Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

fer , Richard Jones , qemu-block Cc: users Subject: Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack Better late than never - thank you all for the input, it was very useful! With the ability to measure the collapsed form of a volume chain

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Wed, Jul 11, 2018 at 11:30:19AM +0300, Arik Hadas wrote: > 4. Mount each reserved place for a disk as a loopback device and convert > the volume-chain directly to it [1] nbdkit tar plugin can overwrite a single file inside a tarball, all in userspace and non-root.

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

Better late than never - thank you all for the input, it was very useful! With the ability to measure the collapsed form of a volume chain in the qcow2 format, we managed to simplify and improve the process of creating an OVA significantly. What we do now is: 1. Measure the collapsed qcow2 volumes

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

Am 30.05.2018 um 18:14 hat Arik Hadas geschrieben: > On Wed, May 30, 2018 at 6:33 PM, Kevin Wolf wrote: > > I think the problem is that we're talking about two different things in > > one thread. If I understand correctly, what oVirt does today is: > > > > 1. qemu-img convert to create a

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Wed, May 30, 2018 at 6:33 PM, Kevin Wolf wrote: > Am 30.05.2018 um 17:05 hat Eric Blake geschrieben: > > If I understood the question, we start with a local: > > > > T (any format) <- S (qcow2) <- V (qcow2) > > > > and want to create a remote tar file: > > > > dest.tar == | header ... | qcow2

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

Am 30.05.2018 um 17:05 hat Eric Blake geschrieben: > If I understood the question, we start with a local: > > T (any format) <- S (qcow2) <- V (qcow2) > > and want to create a remote tar file: > > dest.tar == | header ... | qcow2 image | > > where we write a single collapsed view of the

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On 05/30/2018 09:16 AM, Kevin Wolf wrote: Am 30.05.2018 um 15:44 hat Eric Blake geschrieben: On 05/29/2018 04:18 PM, Nir Soffer wrote: You CAN get a logically collapsed view of storage (that is, what the guest would see), by using an NBD export of volume V. Reading from that volume will then

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

Am 30.05.2018 um 15:44 hat Eric Blake geschrieben: > On 05/29/2018 04:18 PM, Nir Soffer wrote: > > > You CAN get a logically collapsed view of storage (that is, what the > > > guest would see), by using an NBD export of volume V. Reading from that > > > volume will then pull sectors from

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On 05/29/2018 04:18 PM, Nir Soffer wrote: You CAN get a logically collapsed view of storage (that is, what the guest would see), by using an NBD export of volume V. Reading from that volume will then pull sectors from whichever portion of the chain you need. You can use either qemu-nbd (if no

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On 05/30/2018 07:35 AM, Nir Soffer wrote: This is not the flow we are looking for. We need a way to read qcow2 data from a pipe. Why? The qcow2 format inherently requires seeking (or a HUGE amount of free RAM) the moment you want to interpret the data as qcow2. It can't be piped when being

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Wed, May 30, 2018 at 03:35:11PM +0300, Nir Soffer wrote: > This is not the flow we are looking for. We need a way to read qcow2 data > from a pipe. The flow you asked for: > > > image in any format -> qemu-img -> [qcow2 byte stream] -> imageio http > > > server -> http client is exactly what

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Wed, May 30, 2018 at 11:58 AM Richard W.M. Jones wrote: > On Wed, May 30, 2018 at 12:11:21AM +0300, Nir Soffer wrote: > > Exporting images or ova files: > > > > image in any format -> qemu-img -> [qcow2 byte stream] -> imageio http > > server -> http client > > You can do this with nbdkit +

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Wed, May 30, 2018 at 12:35 AM Eric Blake wrote: > On 05/29/2018 04:11 PM, Nir Soffer wrote: > > >> I think real streaming is unlikely to happen because most image formats > >> that QEMU supports aren't made that way. If there is a compelling > >> reason, we can consider it, but it would work

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Wed, May 30, 2018 at 12:11:21AM +0300, Nir Soffer wrote: > Exporting images or ova files: > > image in any format -> qemu-img -> [qcow2 byte stream] -> imageio http > server -> http client You can do this with nbdkit + plugin, it's exactly what we do today for virt-v2v:

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On 05/29/2018 04:11 PM, Nir Soffer wrote: I think real streaming is unlikely to happen because most image formats that QEMU supports aren't made that way. If there is a compelling reason, we can consider it, but it would work only with very few target formats and as such would have to be

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Tue, May 29, 2018 at 10:43 PM Eric Blake wrote: > On 05/28/2018 05:27 AM, Arik Hadas wrote: > ... > > Few months ago people from the oVirt-storage team checked the qemu > toolset > > and replied that this capability is not yet provided, therefore we > > implemented the workaround described

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Mon, May 28, 2018 at 2:38 PM Kevin Wolf wrote: > Am 28.05.2018 um 12:27 hat Arik Hadas geschrieben: > > On Mon, May 28, 2018 at 11:25 AM, Kevin Wolf wrote: > > > > > [ Adding qemu-block ] > > > > > > Am 27.05.2018 um 10:36 hat Arik Hadas geschrieben: > > > > On Thu, May 24, 2018 at 6:13 PM,

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On 05/28/2018 05:27 AM, Arik Hadas wrote: [Answering before reading the entire thread; apologies if I'm repeating things, or if I have to chime in again at other spots] Let me demonstrate briefly the flow for OVA: Let's say that we have a VM that is based on a template and has one disk and

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

Am 29.05.2018 um 11:27 hat Richard W.M. Jones geschrieben: > On Mon, May 28, 2018 at 01:27:21PM +0300, Arik Hadas wrote: > > Let me demonstrate briefly the flow for OVA: > > Let's say that we have a VM that is based on a template and has one disk > > and one snapshot, so its volume-chain would be:

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Mon, May 28, 2018 at 01:27:21PM +0300, Arik Hadas wrote: > Let me demonstrate briefly the flow for OVA: > Let's say that we have a VM that is based on a template and has one disk > and one snapshot, so its volume-chain would be: > T -> S -> V > (V is the volume the VM writes to, S is the

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

On Mon, May 28, 2018 at 11:25 AM, Kevin Wolf wrote: > [ Adding qemu-block ] > > Am 27.05.2018 um 10:36 hat Arik Hadas geschrieben: > > On Thu, May 24, 2018 at 6:13 PM, Nir Soffer wrote: > > > > > On Thu, May 24, 2018 at 6:06 PM Vrgotic, Marko < >

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

Am 28.05.2018 um 12:27 hat Arik Hadas geschrieben: > On Mon, May 28, 2018 at 11:25 AM, Kevin Wolf wrote: > > > [ Adding qemu-block ] > > > > Am 27.05.2018 um 10:36 hat Arik Hadas geschrieben: > > > On Thu, May 24, 2018 at 6:13 PM, Nir Soffer wrote: > > > >

Re: [Qemu-block] [ovirt-users] Libvirt ERROR cannot access backing file after importing VM from OpenStack

[ Adding qemu-block ] Am 27.05.2018 um 10:36 hat Arik Hadas geschrieben: > On Thu, May 24, 2018 at 6:13 PM, Nir Soffer wrote: > > > On Thu, May 24, 2018 at 6:06 PM Vrgotic, Marko > > wrote: > > > >> Dear Nir, > >> > >> Thank you for quick reply. >