How do you disable hpet in a kvm?
by Fred Brier
I installed PBX In A Flash (PIAF) as a VM on a Fedora 11 64 bit host.
PIAF is a 32 bit CentOS 5.2 distro for running Asterisk. I, like many
others, am getting the error message "rtc: lost some interrupts at
1024hz" repeating over and over on the console. Some people have
apparently gotten rid of this error message by disabling hpet in the
BIOS. However, this is a VM (kvm).
I tried adding nohpet as a kernel parameter in /boot/grub/menu.lst, but
that effects the linux OS, not the BIOS. It did not fix it.
I found references to a -no-hpet qemu parameter. However, I cannot find
how to set it in a VM created using virt-manager and an ISO image. In
the /etc/libvirt of the host I found XML configuration files describing
the VMs. These appear to be the same as those created using the virsh
dumpxml command. There does not appear to be an XML element as there is
for acpi and apic. The man page describing the XML format does not have
an HPET related option. I could not find an example or sample of it
being disabled in a libvirt XML file. Nor does there appear to be a
schema (xsd or dtd) for the libvirt file format, which might have had an
hpet element or attribute.
Ideally, is there a way to disable HPET in the BIOS for a specific VM,
and not all VMs. Thank you.
Fred
//
13 years, 10 months
Disable screen powerdown on vms
by Thomas S Hatch
On a regular redhat/fedora system booting into runlevel 3, the screen shuts
down after a few minutes of being idle. I have some finicky clients, and
when they open up a console to a vm they get scared (still) when it is all
black. Where is the setting to prevent the vm from trying to powersave a
non-existent screen?
-Tom Hatch
13 years, 10 months
Losing sound in Win XP qemu-kvm guest
by jah
I'm running a Windows XP (32-bit) guest on my Fedora 13 x86_64 Gnome
desktop system using command line qemu-kvm. In XP I'm using the Sound
Blaster card as the default as it has better sound. The Intel card
warbles and the sound breaks up. After running the guest for a day or
two I lose sound. If I switch to the Intel card I get sound back but
like I said, the Intel card doesn't work as well. I have a multiboot
system and when I boot into Gentoo I have the same problem if I run KVM
as a module. When it's compiled into the kernel I do not have this
problem. In Gentoo the Intel card seems to have better sound but
switching cards after loosing sound doesn't usually restore it. I log
into Gnome using my non-privileged account but run qemu-kvm as root (my
user is in the kvm and audio groups however) using this command line:
/bin/nice -n-19 /usr/bin/qemu-kvm \
-hda ${DIR}/${IMAGE} \
-vga std \
-no-quit \
-no-frame \
-name "Windows XP" \
-usb \
-usbdevice tablet \
-daemonize \
-soundhw all \
-localtime \
-m 3584 \
-mem-path /hugepages \
-monitor telnet:127.0.0.1:4444,server,nowait \
-net nic,vlan=0,model=virtio,macaddr=00:1b:fc:9a:75:21 \
-net tap,vlan=0
selinux is running in permissive mode. I have an Asus M2R32-MVP
motherboard with integrated audio, 8gb memory and an AMD Phenom 9950
Quad-Core Processor. The audio device is:
00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA)
Subsystem: ATI Technologies Inc SBx00 Azalia (Intel HDA)
Flags: bus master, slow devsel, latency 64, IRQ 31
Memory at f7bf4000 (64-bit, non-prefetchable) [size=16K]
Capabilities: [50] Power Management version 2
Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit+
Kernel driver in use: HDA Intel
Kernel modules: snd-hda-intel
My script exports QEMU_AUDIO_DRV=alsa before starting the guest. I just
realized that I forgot to change it to QEMU_AUDIO_DRV=pa when I starting
using Fedora. Obviously it still works set as alsa and I doubt that is
the cause of my problem since I have the same problem in Gentoo when
running KVM as a module. I'll give QEMU_AUDIO_DRV=pa a try the next
time I restart the guest but would appreciate any info on known issues
or advise on the best audio settings so that hopefully I won't lose my
sound. I have dual monitors and leave XP running all the time on the
right monitor. I long for the day when I don't have anything that needs
to run in Windows and I can be Microsoft free but in the mean time
running XP in a virtual jail is a lot better than running it natively.
Getting sound working correctly would be nice in the mean time.
-jah
13 years, 10 months
Allow everyone access to kvm virtual machines
by Ask Bjørn Hansen
Hi,
We have a Fedora box with a couple of virtualized windows boxes (under KVM) for testing. With Fedora 11 everyone seemed to have access by default to run/see the machines under virt-manager.
Since upgrading to Fedora 12 a few days ago until root has access -- I tried editing libvirtd.conf as described in http://libvirt.org/auth.html (setting none for the sockets and such), but I'm having no luck. Any hints?
- ask
13 years, 11 months
performance regressions in Fedora 13?
by Kenneth Armstrong
I used kvm/virt-manager heavily in Fedora 11 (helped me a GREAT deal
in getting my RHCT).
Now, I'm trying to use it again in Fedora 13 to prepare for my RHCE,
but I'm finding it a LOT slower. I can't install with an ISO image on
my external driver (using ntfs-3g), it keeps failing with a
permissions error. However, if I copy my ISO over to my home folder,
and it picks it up. I also tried using the actual RHEL 5.5 and 5.4
CD's that I have to install from, but even though it's mounted and I
can view the contents in Nautilus, virt-manager says that /dev/sr0 has
no media present.
So I tried to store the (preallocated raw) VM image on my external
driver, but that fails too. So I have to have my VM virtio disk file
on the same hard drive that the ISO is on trying to do the install,
which takes nearly 20 hours installing RHEL 5.4.
I did manage to get 5.5 installed before on this (by leaving it
running overnight), but the performance was terrible.
Also, I thought Fedora 13 was supposed to automagically set up virtual
bridges for the VMs to use, but the only option I have is NAT, it says
that there are no bridges configured, even though I have a virbr0
interface when I run ifconfig.
Any help would be appreciated, as I have no desire to install VritualBox.
-Kenny
13 years, 11 months
