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

[G Crowe]

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.

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out of date now (I used this site when I started using Xen under Fedora 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:2c100800:00000121:0000000f:009c67af:00000000:00000100
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=0xffff800000000000
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
<domain type='xen' id='21'>
   <name>testVM</name>
   <memory unit='KiB'>2097152</memory>
   <currentMemory unit='KiB'>2097152</currentMemory>
   <vcpu placement='static'>1</vcpu>
   <os>
     <type arch='x86_64' machine='xenfv'>hvm</type>
     <loader type='rom'>/usr/lib/xen/boot/hvmloader</loader>
     <boot dev='network'/>
   </os>
   <features>
     <acpi/>
     <apic/>
     <pae/>
   </features>
   <clock offset='variable' adjustment='0' basis='utc'/>
   <on_poweroff>destroy</on_poweroff>
   <on_reboot>restart</on_reboot>
   <on_crash>restart</on_crash>
   <devices>
     <interface type='bridge'>
       <mac address='02:02:00:03:00:00'/>
       <source bridge='enp1s0'/>
       <script path='vif-bridge'/>
     </interface>
     <serial type='pty'>
       <target port='0'/>
     </serial>
     <console type='pty'>
       <target type='serial' port='0'/>
     </console>
     <input type='mouse' bus='ps2'/>
     <input type='keyboard' bus='ps2'/>
     <graphics type='vnc' port='5901' autoport='no' 
listen='192.168.131.54'>
       <listen type='address' address='192.168.131.54'/>
     </graphics>
   </devices>
</domain>

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