Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[G Crowe]

Alvin,
Thanks for that. I disabled the xendomains service (I had to do it 
twice, as it seemed to re-enable itself after the first reboot) and it 
now starts libvirtd automatically on startup.


However, all is not well!
"xl list" and "virsh list" will just hang
"systemctl stop libvirtd" just hangs and after this "ps aux" lists the 
process as defunct
root   673  0.0  0.0  0 0 ?Zsl  08:04   0:00 
[libvirtd] 

"kill -KILL 673" has no effect
"shutdown -r now" also hangs (I have to physically power off the 
machine) irrespectively of whether I have tried to stop the service 
before shutdown or not.


None of this happened yesterday when I manually started libvirtd after 
bootup (when xendomains was still running).


The logs show nothing in error or warning category, just a heap of info 
(I have the logs set to level 2). Is there anything in particular that I 
should be looking for in the logs?




Regarding the use of a VM to access the host in a remote location... I 
had considered this and there was little choice. The machine is on the 
end of a VDSL line and was installed to consolidate a few servers in 
that location in order to save power. I figured that automatically 
starting a VM that ran the networking was not much more risk than a 
physical server that had to start up its networking, and that has (so 
far) proven to be true with all of the remote restarts & power outages 
to date. The only other option is an expensive second link to the host, 
and I've decided to live with the possibility of having to talk someone 
through a restart over the phone rather than go down that route.


Interestingly, with the NBN in Australia (the country-wide rollout of 
fibre or broadband to every premises) they have effectively converted 
all our phone lines to VoIP. This has resulted in the old physical 
landline now requiring one of the VMs to be running as well, so if I 
ever need to talk someone through a restart it will need to be on a 
mobile phone.



Thank you

GC


On 27/07/2017 5:47 AM, Alvin Starr wrote:

I addressed the fix to Jim but I should have addressed it to you.


Try systemctl disable xendomains.service

It is conflicting with libvirtd.service.
I found it by using
"systemd-analyze  dot libvirtd.service | dot -Tgif > /tmp/dot1.gif"


It looks like libvirt-daemon-driver-xen or 
libvirt-daemon-driver-libxl  should  disable the xendomains.service



On 07/26/2017 06:46 AM, G Crowe wrote:

Jim,
Thanks for that, I had manually installed 
libvirt-daemon-driver-xen, but also needed to install 
libvirt-daemon-driver-libxl. I can now create VMs and convert config 
formats.


However the daemon still fails to start on bootup. It starts fine 
when I manually start it with "systemctl start libvirtd" but setting 
it to autostart with "systemctl enable libvirtd" seems to have no 
effect. When I look at the status, it tells me that the service is 
"enabled" which means that it starts on bootup (well, that's what it 
means for any other service).


This is rather critical on this PC, as it has unattended restarts and 
the VPN/routing is done in one of the VMs (i.e. I can't get to it 
unless it auto-starts at least one VM).


Unfortunatley there is nothing appearing in the libvirtd log over a 
reboot to help diagnose.


Any suggestions?


Thank you

GC


[root@testhost ~]# systemctl status libvirtd
● libvirtd.service - Virtualization daemon
   Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled; 
vendor preset: enabled)

   Active: inactive (dead)
 Docs: man:libvirtd(8)
   http://libvirt.org




On 25/07/2017 1:20 AM, Jim Fehlig wrote:

On 07/23/2017 04:25 PM, G Crowe wrote:

Hi,
 I am trying to upgrade my Xen host (Dom0) and are having 
troubles getting it to work.


I think that it has booted into a kernel that supports Xen (running 
'xl info' does list some Xen capabilities), but I have three 
problems (that I have found so far).


Firstly, the "libvirtd" daemon doesn't start on bootup (and as a 
result all 'virsh' commands fail). It is set to auto-start 
(systemctl enable libvirtd), and can be manually started (systemctl 
start libvirtd), but it will not auto-start on reboot.


Secondly, Once I have manually started libvirtd, when I try to 
define a domain it gives me an error "could not find capabilities 
for arch=x86_64 domaintype=xen" and I haven't yet been able to 
define any domains. This domain type works fine on Fedora 21.


Thirdly, I am unable to convert to/from xml config format, it gives 
me the error "error: invalid argument: unsupported config type 
xen-xl" however the format "xen-xl" works fine on the Fedora 21 
machine.


It sounds like the libvirt libxl driver is not loaded. Is the 
libvirt-daemon-driver-libxl package installed? If it's installed, 
enabling debug logging in libvirtd can provide hints why it is not 
loading


http://libvirt.org/logging.html

Regards,
Jim



I had these same issues when I tried to upgrade to Fedora 25 

Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[Alvin Starr]

Jim:

Try systemctl disable xendomains.service

It is conflicting with libvirtd.service.
I found it by using
"systemd-analyze  dot libvirtd.service | dot -Tgif > /tmp/dot1.gif"


On 07/26/2017 10:19 AM, Jim Fehlig wrote:

On 07/26/2017 04:46 AM, G Crowe wrote:

Jim,
 Thanks for that, I had manually installed 
libvirt-daemon-driver-xen, but also needed to install 
libvirt-daemon-driver-libxl. I can now create VMs and convert config 
formats.


However the daemon still fails to start on bootup. It starts fine 
when I manually start it with "systemctl start libvirtd" but setting 
it to autostart with "systemctl enable libvirtd" seems to have no 
effect. When I look at the status, it tells me that the service is 
"enabled" which means that it starts on bootup (well, that's what it 
means for any other service).


I think you'll need to debug the startup problem via systemd, e.g. 
using systemd-analyze. Perhaps it is not starting do to conflicts with 
other services, e.g. xendomains. Do you also have xendomains service 
enabled? If so, disable it since it should not be used with libvirt.


Regards,
Jim

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Re: [libvirt-users] automatically reverting to a snapshot

[Peter Krempa]

Please configure your mail client to send plain-text version to mailing
lists ...

On Tue, Jul 25, 2017 at 16:08:58 +0100, Dirty Dan wrote:
> How can I automatically revert to a snapshot after the guest 
> is stopped?/etc/libvirt/hooks/qemu
#!/bin/sh
name="$1"
action="$2"
if [ "$name" = "name" ]; then
virsh snapshot-revert "$name" --snapshotname 
"snapshot1"
fiI tried 
this which resulted in a deadlock, then I saw the warning further down the 
page.

The hook documentation explicitly states that no calls to libvirt shoudl
be executed from the hook.

You can start a process in background, which will terminate the hook and
that process should be able to do libvirt calls.


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Description: Digital signature
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Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[Dominik Psenner]

[off topic]

One day someone had the idea to test a disaster scenario and plugged the
power supply on the server that guarded the security doors. All went quite
well until that someone wanted to enter the server room to power on that
server again. At this moment he noticed that the doors would no longer open
and there was no lock to put a key in. :-D That was a really good lesson to
learn and today it is a good joke that we can laugh about.

It is simple to have a second network cable to provide a fallback mechanism
to log into a critical component of a system. Think about such things, the
day will come when you'll be happy to have it.

[eof off topic]

For me, on the latest ubuntu lts, the libvirtd service starts up fine along
with all guests and shutdown works just fine too in the sense that the host
shuts down the guests by ACPI power off. This might be a regression in the
Fedora dist?

2017-07-26 16:28 GMT+02:00 Alvin Starr :

> I believe this problem also exists in F25.
>
> There are upsides to having a vm do the networking and I have used that
> scheme for something like a decade.
>
> The point is that libvirt should start up and start its VM's correctly.
>
> If you cannot depend on the system starting correctly then very quickly
> you cannot depend on the system at all and then your backing out to your
> switches and network cables and power supplies .
>
> My guess is that its related to libvirt trying to start before the xen
> subsystems have come up.
>
>
>
> On 07/26/2017 09:32 AM, Dominik Psenner wrote:
>
> Note that this does not help with the original problem but points out a
> critical design flaw.
>
> To me your it infrastructure design has no working disaster recovery plan.
> You should always be able to access critical functionality and from there
> be able to restore complete functionality step by step. In your case the
> outermost functionality is the vm host. You should always be able to log
> into that machine once it has all cables plugged in, regardless of what
> runs on it (or not).
>
> This means that even though you might get this to work you should rethink
> your design so that you do not have to rely on the vm that does the
> networking.
>
> On 26 Jul 2017 12:50 p.m., "G Crowe"  wrote:
>
> Jim,
> Thanks for that, I had manually installed libvirt-daemon-driver-xen,
> but also needed to install libvirt-daemon-driver-libxl. I can now create
> VMs and convert config formats.
>
> However the daemon still fails to start on bootup. It starts fine when I
> manually start it with "systemctl start libvirtd" but setting it to
> autostart with "systemctl enable libvirtd" seems to have no effect. When I
> look at the status, it tells me that the service is "enabled" which means
> that it starts on bootup (well, that's what it means for any other service).
>
> This is rather critical on this PC, as it has unattended restarts and the
> VPN/routing is done in one of the VMs (i.e. I can't get to it unless it
> auto-starts at least one VM).
>
> Unfortunatley there is nothing appearing in the libvirtd log over a reboot
> to help diagnose.
>
> Any suggestions?
>
>
> Thank you
>
> GC
>
>
> [root@testhost ~]# systemctl status libvirtd
> ● libvirtd.service - Virtualization daemon
>Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled;
> vendor preset: enabled)
>Active: inactive (dead)
>  Docs: man:libvirtd(8)
>http://libvirt.org
>
>
>
>
>
> On 25/07/2017 1:20 AM, Jim Fehlig wrote:
>
>> On 07/23/2017 04:25 PM, G Crowe wrote:
>>
>>> Hi,
>>>  I am trying to upgrade my Xen host (Dom0) and are having troubles
>>> getting it to work.
>>>
>>> I think that it has booted into a kernel that supports Xen (running 'xl
>>> info' does list some Xen capabilities), but I have three problems (that I
>>> have found so far).
>>>
>>> Firstly, the "libvirtd" daemon doesn't start on bootup (and as a result
>>> all 'virsh' commands fail). It is set to auto-start (systemctl enable
>>> libvirtd), and can be manually started (systemctl start libvirtd), but it
>>> will not auto-start on reboot.
>>>
>>> Secondly, Once I have manually started libvirtd, when I try to define a
>>> domain it gives me an error "could not find capabilities for arch=x86_64
>>> domaintype=xen" and I haven't yet been able to define any domains. This
>>> domain type works fine on Fedora 21.
>>>
>>> Thirdly, I am unable to convert to/from xml config format, it gives me
>>> the error "error: invalid argument: unsupported config type xen-xl" however
>>> the format "xen-xl" works fine on the Fedora 21 machine.
>>>
>>
>> It sounds like the libvirt libxl driver is not loaded. Is the
>> libvirt-daemon-driver-libxl package installed? If it's installed, enabling
>> debug logging in libvirtd can provide hints why it is not loading
>>
>> http://libvirt.org/logging.html
>>
>> Regards,
>> Jim
>>
>>
>>> I had these same issues when I tried to upgrade to Fedora 25 and assumed
>>> 

Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[Alvin Starr]

libvirtd is not started by systemd on my f25 laptop

so this may not be xen related.

On 07/26/2017 10:19 AM, Jim Fehlig wrote:

On 07/26/2017 04:46 AM, G Crowe wrote:

Jim,
 Thanks for that, I had manually installed 
libvirt-daemon-driver-xen, but also needed to install 
libvirt-daemon-driver-libxl. I can now create VMs and convert config 
formats.


However the daemon still fails to start on bootup. It starts fine 
when I manually start it with "systemctl start libvirtd" but setting 
it to autostart with "systemctl enable libvirtd" seems to have no 
effect. When I look at the status, it tells me that the service is 
"enabled" which means that it starts on bootup (well, that's what it 
means for any other service).


I think you'll need to debug the startup problem via systemd, e.g. 
using systemd-analyze. Perhaps it is not starting do to conflicts with 
other services, e.g. xendomains. Do you also have xendomains service 
enabled? If so, disable it since it should not be used with libvirt.


Regards,
Jim

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Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[Alvin Starr]

I believe this problem also exists in F25.

There are upsides to having a vm do the networking and I have used that 
scheme for something like a decade.


The point is that libvirt should start up and start its VM's correctly.

If you cannot depend on the system starting correctly then very quickly 
you cannot depend on the system at all and then your backing out to your 
switches and network cables and power supplies .


My guess is that its related to libvirt trying to start before the xen 
subsystems have come up.




On 07/26/2017 09:32 AM, Dominik Psenner wrote:
Note that this does not help with the original problem but points out 
a critical design flaw.


To me your it infrastructure design has no working disaster recovery 
plan. You should always be able to access critical functionality and 
from there be able to restore complete functionality step by step. In 
your case the outermost functionality is the vm host. You should 
always be able to log into that machine once it has all cables plugged 
in, regardless of what runs on it (or not).


This means that even though you might get this to work you should 
rethink your design so that you do not have to rely on the vm that 
does the networking.


On 26 Jul 2017 12:50 p.m., "G Crowe" > wrote:


Jim,
Thanks for that, I had manually installed
libvirt-daemon-driver-xen, but also needed to install
libvirt-daemon-driver-libxl. I can now create VMs and convert
config formats.

However the daemon still fails to start on bootup. It starts fine
when I manually start it with "systemctl start libvirtd" but
setting it to autostart with "systemctl enable libvirtd" seems to
have no effect. When I look at the status, it tells me that the
service is "enabled" which means that it starts on bootup (well,
that's what it means for any other service).

This is rather critical on this PC, as it has unattended restarts
and the VPN/routing is done in one of the VMs (i.e. I can't get to
it unless it auto-starts at least one VM).

Unfortunatley there is nothing appearing in the libvirtd log over
a reboot to help diagnose.

Any suggestions?


Thank you

GC


[root@testhost ~]# systemctl status libvirtd
● libvirtd.service - Virtualization daemon
   Loaded: loaded (/usr/lib/systemd/system/libvirtd.service;
enabled; vendor preset: enabled)
   Active: inactive (dead)
 Docs: man:libvirtd(8)
http://libvirt.org





On 25/07/2017 1:20 AM, Jim Fehlig wrote:

On 07/23/2017 04:25 PM, G Crowe wrote:

Hi,
 I am trying to upgrade my Xen host (Dom0) and are
having troubles getting it to work.

I think that it has booted into a kernel that supports Xen
(running 'xl info' does list some Xen capabilities), but I
have three problems (that I have found so far).

Firstly, the "libvirtd" daemon doesn't start on bootup
(and as a result all 'virsh' commands fail). It is set to
auto-start (systemctl enable libvirtd), and can be
manually started (systemctl start libvirtd), but it will
not auto-start on reboot.

Secondly, Once I have manually started libvirtd, when I
try to define a domain it gives me an error "could not
find capabilities for arch=x86_64 domaintype=xen" and I
haven't yet been able to define any domains. This domain
type works fine on Fedora 21.

Thirdly, I am unable to convert to/from xml config format,
it gives me the error "error: invalid argument:
unsupported config type xen-xl" however the format
"xen-xl" works fine on the Fedora 21 machine.


It sounds like the libvirt libxl driver is not loaded. Is the
libvirt-daemon-driver-libxl package installed? If it's
installed, enabling debug logging in libvirtd can provide
hints why it is not loading

http://libvirt.org/logging.html 

Regards,
Jim


I had these same issues when I tried to upgrade to Fedora
25 and assumed that something had been broken and so
abandoned further attempts to upgrade, however since
Fedora 26 is the same I am now assuming that I have
stuffed something up myself (or missed something).

Fedora 21 uses kernel 3.19.3 and xen 4.4.1
Fedora 26 uses kernel 4.11.8 and xen 4.8.1

I have tried following the info on
https://wiki.xen.org/wiki/Fedora_Host_Installation
 but
it appears to be out of date now (I used this site when I
started using Xen under Fedora 19, and when I upgraded to
Fedora 21)

Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[Jim Fehlig]

On 07/26/2017 04:46 AM, G Crowe wrote:

Jim,
 Thanks for that, I had manually installed libvirt-daemon-driver-xen, but 
also needed to install libvirt-daemon-driver-libxl. I can now create VMs and 
convert config formats.


However the daemon still fails to start on bootup. It starts fine when I 
manually start it with "systemctl start libvirtd" but setting it to autostart 
with "systemctl enable libvirtd" seems to have no effect. When I look at the 
status, it tells me that the service is "enabled" which means that it starts on 
bootup (well, that's what it means for any other service).


I think you'll need to debug the startup problem via systemd, e.g. using 
systemd-analyze. Perhaps it is not starting do to conflicts with other services, 
e.g. xendomains. Do you also have xendomains service enabled? If so, disable it 
since it should not be used with libvirt.


Regards,
Jim

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Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[Dominik Psenner]

Note that this does not help with the original problem but points out a
critical design flaw.

To me your it infrastructure design has no working disaster recovery plan.
You should always be able to access critical functionality and from there
be able to restore complete functionality step by step. In your case the
outermost functionality is the vm host. You should always be able to log
into that machine once it has all cables plugged in, regardless of what
runs on it (or not).

This means that even though you might get this to work you should rethink
your design so that you do not have to rely on the vm that does the
networking.

On 26 Jul 2017 12:50 p.m., "G Crowe"  wrote:

Jim,
Thanks for that, I had manually installed libvirt-daemon-driver-xen,
but also needed to install libvirt-daemon-driver-libxl. I can now create
VMs and convert config formats.

However the daemon still fails to start on bootup. It starts fine when I
manually start it with "systemctl start libvirtd" but setting it to
autostart with "systemctl enable libvirtd" seems to have no effect. When I
look at the status, it tells me that the service is "enabled" which means
that it starts on bootup (well, that's what it means for any other service).

This is rather critical on this PC, as it has unattended restarts and the
VPN/routing is done in one of the VMs (i.e. I can't get to it unless it
auto-starts at least one VM).

Unfortunatley there is nothing appearing in the libvirtd log over a reboot
to help diagnose.

Any suggestions?


Thank you

GC


[root@testhost ~]# systemctl status libvirtd
● libvirtd.service - Virtualization daemon
   Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled;
vendor preset: enabled)
   Active: inactive (dead)
 Docs: man:libvirtd(8)
   http://libvirt.org





On 25/07/2017 1:20 AM, Jim Fehlig wrote:

> On 07/23/2017 04:25 PM, G Crowe wrote:
>
>> Hi,
>>  I am trying to upgrade my Xen host (Dom0) and are having troubles
>> getting it to work.
>>
>> I think that it has booted into a kernel that supports Xen (running 'xl
>> info' does list some Xen capabilities), but I have three problems (that I
>> have found so far).
>>
>> Firstly, the "libvirtd" daemon doesn't start on bootup (and as a result
>> all 'virsh' commands fail). It is set to auto-start (systemctl enable
>> libvirtd), and can be manually started (systemctl start libvirtd), but it
>> will not auto-start on reboot.
>>
>> Secondly, Once I have manually started libvirtd, when I try to define a
>> domain it gives me an error "could not find capabilities for arch=x86_64
>> domaintype=xen" and I haven't yet been able to define any domains. This
>> domain type works fine on Fedora 21.
>>
>> Thirdly, I am unable to convert to/from xml config format, it gives me
>> the error "error: invalid argument: unsupported config type xen-xl" however
>> the format "xen-xl" works fine on the Fedora 21 machine.
>>
>
> It sounds like the libvirt libxl driver is not loaded. Is the
> libvirt-daemon-driver-libxl package installed? If it's installed, enabling
> debug logging in libvirtd can provide hints why it is not loading
>
> http://libvirt.org/logging.html
>
> Regards,
> Jim
>
>
>> I had these same issues when I tried to upgrade to Fedora 25 and assumed
>> that something had been broken and so abandoned further attempts to
>> upgrade, however since Fedora 26 is the same I am now assuming that I have
>> stuffed something up myself (or missed something).
>>
>> Fedora 21 uses kernel 3.19.3 and xen 4.4.1
>> Fedora 26 uses kernel 4.11.8 and xen 4.8.1
>>
>> I have tried following the info on https://wiki.xen.org/wiki/Fedo
>> ra_Host_Installation but it appears to be out of date now (I used this
>> site when I started using Xen under Fedora 19, and when I upgraded to
>> Fedora 21)
>>
>> Does anyone have any suggestions? outputs from "xl info" and the domain
>> config are below. I have also tried disabling SELinux, but it made no
>> difference.
>>
>>
>> Thanks
>>
>> GC
>>
>> ---
>> On the fedora 26 box.
>> # xl info
>> host   : family.mydomain.mytld
>> release: 4.11.8-300.fc26.x86_64
>> version: #1 SMP Thu Jun 29 20:09:48 UTC 2017
>> machine: x86_64
>> nr_cpus: 4
>> max_cpu_id : 3
>> nr_nodes   : 1
>> cores_per_socket   : 4
>> threads_per_core   : 1
>> cpu_mhz: 2712
>> hw_caps: b7ebfbff:77faf3bf:2c100800:000
>> 00121:000f:009c67af::0100
>> virt_caps  : hvm hvm_directio
>> total_memory   : 8072
>> free_memory: 128
>> sharing_freed_memory   : 0
>> sharing_used_memory: 0
>> outstanding_claims : 0
>> free_cpus  : 0
>> xen_major  : 4
>> xen_minor  : 8
>> xen_extra  : .1
>> xen_version: 4.8.1
>> xen_caps   : 

Re: [libvirt-users] Xen died - Fedora upgrade from 21 to 26

[G Crowe]

Jim,
Thanks for that, I had manually installed 
libvirt-daemon-driver-xen, but also needed to install 
libvirt-daemon-driver-libxl. I can now create VMs and convert config 
formats.


However the daemon still fails to start on bootup. It starts fine when I 
manually start it with "systemctl start libvirtd" but setting it to 
autostart with "systemctl enable libvirtd" seems to have no effect. When 
I look at the status, it tells me that the service is "enabled" which 
means that it starts on bootup (well, that's what it means for any other 
service).


This is rather critical on this PC, as it has unattended restarts and 
the VPN/routing is done in one of the VMs (i.e. I can't get to it unless 
it auto-starts at least one VM).


Unfortunatley there is nothing appearing in the libvirtd log over a 
reboot to help diagnose.


Any suggestions?


Thank you

GC


[root@testhost ~]# systemctl status libvirtd
● libvirtd.service - Virtualization daemon
   Loaded: loaded (/usr/lib/systemd/system/libvirtd.service; enabled; 
vendor preset: enabled)

   Active: inactive (dead)
 Docs: man:libvirtd(8)
   http://libvirt.org




On 25/07/2017 1:20 AM, Jim Fehlig wrote:

On 07/23/2017 04:25 PM, G Crowe wrote:

Hi,
 I am trying to upgrade my Xen host (Dom0) and are having 
troubles getting it to work.


I think that it has booted into a kernel that supports Xen (running 
'xl info' does list some Xen capabilities), but I have three problems 
(that I have found so far).


Firstly, the "libvirtd" daemon doesn't start on bootup (and as a 
result all 'virsh' commands fail). It is set to auto-start (systemctl 
enable libvirtd), and can be manually started (systemctl start 
libvirtd), but it will not auto-start on reboot.


Secondly, Once I have manually started libvirtd, when I try to define 
a domain it gives me an error "could not find capabilities for 
arch=x86_64 domaintype=xen" and I haven't yet been able to define any 
domains. This domain type works fine on Fedora 21.


Thirdly, I am unable to convert to/from xml config format, it gives 
me the error "error: invalid argument: unsupported config type 
xen-xl" however the format "xen-xl" works fine on the Fedora 21 machine.


It sounds like the libvirt libxl driver is not loaded. Is the 
libvirt-daemon-driver-libxl package installed? If it's installed, 
enabling debug logging in libvirtd can provide hints why it is not 
loading


http://libvirt.org/logging.html

Regards,
Jim



I had these same issues when I tried to upgrade to Fedora 25 and 
assumed that something had been broken and so abandoned further 
attempts to upgrade, however since Fedora 26 is the same I am now 
assuming that I have stuffed something up myself (or missed something).


Fedora 21 uses kernel 3.19.3 and xen 4.4.1
Fedora 26 uses kernel 4.11.8 and xen 4.8.1

I have tried following the info on 
https://wiki.xen.org/wiki/Fedora_Host_Installation but it appears to 
be out of date now (I used this site when I started using Xen under 
Fedora 19, and when I upgraded to Fedora 21)


Does anyone have any suggestions? outputs from "xl info" and the 
domain config are below. I have also tried disabling SELinux, but it 
made no difference.



Thanks

GC

---
On the fedora 26 box.
# xl info
host   : family.mydomain.mytld
release: 4.11.8-300.fc26.x86_64
version: #1 SMP Thu Jun 29 20:09:48 UTC 2017
machine: x86_64
nr_cpus: 4
max_cpu_id : 3
nr_nodes   : 1
cores_per_socket   : 4
threads_per_core   : 1
cpu_mhz: 2712
hw_caps: 
b7ebfbff:77faf3bf:2c100800:0121:000f:009c67af::0100

virt_caps  : hvm hvm_directio
total_memory   : 8072
free_memory: 128
sharing_freed_memory   : 0
sharing_used_memory: 0
outstanding_claims : 0
free_cpus  : 0
xen_major  : 4
xen_minor  : 8
xen_extra  : .1
xen_version: 4.8.1
xen_caps   : xen-3.0-x86_64 xen-3.0-x86_32p 
hvm-3.0-x86_32 hvm-3.0-x86_32p hvm-3.0-x86_64

xen_scheduler  : credit
xen_pagesize   : 4096
platform_params: virt_start=0x8000
xen_changeset  :
xen_commandline: placeholder
cc_compiler: gcc (GCC) 7.0.1 20170421 (Red Hat 7.0.1-0.15)
cc_compile_by  : mockbuild
cc_compile_domain  : [unknown]
cc_compile_date: Wed May  3 21:23:49 UTC 2017
build_id   : 1c6e5a40165e05837303942b54757ae1f2d5033d
xend_config_format : 4

---
# cat vmtest.xml

   testVM
   2097152
   2097152
   1
   
 hvm
 /usr/lib/xen/boot/hvmloader
 
   
   
 
 
 
   
   
   destroy
   restart
   restart