the guest OSs, rather than from the host OS, like in UML.
Aren't the virtualization projects like Xen, User Mode Linux, etc. essentially reinventing the microkernel? Their goals seem awfully close to the idea of abstracting away the hardware so you can safely run multiple OS "personalities" at the same time. I wonder what could be accomplished if the virtualization guys teamed up with the people working on a modern microkernel like L4. Anyone have benchmarks comparing L4-Linux with Linux under Xen? Heck, maybe one day people will realize the advantages of a multi-server OS like the Hurd.
because it is not general purpose such that I can download and experiment on any OS I want, but I am restricted to "specially modified" version of them.
I really don't care about Windows, I want to run Darwin x86 or FreeBSD, and not just "specially modified" versions, but ANY version I so choose.
Xen cannot handle this, and that, in my view and experience, makes it relatively worthless when compared to something like VMWare. Attempting to sell the lack of a hardware virtualization layer as an "advantage" is a little odd, in my opinion, since the speed increase is not so great as to outweigh the disadvantages outlined above.
GJC
Gregory Casamento
## Chief Maintainer for GNUstep
I suspect that you could accually port NT/W2k/XP to this pretty easy without M$'s help. That is if you have a copy or can get a copy of the NT HAL development kit from M$. The kinds of operations that XEN is requiring OS changes for are already in NT as part of the kernel arch, Page insertions, TLB flushes, etc all go through common linked in routines. Unlike in linux where the routines are compiled into the kernel, NT makes calls to HAL.dll which gets linked by ntldr. Accually it probably wouldn't be to hard to do reverse engineer since the whole process is pretty well documented and the functions are public exports from the .dll.
I teach a security course around the world.
:) I don't expect MS to improve with network support - but it would be nice.
Back in the old days we were using phyiscal systems which was a nightmare, but now its all on one box. So much easier. Now instead of organising stuff to ship via special freight which would cost thousands of dollars per shipment. I carry everything on the plane onboard luggage!
For the last course I migrated the desktops to use Microsoft Virtual Machine - which was a disaster. MSVPC cannot (and probably wont) go into the promiscious mode, and a lot of the scanner and spoofing tools simply do not work.
This is not a problem with vmware as its fairly close to a true virtual environment.
MSVPC is great for business applications but thats about it - choose your software wisely
Ive since moved back to Vmware. (It was a business decision to try it out MSVPC, not technical)
Ok, Xen seems to be a OS maintainer.. sort of like what resides on the real OS of the Z series mainframes that IBM sells.
Ok, a free beer to anyone who can explain why this is different than a Roothost as Linux-uml with NSA security, and spawns via a script to copy kernel images and set up disk slices as partitions?
Xen is some 3'rd party stuff, and UML is aready in 2.6 by default. All you need to do is a "make menuconfig arch=um" to initiate... And you have built-in quota by way of partition-files and possible access by root filesystem via loopback.
Ok, why is Xen better?
Does anyone around has used Xen on a real production environment like, say, a VPS provider? What About Linux Vserver (http://www.linux-vserver.org/)?
What are the real differences, besides the technical paravirtualization of Xen and the fact that the guest OS must be 'ported' to it in order to run it, and that Linux Vserver is for running Linux only? I mean in terms of performance, feature-richness, security, stability and scalability of both the host and guest OS? What about work under non-x86 architecures, like PPC/PPC64 or native AMD64 support?
I haven't been able to decide yet which would present an ideal solution for a partitioned VPS environment, so any help from you would be greatly appreciated.
Articulos para gente geek: Poleras, linux, libros y mas
Looks like we are setting up Half Life 3 already...
Blah blah blah blahblah blah blahblah blah blahblah blah blah Next Big Thing Blah blah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blahblah blah blah Slashdot Circle Jerk blah blah blah blah blah blah blah blah blah blah blah blahblah blah blahblah blah blah...No way in hell is anything ever ever ever going to be 100% universal without two requirements: It is written in 100% Pure Java (tm), and it is Damn Sexy.
That is if you have a copy or can get a copy of the NT HAL development kit from M$.
that's one pretty damned big "if".
Disclaimer: I work for VMware, but they don't pay me to post on slashdot.
There are a lot of replies of the form, "Wait a minute, Xen requires that you hack up your guests! What a crock! Typical slashdot hype!" It's true that Xen is more limited than VMware's products, in that you do need to modify guests. However, this doesn't mean that Xen is a joke. (Plex86, for instance, really is a joke, because Kevin Lawton seems to pursue it only in fulfillment of an elaborate VMware-centered revenge fantasy.)
The Xen folks, on the other hand, are smart and mostly serious people. Xen, along with appropriately modified guests, solves some of the problems that our products solve, and for those areas where it fits the bill, it does so in a way that should have lasting performance advantages over full x86 virtualization. What Xen is not, in my opinion, is a virtual machine monitor, for any reasonable definition of VMM. Xen is a microkernel. They don't call it that, because it's hard to get papers about microkernels published these days, but if you think about it, the process of porting an OS to run as a guest under Xen isn't cocnceptually distinct from porting it to run as a personality under Mach or Chorus or whatever. The L4 people didn't even bother renaming their microkernel before repurposing it as a paravirtualization platform.
I think the microkernel analogy helps clarify ones thinking about the promises and limitations of so-called "paravirtualization." Hypervisors are microkernels. In the mid-90's, there was a hope that the whole world would be able to settle on the Mach microkernel. It never happened. Anybody hoping to become the only 'para-hypervisor' will face the same political and commercial challenges.
So to recap: Xen is not a replacement for VMware's products. Xen will probably not take over the world to the degree that its creators would like. Xen is not, however, a joke. The Xen researchers are mostly conscientious, smart people who, fairly enough, would like to see their work have some commercial impact. I really wish they'd stop beating their chests over benchmarks that show them beating a three year old version of our desktop product, though.
If a hacker gets root in a hole in Apache, only the VM instance gets compromised. Its alot like the BSD jails but more popular.
What I like about it is when I take my assembly course next year in college I can run it in a VM state. Assembly is a great way to freeze up and fuck up your computer. With Vmware or Xen I just type the code in Vim and cut n paste it in the vm session running Linux and execute the code. If it freeze its a no biggie and I just restart the session. No long reboots and lost saved work.
http://saveie6.com/
From the Xen homepage (bottom): "Work on Xen has been supported by UK EPSRC grant GR/S01894, Intel Research, HP Labs and Microsoft Research. "
So... why should Microsoft worry again?
Disclaimer: I have a licensed copy of VMware, but they don't pay me to post on slashdot.
.. is so that I can do un-Linux stuff Visual Studio.NET or Corel Draw.
Unless I read it wrong a number of times.
But what is the point - of me getting Xen - if the only reason for me having a virtual machine (and please dont get pedantic on terms)
The greatest advantage of Xen - is that the moment they released an article - Vmware's price dropped considerably to the point of being affordable.
I mean sure Xen will have its security uses for people wanting a Virtual Linux server.
However, it is possible that MS themselves may want Xen support over time. The dinosaurs have shown us that it is advantageous for an O/S to share a platform and it can give significantly more flexibility.
The issue with VMware is that it is at best a hack. It tries to locate and modify the privileged instructions of the host o/s in the binary. This will not always work.
Cambridge has a source license for XP and is very closely associated with a Microsoft research lab nearby. They did the port but unless you are a) an academic and b) also a source licensee, you won't get the source patches and don't have a hope in hell of getting the binary.
If you're using a client OS that's as non portable as Windows, hence requiring a slow partial emulation (like VMWare) or full emulation (like VirtualPC), then Qemu will happily run Windows XP on your Mac or Linux box.
But with Linux, you don't need to do that. It runs fast inside a real virtualized environment, so its virtualized performance shits all over Windows.
OSS already provides a young, but workable, VirtualPC / VMWare equivalent. Will proprietary software provide a compelling virtualizable OS as Linux?
Nihilanth? :-)
I wholeheartedly disagree with you. :)
Plex86, for instance, really is a joke, because Kevin Lawton seems to pursue it only in fulfillment of an elaborate VMware-centered revenge fantasy.
I'm not sure where you're getting this. Is it just because he's trying to create a free emulator which is *really* a useful emulator in the sense that it doesn't require you to modify guests that you think he's after revenge?
Let's be honest. People need an emulator on Linux to run something *other* than Linux under Linux. There is nothing exciting at all about an emulator which requires you to modify guests. I find nothing extraordinary about Xen whatsoever. Maybe when plex86 is done, I consider using that.
GJC
Gregory Casamento
## Chief Maintainer for GNUstep
That is my understanding. I've played with Xen a little but couldn't get it working fully on my hardware and gave up. Since it is essentially its own Operating System, you're limited to its hardware support (which makes this nearly useless in its current form as it doesn't support the scsi/raid controllers of "real servers").
It requires at least one guest OS and from there it can be managed. I'm not sure what the security restrictions on this are.
Such clauses are common for software. You're welcome to challenge them; we'd all be grateful. Until you (or someone else) mount a successful challenge, people will tend to assume that such clauses are valid and enforceable.
That's not it smartpants. The troll is ctrl-c & ctrl-v posts from other ppl in an attempt to... well... be a troll.
we do this with things internally; its nice to have a winxP build with activated office apps that I can host on my home, work, laptop.
:)
but cost of OS maintenance is proportional to the #of virtual OSs on a system, not real ones. That is, if I have 10vm images on an HDD, that is 10 platforms to keep up to date. Which isnt that expensive with Unix, but on windows, it matters. you cannot bring up a month old VM without applying IE patches to it first, for security reasons.
Summary: works best with secure operating systems. But we know how to do those, dont we
Definition of emulation "When one system performs in exactly the same way as another, though perhaps not at the same speed."
Looks like they're just trying to do what these guys are already doing! Copying but without the speed.
Hi,
there is an additional virtual machine: FAUmachine.
From the homepage:
FAUmachine is a virtual machine, similar in many respects to VMWare[tm] or Virtual PC[tm]. The FAUmachine virtual machine runs as a normal user process (no root privileges or kernel modules needed) on top of (currently) Linux on i386 hardware. The port of FAUmachine to OpenBSD and Windows is in progress.
The FAUmachine virtual machine is booted using an adapted bootloader and runs a slightly modified Linux kernel. The hardware layer of the FAUmachine virtual machine is (mostly) the Linux kernel of the host system. The FAUmachine hardware setup, like main memory size, cdrom and number and size of harddisks can be configured.
Onto this virtual hardware, an out-of-the-box Linux distribution can be installed using the installation program that comes with it. Binaries compiled for i386 hardware architecture will also run on FAUmachine. Of course FAUmachine supports networking and FAUmachines can be connected transparently to the local network which their host machine is attached to. If the appropriate servers are running on the FAUmachine, login from any real machine is possible, once the network is set up.
Xen has been around for anyone with an iota of systems management ability for a long time. So now it's available in rpm format? So f'ing what? If you are so incompetent that you require a package format like rpm before you can get something to run, you shouldn't be running it in the first place.
How's is Red Hat's business strategy anything other than a bunch of FUD?
I'm not sure where you're getting this. Is it just because he's trying to create a free emulator which is *really* a useful emulator in the sense that it doesn't require you to modify guests that you think he's after revenge?
Kevin threw up his hands a year or two ago and turned Plex86 into a Xen-like pseudo-VMM. Xen is now what plex86 aspires to be.
In my opinion someone should provide a viable and free alternative to VMWare, no offense to your employer who makes an excellent product.
GJC
Gregory Casamento
## Chief Maintainer for GNUstep
None taken, and thanks for the compliment. While I've been hard on plex86 here and in the past, the difficulties that project faced may be instructive in why a free VMware workalike has been slow to emerge.
XEN is a Virtual Machine Monitor (VMM) originally developed by the Systems Research Group of the University of Cambridge Computer Laboratory, as part of the UK-EPSRC funded XenoServers project.
Xen enables multiple operating system images to execute concurrently on the same hardware with very low performance overhead --- much lower than commercial offerings for the same x86 platform.
Hardware Abstraction Layer Read about it and learn.