> From: Philip Rhoades
> I can ssh from/to the host/guest OK but how do I set up a route (or
> whatever is necessary) so that another machine:
> eth0: 192.168.0.12
> can ssh to the guest? - "ssh 192.168.122.68" gives "no route to host" -
> http://docs.fedoraproject.org/virtualization-guide/f12/en-US/html/ but
> the problem does not seem to be covered there.
Alexander is correct in saying that bridging would allow you to do that.
There are two networking discussed in the guide.
The first is a NAT (network address translation), in which the guests are
given "private" ip addresses and any outbound traffic appears to be coming
from the host machine's IP address. This is the same as the setup on your
ADSL router where the internal network machines get addresses of
192.168.x.x but the internet sees your requests as coming from the IP
address of your router.
There should be lots of documentation in linux firewalling guides under
sections on NAT (or possibly called IP Masquerading in some). Have a look
at these for information on port forwarding to reveal services
inside the virtual (such as ssh).
The other option is bridging. This shares the physical network interface
of the host with the guest. In this case the VM acts as though it's a
machine plugged into the same subnet as the host, its services are
accessible like those of the host and it's as vulnerable to attack as the
Yesterday I setup a Windows XP guest on a new F12 machine. Everything
This afternoon, the guest has lost network connectivity and has given
itself a 169.254. address as a result.
No DHCP requests are now being logged from the guest, whereas the
dnsmasq log showed them coming in all morning.
I would be grateful for any suggestions on how to investigate this.
I posted this on the test list since it is ff13, but perhaps
there might be more insight on the virt list:
I just tried running my Windows XP KVM on fedora 13
(I installed the KVM under fedora 12). It seemed to work
well, but I'm using the redhat virtio drivers for
network and disk, and Windows insisted on re-installing
the drivers (claiming "new hardware") the first time
I booted under fedora 13 libvirtd.
Strangely, when I booted the same KVM after going back
to fedora 12 on the host, it didn't insist on
re-installing the drivers yet again.
None of this triggered any Windows activation nonsense
(which is why it is only annoying).
I guess I should poke around in the windows hardware
manager for the details of what changed, but it would
sure be nice if things wouldn't change at all :-).
Does the libguestfs 1.0.85 found on EPEL repository support qemu-kvm
for KVM or does it use pure qemu?
While running guestfish and other utilities of the family I get an
warning about kqemu kernel accellerator and the whole thing works
slowly (seems that it uses qemu).
I thought of writing some information about running Fedora 12 Xen guests
and also Fedora 12 Xen hosts/dom0.
Fedora 12 includes the upstream Linux pv_ops Xen domU support in the default kernel.
By using virt-install or virt-manager you can install Fedora 12 Xen PV
(paravirtual) guests directly from network, for example on RHEL 5.4,
CentOS 5.4, or Fedora Xen dom0/host.
If you want to run Fedora 12 Xen dom0 (host), there are some extra steps
needed. Fedora 12 ships with Xen hypervisor and management tools
(Xen 3.4.1, and Xen 3.4.2 in the F12 updates), but the required Xen dom0
capable host kernel is not included in Fedora atm/yet.
General information about Xen dom0 status in Fedora:
There are a couple of different ways to get and install a Xen dom0
capable kernel to Fedora 12 host:
- By using pre-packaged pv_ops xendom0 kernel rpms by M A Young. his repository:
- Compiling and installing Xen dom0 capable kernel yourself/manually.
There are many options to choose from, full list of the available Xen
dom0 capable kernels is here:
The recommended dom0 kernel is the pv_ops kernel, which is in the
process of being cleaned up for upstream/mainline Linux inclusion.
More information about pv_ops dom0 kernel, including the status
Xen developers are interested of both the success and failure reports
when using the Xen pv_ops dom0 kernel.
Tips for running Xen with Fedora 12:
- Make sure you install all the latest Fedora 12 updates, since they
have an updated Xen version (3.4.2), and also fix a bug in
python-virtinst tool to make Xen guest console keymaps work properly:
- Recent versions of Xen pv_ops dom0 kernel renamed some xen
backend driver modules to have "xen-" prefix in them, for
example evtchn module became xen-evtchn. Fedora Xen 3.4.2 init
scripts take care of this, and load the correct modules, but
Xen 3.4.1 doesn't do this automatically, causing xend fail to
start in dom0/host before the modules are loaded manually.
- There are some upcoming apic-related changes coming in pv_ops
dom0 kernel, which will require a patch to Xen hypervisor.
This patch is not yet included in the Fedora Xen rpms.
The patch will be added to Fedora Xen rpms when the upstream
pv_ops kernel starts to require/use it.
- pv_ops dom0 kernel currently lacks blktap2 support, so using
tap:aio: backend disk image files is not yet possible.
Xen file: backend image files work though.
At the moment it's recommended to use LVM volumes for guest
disks (Xen phy: backend).
- virt-manager seems to work OK on Fedora 12 Xen dom0.
- If you experience problems related to Fedora 12 guests (domU)
kernel crashing (especially related to save/restore/migration),
install the latest Fedora updates to the guest. There has been
a lot of Xen guest related fixes in the upstream Linux recently.
These fixes will appear in Fedora when the kernel gets updated
to include the latest stable upstream fixes.
Hopefully that helps :)
I am missing some features from xen in KVM, specially sending special keys
to guest or watching console.
With XEN there was "xm sysrq" command to send magic-keys to guest. How can
I send special keys to qemu/kvm using virsh? Is it possible?
Sometimes I need to sync data to guest disks (for example before disk
snapshot). It is possible to do this using qemu sendkey command, but I don't
know, how to do this on qemu managed guests.
Next thing is serial console. I have serial console on my guests, but when
kernel crashes or something else happens, I can't check what happened.
With xen by starting "xm console" displays all chars logged on console after
last "xm console" command. With qemu/kvm only new characters are displayed.
Can I configure libvirt to log all all characters received on virtual serial
console to file and at the same time to allow "virsh console" command?
And latest question. I am trying to play with cluster* packages. Is there
some howto for virtualization setup? Especially I am trying to set autostart
for virtual machines, but only if there is no same machine running on
different host. When some host goes off, I need to start it on alternate
host, but when it's started back, some VMs can start on 2 hosts at same
time, what can destroy data on my shared disks.
what is current status of virt-preview for Fedora 12? Looks like current
version does not work for me and there are no latest packages available.
I am looking for these announced packages:
With current versions I can't boot from network (PXE boot). This message is
displayed, when trying to boot:
Cannot boot from non-existent NIC
My guest configuration:
<type arch='i686' machine='pc-0.11'>hvm</type>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2'/>
<target dev='vda' bus='virtio'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x04'
<address type='pci' domain='0x0000' bus='0x00' slot='0x05'
My vlan242 is UP, after downgrade to Fedora 12 stable packages works again,
but does not work with virt-preview packages.
My major concern is Libvirt 0.7.1-15. Regardless virt-install still works fine
installing PV & HVM DomUs at Xen 4.0-rc7 (2.6.10 pvops) Dom0 on top of F12. "virsh create" ,with virsh been compiled against Libvirt 0.7.1-15, fails to create new domain ( for OSOL 134 in particular). Seems like old Xen driver has to be updated.
--- On Fri, 3/26/10, Pasi Kärkkäinen <pasik(a)iki.fi> wrote:
From: Pasi Kärkkäinen <pasik(a)iki.fi>
Subject: Re: [Fedora-xen] Xen version for Fedora 13
To: "Bill Davidsen" <davidsen(a)tmr.com>
Cc: xen(a)lists.fedoraproject.org, "M A Young" <m.a.young(a)durham.ac.uk>
Date: Friday, March 26, 2010, 8:35 AM
On Thu, Mar 25, 2010 at 01:20:49PM -0400, Bill Davidsen wrote:
> Pasi Kärkkäinen wrote:
>> Should we update Xen version to 4.0.0 (-rc7) for F13? All the new pvops
>> dom0 kernel trees require the new IOAPIC stuff from either Xen 3.4.3 or
>> 4.0.0 anyway.
>> xen-4.0.0-rc7 src.rpm from M A Young seems to work OK for me:
> If you don't update you are stuck with the problems in the old version.
> If you update now you have a path to a working version.
>> Xen 4.0.0 is expected to get final soon, so we could then update the final release
>> for F13.
>> What do you guys think?
> Doesn't look like a hard choice here, the alternatives are patch 3.4.3
> to make it work right, or not get it in the release. I doubt it will get
> added if it isn't there to start, and patching obsolete code is pretty
> much a no-go, as well. Fedora is cutting edge, time to move.
Yeah, I agree.
Xen 4.0.0-rc8 is the latest release now, and it's supposed to be the last rc..
Gerd: Would you like to update the Fedora xen rpm?
xen mailing list
On 03/23/2010 03:44 PM, Ales Kozumplik wrote:
> Hi Liam,
> On 03/23/2010 04:03 AM, Li Ming wrote:
>> If it works on F13, do we have some specific steps?
>> 1. how to tell anaconda to open /dev/virio-ports/...ananconda.log,pass
>> some args during boot? or this is default?
> This is not implemented, open a bug for this and assign it to me please.
> It's not going to make F13 probably.
Thanks Ales,I filed a bug :