Xen & OpenNebula 5


Can I install OpenNebula 5.x to manage my Xen hosts ? In the documentation for v5.x, I don’t see any section for Xen hypervisor :frowning: http://docs.opennebula.org/5.0/deployment/node_installation/index.html

Can I use the same configuration in opennebula 4 and opennebula 5 to manage my Xen ?


Yes you can use the xen addon:

Support to the Xen hypervisor has not been removed from OpenNebula core,
but the driver was moved to the add-on catalog to ease the contributions
and support of the component from the comunity. The code is the same as the
one used in 4.x versions, so you can keep the same configuration. (Probably
if you are upgrading you don’t have to do anything, just keep using the
drivers and conf.)


Oki, cool thank you for the info.

I am having troubles using the xen drivers: i started to debug this issue already (removed error redirections in onehost_helper.rb and made rsync verbose)

rsync then told me that the driver never could be copied to the hosts because there are broken symlinks.

where would i get these missing files from? they are not in the xen-addon github repo.

oneadmin@poc1:~$ onehost sync --rsync poc3

  • Adding poc3 to upgrade
    [========================================] 1/1 poc3
    symlink has no referent: "/var/lib/one/remotes/xen/reconfigure"
    symlink has no referent: "/var/lib/one/remotes/xen/prereconfigure"
    symlink has no referent: "/var/lib/one/remotes/im/xen.d/collectd-client_control.sh"
    symlink has no referent: "/var/lib/one/remotes/im/xen.d/collectd-client.rb"
    rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1183) [sender=3.1.0]

Failed to update the following hosts:

  • poc3

alright, I guess I need those files:

do you provide them in one of the rpm packages?



tried to fix this by copying stuff from the one-5.0 git branch manually. here’s what i did:

cp -rv ~/git/one/src/im_mad/remotes/common.d /var/lib/one/remotes/im/xen.d/
cp -rv ~/git/one/src/tm_mad/common /var/lib/one/remotes/

vi /var/lib/one/remotes/im/xen-probes.d/poll.sh
# change path:
#../../vmm/xen/poll -t
../../xen/poll -t

chmod +x /var/lib/one/remotes/xen/poll

now this is the error I am getting in oned.log:

Mon Oct 17 17:06:13 2016 [Z0][InM][D]: Monitoring host poc3 (11)
Mon Oct 17 17:06:13 2016 [Z0][InM][I]: Command execution fail: 'if [ -x "/var/tmp/one/im/run_probes" ]; then /var/tmp/one/im/run_probes xen /var/lib/one//datastores 4124 20 11 poc3; else                              exit 42; fi'
Mon Oct 17 17:06:13 2016 [Z0][InM][I]: ../../xen/poll:26:in `require': no such file to load -- poll_common (LoadError)
Mon Oct 17 17:06:13 2016 [Z0][InM][I]: from ../../xen/poll:26
Mon Oct 17 17:06:13 2016 [Z0][InM][E]: Error executing poll.sh
Mon Oct 17 17:06:13 2016 [Z0][InM][E]: Error executing collectd-client_control.sh
Mon Oct 17 17:06:13 2016 [Z0][InM][I]: ExitCode: 1

Am I on the right path? Any suggestions would be appreciated :slight_smile:
Thanks and all the best

I am a step further I guess, I set the full path to poll_common in ./…/vmm/xen/poll:

#require "poll_common"
require '/var/lib/one/remotes/vmm/lib/poll_common.rb'

but now I am getting this error:

Tue Oct 18 11:35:45 2016 [Z0][ONE][E]: Error parsing host information: syntax error, unexpected VARIABLE, expecting EQUAL or EQUAL_EMPTY at line 1, columns 7:16. Monitoring information: 
Error executing sudo /usr/sbin/xentop -fbi2
MODELNAME="Intel(R) Xeon(R) CPU           X5550  @ 2.67GHz"

this command is working fine when i execute it on the “to be monitored” host:

sudo /usr/sbin/xentop -fbi2

my frontend is ubuntu14.04 and my xen hypervisor is centos6 and I use the debs and rpms ffrom the official 5.0.2 repos, could this have to do with the different paths? maybe the paths are different if you install ONE completely from git using the install script? maybe nobody ever tested the deb and rpm packages together with addon-xen? just guessing here…

we had this running with opennebula 4.14 before and it was running fine event tough frontend and HV were different OSes.

Anyone has actually running addon-xen without these problems? Should I open a bugreport for that? I will now have a look if this was reported already…

I realized that I am getting above mentioned monitoring errors, but the host is working and it is possible to run vms. i gave up searching why the monitoring operations fails sometimes.

one more thing i had to do on the frontend to get it working:

ln -s /var/lib/one/remotes/xen /var/lib/one/remotes/vmm/xen

and then of course:

onehost sync --rsync poc3

With all the information in this thread it should be possible to file a git commit and repair addon-xen so it works out of the box again. Unfortunately I don’t have the time at the moment…

What is actually the official way to report bugs? I think this: http://dev.opennebula.org/projects/opennebula

but with addons there is no official way to report bugs? correct? so the only way to fix stuff there is to make a PR on github?



Maybe it is a good idea to open a couple of issues in the Xen addon so we can tackle them from there:

Probably this issue is the same as:


Hi Ruben,
yes correct this is exactely this issue. I sent you a PR:


I fixed the paths, permissions and broken symlinks. the only thing that remains is the monitoring error as also stated in jeparre’s issue.

all the best

Ok let’s also discuss this in the forum and not only in the github issue, now that this should be actually fixed in the master branch:

I just installed everything from addon-xen master and also made sure that I do not have leftovers of the old broken and partly self-fixed addon. I am still getting this error. Not every time when it tries to monitor the host, but about every second time it throws this error !?! Still the host is shown as “On” in onehost show, but it is "enough of an error to trigger the HOST_HOOK and therefore certainly fences the host!!!

Wed Nov 9 10:18:23 2016 [Z0][ONE][E]: Error parsing host information: syntax error, unexpected VARIABLE, expecting EQUAL or EQUAL_EMPTY at line 1, columns 7:16. Monitoring information:
Error executing sudo /usr/sbin/xentop -fbi2

I also installed the mentionend one fix #139 (just quickly manually changed the line in vnm_mad/remotes/lib/vnmmad.rb)
I am using One 5.0.2 on Ubuntu 16.04

Which commit(s) of Laurent Grawets PR is actually dealing with this error? That would help me to further debug this issue.

Thank you very much!!
all the best from Vienna