"ALERT! /dev/disk/by-uuid/X-X-X-X does not exist." when booting Ubuntu with Xen

[Mikael_Niemel]

Yeah, now it seems to work. But one more unrelated question, is there some way to specify Xen guests to be run on 32-bit only mode in the config file? I didn't find such option with quick googling.

[MAFoElffen]

Xen and KVM both use QEMU and Libvirt. So, since they both use the same QEMU and virstet, a lot of the file locations and their format is the same. The terminology for them defers between the 2. ....and Xen uses another toolset on top of wqemu and virsh.

The older version of Xen used the individual DomU conf files in /etc/xen. now xm was replaced with xl ... and honestly, I'm still getting used to that and trying to find the specific differences and how to work with it (specific behind the scene details).

Xen does PV (para-virtualized machine) and HVM (fully virtualized machine)... By the older xml format, there was:

...
  <os>
    <type arch='x86_64' machine='xenpv'>linux</type>
  </os>
...

where if you wanted to run only a 32bit guest, you changed that section to

...
  <os>
    <type arch='i686' machine='xenpv'>linux</type>
  </os>
...

/etc/xen/xl.conf iis the default conf file. It is in a xen formal, rather that the xml format that KVM uses.

in the xen for, it is "different." Xen is now shielded on where and how the DomU config files. I hear that the individual guests may now be stored in a db, instead of individually, as before... but not confirmed yet, and I'm still looking fr them on my own to see just how it is physically (real world, behind the scenes).

But if I start up a DomU domain and do

sudo xl list -lV Domain_Name

it lists out the config for that domain in it's own kind of format.

But if I do

sudo virsh edit Domain_Name

It starts an editor, to edit the config in XML format. xl also has an option to convert a config from xl format to xml // and xml to xl.

I'm thinking that if I edit a domain in xml... htne dump the converted xml to xl format... then I can see what it actually changes in the xl format.

The file /etc/xen/xl.conf is the default configuration file. So if we found what that change is, and applied that change to that file...

But I can't try that until Monday. Almost out the door to a funeral and celebration of life for my belated brother-in-law.

[Mikael_Niemel]

My condolences. And no need to hurry, this is just a hobby project for me..


Anyways, I have been using /etc/xen/*.cfg config files to setup DomU, but I haven't found any options for that. Adding line 'arch = "i686"' didn't do anything. I haven't seen that xml format anywhere, either, and

sudo xl list -lV Domain_Name

Outputs the data in JSON format, and there's no arch option visible.