[Pkg-xen-devel] xen-api: xcp-xapi.init conflicts with xend

[Thomas Goirand]

On 12/22/2011 06:39 PM, Mike McClurg wrote:
> On Thu, Dec 22, 2011 at 4:27 AM, Thomas Goirand <thomas at goirand.fr> wrote:
>> On 12/22/2011 05:13 AM, Jonathan Ludlam wrote:
>>> I think that the mechanism to disable xend via /etc/default/xen hasn't
>>> been uploaded yet;
>>
>> It has! That's how I switch from xm to xl on my SID box.
>>
>>> it's in xen-utils-common_4.1.2-2.
>>
>> 4.1.2-1 has it too.
>>
> 
> We're developing on Ubuntu right now, and it looks like
> xen-utils-common-4.1.0~rc6-1ubuntu1 is the latest we have. I'd like
> our solution to work on both systems, so that we have to make minimal
> changes between the debian and ubuntu packages.

Why don't you ask that Ubuntu takes the current Xen packages in SID? As
far as I can tell, they work pretty well!

> I had considered
> checking for the pid file, but wasn't sure if that was the best way to
> do it. If you think it is, I'll modify that pull request.

I'm unsure if it is. But I'm quite sure that reading /etc/default/xen
makes sense, because that's the switch that disables xend and xm in
favor of xl on the Debian package. Which is why I was proposing to ask a
question in a nice debian blue screen (eg: debconf)!

> After doing some checking, though, I'm not sure that completely
> disabling xend is the right thing to do. I took a look at the xend
> init script, and it does more than start xend.

If you put "xl" in /etc/default/xen, then it wont start xend.

> It's also responsible
> for starting xenstored and xenconsoled, which we need.

Correct, which is why I believe it should be considered to use debconf.
Note that with "preseding" you can also script the use of one or another
choice, and that's the only thing which is supported to do so in Debian.

I'll work on this if nobody oppose to it.

> It seems like
> the best thing to do might actually be to have xcp-xapi.init shut down
> xend

No. I believe it's an admin's decision to use xm or xl. Don't force
anyone to your own choices. I might want to install and use xcp-xapi for
a while, then edit the TOOLSTACK variable in /etc/default/xen, reboot,
and use xend, if I want to. I wouldn't like xcp-xapi init.d script to
make the nice joke of killing xend when I've decided to use it.

Just printing a nice message explaining to the server admin where's the
/etc/default/xen TOOLSTACK variable is the only thing that I would
recommend.

> instead of failing to run if xend.pid is present. The other
> option is to reimplement xend.init's functionality in xcp-xapi.init,
> but I'm not sure we want that responsibility.

Xend init script is already in the xen package, why would you do that?

Cheers,

Thomas