Bug#766233: LXC breakage and workarounds when upgrading VMs to jessie

[Tomas Pospisek]

On Mon, 24 Nov 2014, Antonio Terceiro wrote:

> On Mon, Nov 24, 2014 at 07:48:28AM +0100, Tomas Pospisek wrote:
>> On Mon, 24 Nov 2014, Marco d'Itri wrote:
>>
>>> On Nov 24, Tomas Pospisek <tpo_deb at sourcepole.ch> wrote:
>>>
>>>> My first proposed text for the release-notes is below. Please let me
>>>> know if you prefer me to submit a proper patch against a SVN checkout of
>>>> ddp.
>>>
>>> Please also clarify that LXC containers *can* use systemd with no
>>> troubles if correctly configured.
>>
>> Could you please clarify what needs to be done to correctly configure a LXC
>> container?
>
> This:
> https://lists.linuxcontainers.org/pipermail/lxc-devel/2014-November/010900.html

I am aware of that, however:

1. As far as I understand this is a patch for a template used to create a
    new jessie LXC VM. Am I thus correct in assuming it's of no use for
    the "upgrade a LXC VM from wheezy to jessie"?

2. From the thread you link to it appears that it hasn't come to a
    resolution (i.e. if the patch gets included or further and what stuff
    is needed)?

> I am interacting with Daniel (Debian maintainer) to also get that into
> jessie.

Go Antonio, go! :-) !

However again, that'll be of no use when upgrading a wheezy lxc VM to 
jessie on a wheezy host?

>> * Is it sufficient to set: "lxc.autodev = 1" in /var/lib/lxc/myvm/config?
>
> Definitively not.

Marco d'Itri mentioned a "correctly configured VM", maybe we'll get some 
additional input from him, on what's required in the wheezy to jessie 
upgrade case.

>> * Does an upgrade also automatically switch to journald?
>>
>>   * In which case one *must* also set "lxc.kmsg=0" in
>>     "/var/lib/lxc/myvm/config" and remove "/dev/kmsg" inside the VM?
>>
>> * Is it possible to switch a system configured in such a way back and
>>   forth between systemd and sysvinit without having to change anything
>>   but the package selection? Or does that imply removing the configuration
>>   changes, i.e. removing "lxc.autodev = 1" and "lxc.kmsg=0" and recreating
>>   /dev/kmsg?
>>
>> * Is it possible to run the upgraded VM, that is correctly configured as
>>   you suggest on a normal wheezy host? Does the wheezy host need any
>>   special configuration?
>
> I don't have answers for these questions yet.

Thanks Antonio,
*t