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Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Red Hat has announced its virtualization strategy, which is based on moving away from Xen to KVM. "Red Hat's strategic direction for the future development of its virtualization product portfolio is based on KVM, making Red Hat the only virtualization vendor leveraging technology that is developed as part of the Linux operating system. Existing Xen-based deployments will continue to be supported for the full lifetime of Red Hat Enterprise Linux 5, and Red Hat will provide a variety of tools and services to enable customers to migrate from their Red Hat Enterprise Linux 5 Xen deployment to KVM."
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Block Paravirt Windows drivers

Posted Feb 23, 2009 21:58 UTC (Mon) by tmassey (guest, #52228) [Link]

The only thing that stops me from diving into KVM is the lack of paravirt block drivers for Windows. What is the thinking on that? Are they expecting everyone to use iSCSI? Or am I missing something?

I would like to see the paravirt Windows LAN drivers better supported, but at least they exist...

Block Paravirt Windows drivers

Posted Feb 23, 2009 22:15 UTC (Mon) by drag (subscriber, #31333) [Link]

Presumably the Paravirt driver situation will get worked out with the recent Microsoft-Redhat agreements. Pretty much the same thing that Novell did, just minus the patent 'covenant' BS.

Presumably. I haven't heard about it one way or the other. I know that their exists PV Network drivers for Windows, I think.

----------------

The one thing I am wondering about is the fantastic remote VM desktop technology that was the backbone to Qumranet's profit making strategy... That stuff is fantastic, being able to stream HD video and flash animation stuff over the network like they were able to do.

Block Paravirt Windows drivers

Posted Feb 23, 2009 22:17 UTC (Mon) by drag (subscriber, #31333) [Link]

> Red Hat Enterprise Virtualization Manager for Desktops: A new management system for virtual desktops that will deliver industry-leading VDI cost-performance for both Linux and Windows desktops, based on Qumranet's SolidICE and using SPICE remote rendering technology.

Hrmmm... Tasty. This is ground-breaking stuff there for anybody wanting to do remote desktops and whatnot.

How about a little more SPICE?

Posted Feb 23, 2009 23:56 UTC (Mon) by dowdle (subscriber, #659) [Link]

That were my main two questions when I first heard Red Hat acquired Qumranet... what will happen to SPICE and SolidICE?

See: Qumranet Joins Red Hat - Lots of questions
http://www.montanalinux.org/redhat-buys-qumranet.html

Block Paravirt Windows drivers

Posted Feb 24, 2009 1:01 UTC (Tue) by dag- (subscriber, #30207) [Link]

Do you mean this for KVM ?

http://www.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux...

Since KVM is not yet supported by Red Hat there is little customer pressure to have them. But I am sure that they need to be part of the offering once RHEL6 becomes available with KVM as default.

I doubt this is directly part of their deal with Microsoft since they are offering these for Xen already. As far as I understood the deal with Microsoft is to have RHEL supported on Hyper-V and Windows on Xen (and presummably KVM in the future too).

Block Paravirt Windows drivers

Posted Feb 24, 2009 2:35 UTC (Tue) by tmassey (guest, #52228) [Link]

Yes, that's pretty much what I'm looking for--but for KVM.

From the link you posted, I can't tell definitively, but my guess is that it only works for Xen. Also, the documentation says that you can't boot from these drivers/devices, which isn't great either.

Given that it's Red Hat's intention to drop Xen, I would hope that part of their plan is porting this type of support to KVM. It's what I'm waiting for...

Block Paravirt Windows drivers

Posted Feb 24, 2009 10:21 UTC (Tue) by danpb (subscriber, #4831) [Link]

Be patient, paravirtualized block drivers will no doubt arrive for Win32 under KVM. Paravirt network drivers are far more important for scalability, giving orders of magnitude better performance than emulated NICs. The performance boost from paravirt disk drivers, while important, is not nearly so significant and thus most work goes into NIC drivers first.

Block Paravirt Windows drivers

Posted Feb 25, 2009 14:41 UTC (Wed) by mangoo (guest, #32602) [Link]

Sometimes it pays to read kvm-devel mailing list:

http://article.gmane.org/gmane.comp.emulators.kvm.devel/2...

"We have beta code for windows pv block. We plan to publish them as soon
they will be rock stable. Scsi emulation also exist but might not be
100% stable."

The only thing to wonder is their definition of "soon".

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 3:18 UTC (Tue) by dhess (subscriber, #7827) [Link]

This article reminds me that it's about time for my semiannual LWN KVM question!

I started with KVM for virtualization but switched to Xen because, at that time, the only way to get a virtual console on a KVM guest was to run VNC and connect to the guest's virtualized VGA device. With Xen, I'm able to run "xm console domu-name" from a shell on the dom0 to get a serial console-like session. Can I now do something similar with KVM guests?

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 6:17 UTC (Tue) by wmf (guest, #33791) [Link]

Have you looked at the qemu -serial option? You may have to configure the guest for serial
console.

http://www.lrfz.com/2008/02/serial-console-for-kvmqemu.html
http://www.linux-kvm.com/content/multiplexing-your-monito...

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 6:18 UTC (Tue) by drag (subscriber, #31333) [Link]

If you configure your Guest OS to use it's virtual serial port as a console then you there are various options you can do. Things like using the nographic option so that the serial console is redirected to your current terminal, redirecting the serial to a fifo, network, stdio, etc.

Similar thing for the Qemu console (were you can use the Qemu shell to configure the VM) and that sort of thing.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 8:46 UTC (Tue) by eklitzke (subscriber, #36426) [Link]

> With Xen, I'm able to run "xm console domu-name" from a shell on the dom0 to get a serial console-like session. Can I now do something similar with KVM guests?

It's as simple as:
virsh console domu-name

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 10:25 UTC (Tue) by danpb (subscriber, #4831) [Link]

If you are using libvirt for provisioning then you can get a text based console using the emulatated serial device. Both virt-manager & virt-install will enable a serial device for all new guests installed, so you merely have to tell the guest OS to run a gettty process on it, then 'virsh console GUEST' provides the same functionality as old 'xm console' command. NB you can also use 'virsh console' for Xen paravirt & fullvirt guests, so you can avoid being locked into the 'xm' command.

For guest setup, in your grub.conf just add 'console=ttyS0 console=tty' and in /etc/inittab add a line 's:2345:respawn:/sbin/agetty ttyS0 9600'. The same is needed for Xen fullyvirt guests.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 11:57 UTC (Tue) by dhess (subscriber, #7827) [Link]

That sounds like a winner. Last time I tried the libvirt tools, they didn't support KVM very well. Thanks for the info, everyone who responded.

Pure KVM solution

Posted Feb 24, 2009 13:01 UTC (Tue) by gwolf (subscriber, #14632) [Link]

I am using pure-KVM (i.e. no libvirt), and my invocation commandline always includes this:
 -monitor unix:/var/run/kvm/lab01.socket,server,nowait
This opens the console as a unix-domain socket, to which I can connect via nc:
$ nc -U /var/run/kvm/lab01.socket 
QEMU 0.9.1 monitor - type 'help' for more information
(qemu) info kvm
kvm support: enabled
(qemu) info cpus
* CPU #0: pc=0x00000000806d8dbd thread_id=5655
(...)
Of course, this allows to drive it programatically.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 25, 2009 14:48 UTC (Wed) by mangoo (guest, #32602) [Link]

Have you tried Proxmox VE: http://pve.proxmox.com/wiki/Main_Page

It's a gem virtualization solution when compared to anything you can build yourself from Xen sources.
And yes, it allows you to connect to console as well.

If you want to run KVM standalone, it's of course possible to connect to console - just add such parameters:

-monitor unix:/var/run/qemu-server/102.mon,server,nowait
-serial unix:/var/run/qemu-server/102.serial,server,nowait

First one is Qemu monitor, second is guests's console (make sure to change /etc/inittab to launch getty on /dev/ttyS0).

You can use minicom to connect to these paths then.
Also, instead of minicom, you can launch serial console listening on part (i.e., you connect to it with telnet).

Read the manual for full details.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 6:27 UTC (Tue) by muwlgr (guest, #35359) [Link]

Citrix, having bought Xen, is clearly a dangerous risk for any attempt of free software interactions. Their ties to Microsoft are too close and intimate.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 16:31 UTC (Tue) by tzafrir (subscriber, #11501) [Link]

Citrix seems to has some reassurances for free software developers:

http://www.citrix.com/English/NE/news/news.asp?newsID=168...

(which probably desrves its own news item)

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 16:55 UTC (Tue) by muwlgr (guest, #35359) [Link]

I would just wait and see. What the corporation tells us, is not the matter to trust in.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 16:48 UTC (Tue) by drag (subscriber, #31333) [Link]

The real motivation is that KVM is just a superior design to Xen.

KVM turns the Linux kernel that is all the bit as capable of any other hypervisor avialable, you get all the Linux hardware and storage features free, and you can manage operating systems as if they are any other application.

In terms of usability it's superior also... everybody running a modern Linux system already has the core KVM code and dependencies installed and configured, by default. The only question is hardware support and almost all machines sold in the past year or so has support for it. Those that don't have the hardware support can just use Kqemu/Qemu as a stop gap and have compatible interfaces.

It took weeks and months for KVM to get the same point that took Xen years...

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 16:58 UTC (Tue) by muwlgr (guest, #35359) [Link]

KVM is simple, light and fast but it is Linux-specific.
Xen is heavier but theoretically more portable.
Its dom0 could run under other kernels than Linux.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 20:54 UTC (Tue) by drag (subscriber, #31333) [Link]

Well sure. But you can strip down Linux/KVM to the point were it's only really a hypervisor... then run the management stuff through a different OS.

So it's not really much of a advantage.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 24, 2009 18:17 UTC (Tue) by tzafrir (subscriber, #11501) [Link]

Though you have to remember that much of the virtualization interfaces on which KVM relies were written originally for VMMare and Xen and with active participation of both.

Red Hat Sets Its Virtualization Agenda (Red Hat press release)

Posted Feb 26, 2009 11:32 UTC (Thu) by epa (subscriber, #39769) [Link]

If the software (such as Xen's hypervisor and tools) is licensed in such a way that being bought by Citrix makes it risky to use, then you should not use it anyway, no matter who owns it. Pretty much any company can be bought by any other company.

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