Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Matt Riedemann
On 10/6/2017 1:10 PM, Mathieu Gagné wrote: I don't think there ever was a technical limitation to add support for it. See the review comments with the -1 votes on the patches I linked originally. There are valid technical reasons for the -1s on those, including on this one from Paul Murray

Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Ben Nemec
On 10/06/2017 12:22 PM, Matt Riedemann wrote: This came up in IRC discussion the other day, but we didn't dig into it much given we were all (2 of us) exhausted talking about rebuild. But we have had several bugs over the years where people expect the root disk to change to a newly supplied

Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Mathieu Gagné
> On Fri, Oct 6, 2017 at 2:02 PM, Chris Friesen > wrote: >> On 10/06/2017 11:32 AM, Mathieu Gagné wrote: >>> >>> Why not supporting this use case? >> >> >> I don't think anyone is suggesting we support do it, but nobody has stepped >> up to actually merge a change

Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Mathieu Gagné
I don't think there ever was a technical limitation to add support for it. I have nothing to back my claims but IIRC, it was more philosophical points against adding support for it. -- Mathieu On Fri, Oct 6, 2017 at 2:02 PM, Chris Friesen wrote: > On 10/06/2017

Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Sean Dague
On 10/06/2017 01:22 PM, Matt Riedemann wrote: > So with all of this in mind, should we at least consider, until at least > someone owns supporting this, that the API should fail with a 400 > response if you're trying to rebuild with a new image on a volume-backed > instance? That way it's a fast

Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Chris Friesen
On 10/06/2017 11:32 AM, Mathieu Gagné wrote: Why not supporting this use case? I don't think anyone is suggesting we support do it, but nobody has stepped up to actually merge a change that implements it. I think what Matt is suggesting is that we make it fail fast *now*, and if someone

Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread John Griffith
On Fri, Oct 6, 2017 at 11:22 AM, Matt Riedemann wrote: > This came up in IRC discussion the other day, but we didn't dig into it > much given we were all (2 of us) exhausted talking about rebuild. > > But we have had several bugs over the years where people expect the root >

Re: [openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Mathieu Gagné
Why not supporting this use case? Same reason as before: A user might wish to keep its IP addresses. The use cannot do the following to bypass the limitation: 1) stop instance 2) detach root volume 3) delete root volume 4) create new volume 5) attach as root 6) boot instance Last time I tried,

[openstack-dev] [nova] Should we make rebuild + new image on a volume-backed instance fail fast?

2017-10-06 Thread Matt Riedemann
This came up in IRC discussion the other day, but we didn't dig into it much given we were all (2 of us) exhausted talking about rebuild. But we have had several bugs over the years where people expect the root disk to change to a newly supplied image during rebuild even if the instance is