Access to individual VMs

[Dennis Jacobfeuerborn]

Hi,
Is it possible to provide access to individual VMs using virsh or 
virt-manager? What I'm specifically trying to do is to give users the 
ability to shutdown/destroy/start their own virtual machines in case the VM 
hangs. Is this possible?

Regards,
   Dennis

[Don Dutile]

Dennis J. wrote:
>  Hi,
>  Is it possible to provide access to individual VMs using virsh or 
>  virt-manager? What I'm specifically trying to do is to give users the 
>  ability to shutdown/destroy/start their own virtual machines in case the VM 
>  hangs. Is this possible?
>  
>  Regards,
>     Dennis
>  _______________________________________________
>  virt mailing list
>  virt(a)lists.fedoraproject.org
>  https://admin.fedoraproject.org/mailman/listinfo/virt 
virsh <guest-name> shutdown 
     or
virsh <guest-name> destroy

after shutdown/destroy,
just do a
virsh <guest-name> start

This is assuming the guests are known to libvirt
(xml spec for guest resides in libvirt).

KVM guests? xen guest?

- Don

[Dennis Jacobfeuerborn]

On 02/18/2010 01:05 AM, Don Dutile wrote:
>  Dennis J. wrote:
> > Hi,
> > Is it possible to provide access to individual VMs using virsh or
> > virt-manager? What I'm specifically trying to do is to give users the
> > ability to shutdown/destroy/start their own virtual machines in case the VM
> > hangs. Is this possible?
> >
> > Regards,
> >     Dennis
> > _______________________________________________
> > virt mailing list
> > virt(a)lists.fedoraproject.org
> > https://admin.fedoraproject.org/mailman/listinfo/virt
>
>  virsh<guest-name>  shutdown
>        or
>  virsh<guest-name>  destroy
>
>  after shutdown/destroy,
>  just do a
>  virsh<guest-name>  start
>
>  This is assuming the guests are known to libvirt
>  (xml spec for guest resides in libvirt).
>
>  KVM guests? xen guest? 
Xen guests. The key though is that these users shouldn't have access to the 
host or the other users VMs. Basically I want to create a VM for user X and 
then the user should be able to login on that VM and be able to restart it 
if e.g. he locked himself out or the VM doesn't respond anymore.
 From what I understand you can provide access to the machines console 
using VNC/virt-viewer but AFAIK that doesn't provide you with the ability 
to reboot the VM if it crashed hard so it gets me only half the way.

Regards,
   Dennis

[Kenni Lund]

2010/2/18 Dennis J. <dennisml(a)conversis.de&gt;:
>  Xen guests. The key though is that these users shouldn't have
> access to the
>  host or the other users VMs. Basically I want to create a VM for user X and
>  then the user should be able to login on that VM and be able to restart it
>  if e.g. he locked himself out or the VM doesn't respond anymore.
>   From what I understand you can provide access to the machines console
>  using VNC/virt-viewer but AFAIK that doesn't provide you with the ability
>  to reboot the VM if it crashed hard so it gets me only half the way. 
If the user should be able to restart a crashed guest, you have to
design the system outside of the guest, as you've already described.
Perhaps create some small network service or a simple website, which
would take care of user authentication and only give the user the
ability to trigger predefined commands on your host.

Another, perhaps easier (depending on if you're into webdevelopment or
shell scripting) and more secure solution, could be to create another
Xen machine for "management", which only serves the purpose of being a
secure middleman between the host and all your guests. Setup SSHd on
the management server and disable all other services. Create an user
account for each of your guests and allow the users to login to the
management server with SSH. Create a shared reboot/shutdown script on
the management server, which all users are allowed to run and which
fx. sets a Reboot=1 Shutdown=1 flag in a text file, somewhere in the
users home directory. Now you just need to mount the all homedirs of
the management server on your Xen host via sshfs/fuse and have a
cronjob which once a minute checks the text-files of each user for new
reboot/shutdown/whatever requests. This would be as secure as it gets
and if you're into shell scripting, you can set it up in a few hours.

Best Regards
Kenni Lund

[Tom Horsley]

On Sat, 20 Feb 2010 14:51:42 +0100
Kenni Lund wrote:

>  If the user should be able to restart a crashed guest, you have to
>  design the system outside of the guest, as you've already described. 
Yep. At work we have a gazillion virtual machines for testing
on different linux distros, and I cobbled up a web cgi interface
folks who need a particular machine can use to reserve it and
have the cgi script run a virsh create command for them or
a script to shutdown the machine (which first tries clean shutdown
and if that doesn't work, does virsh destroy).

Something similar with the addition of some sort of authentication
layer could let users goto a web site and login to shutdown,
reboot, etc. their own machine. There must be canned examples
for web page login laying around on the web.

[Dennis Jacobfeuerborn]

On 02/20/2010 04:36 PM, Tom Horsley wrote:
>  On Sat, 20 Feb 2010 14:51:42 +0100
>  Kenni Lund wrote:
>
> > If the user should be able to restart a crashed guest, you have to
> > design the system outside of the guest, as you've already described.
>
>  Yep. At work we have a gazillion virtual machines for testing
>  on different linux distros, and I cobbled up a web cgi interface
>  folks who need a particular machine can use to reserve it and
>  have the cgi script run a virsh create command for them or
>  a script to shutdown the machine (which first tries clean shutdown
>  and if that doesn't work, does virsh destroy).
>
>  Something similar with the addition of some sort of authentication
>  layer could let users goto a web site and login to shutdown,
>  reboot, etc. their own machine. There must be canned examples
>  for web page login laying around on the web. 
That is my backup plan which apparently I need to go for.
The way I plan to do this is to create a central web interface and a 
management user on each host called "vmmanage" that can only execute a 
special script using the ssh command directive in the authorized_keys file. 
This script is then allowed to shutdown/destroy VMs using sudo. I still 
have to figure out some of the details but that's the basic idea.

Regards,
   Dennis