[virt-tools-list] Fwd: locked out after preseed install

Cole Robinson crobinso at redhat.com
Mon Apr 18 14:05:42 UTC 2016

On 04/18/2016 09:53 AM, Mario Gummies wrote:
> Hi Cole, hi all,
> 18.04.2016, 14:00, "Cole Robinson" <crobinso at redhat.com>:
>> On 04/15/2016 08:43 PM, Mario Gummies wrote:
>>>  Hi Cole, hi all,
>>>  could login via ssh from the host without preseeding. Thanks, now I know how
>>>  the result, I am after, looks like.
>>>  Well, then thinking about it. If my preseeding script seems the culprit:
>>>  1) Who should I ask? (guess the d-i, preseeding ppl)
>>>  2) My preseeding script to perform actually what? (Is there a requirements
>>>  interface standard between virt-install and d-i preseeding for the present use
>>>  case? The search for an existing, proper preseeding script gets easier knowing
>>>  to name.
>>>  3) what not to touch, because is is virt-install's job to setup the network?
>>>  4)
>>>  Is it what is called by libvirt virtual networking?
>>> http://wiki.libvirt.org/page/VirtualNetworking#The_default_configuration
>>>  5)
>>>  from my preseeding script
>>>  #in-target /bin/bash /root/postinst.sh #on the guest
>>>  One sees that one can trigger shell commands on the host. Is it not possible
>>>  to setup the missing network manual/scripted?
>>>  Really do not know, what would be best practice here or from here.
>> The preseeding script is entirely a debian/ubuntu installer convention. There
>> is no communication between virt-install and the preseed script. So I suggest
>> asking on ubuntu support channels
> Hi,
> Yes, I am already asking there. Well, virt-install and d-i preseeding might not communicate in a narrower sense, but it is true that the latter produces files which the former makes use of. To have that transaction functioning, the question for a format specification comes up.
> Question: Is there such a specification, about how the data transferred to lib-install should look like?
> Well, you might say: Just as the unpreseeded install and it might be the truth, but it is hard to understand for me and hard to believe, cause anybody who provides a new install to virt-install then runs into the same problem, preseeded or not.
> Question: Is it maybe the case, that there is such "convention" not explicit, but implicit in the code to be read?

All virt-install really does is set up the configuration file that describes
the VM's hardware. After that virt-install is completely out of the equation.

After the VM is started, the VM OS (ubuntu here) basically proceeds onward as
if it was on a real physical machine. There isn't any magic virt configuration
being passed back and forth here, the ubuntu installer is just detecting
hardware like disks and network through normal means and acting on it in the
same way as if it was a physical machine.

If a non-preseeded install, has working network at the end, but the same
virt-install command line _with_ a preseed file does _not_ work, then 99%
chance the issue is either with the preseed file or less likely the ubuntu

- Cole

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