Timo Benk
2006-Oct-12 08:42 UTC
[Xen-devel] 3.0.3rc3 qcow image created with qemu-img not usable?
Hi, i am new to the qcow image format, so please forgive me if the following is just totally stupid:-) I try to use a qcow formatted image in Xen created by qemu-img. # qemu-img create -f qcow /tmp/test.img 1G Then i try to attach that image to Domain-0. # xm block-attach Domain-0 tap:qcow:/tmp/test.img /dev/xvda1 w 0 No error message so far, but ... # mount /dev/xvda1 /mnt mount: special device /dev/xvda1 does not exist # xm block-list Domain-0 Vdev BE handle state evt-ch ring-ref BE-path 51714 0 0 3 23 8 /local/domain/0/backend/tap/0/51714 # xm block-detach Domain-0 /dev/xvda1 # xm block-list Domain-0 Vdev BE handle state evt-ch ring-ref BE-path 51714 0 0 3 23 8 /local/domain/0/backend/tap/0/51714 qcow images created with qcow-create are working without any problems. And a few additional questions i have: - Is qcow encryption supported? - is qcow compression supported? Greetings, -timo -- Timo Benk - Jabber ID: fry@jabber.org - ICQ ID: #241877854 PGP Public Key: http://m28s01.vlinux.de/timo_benk_gpg_key.asc _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Anthony Liguori
2006-Oct-12 13:02 UTC
[Xen-devel] Re: 3.0.3rc3 qcow image created with qemu-img not usable?
You cannot attach block devices to Domain-0. Furthermore, you cannot attach non-raw file-based block devices to paravirtual domains. Regards, Anthony Liugoir Timo Benk wrote:> Hi, > > i am new to the qcow image format, so please forgive me if the following > is just totally stupid:-) > > I try to use a qcow formatted image in Xen created by qemu-img. > > # qemu-img create -f qcow /tmp/test.img 1G > > Then i try to attach that image to Domain-0. > > # xm block-attach Domain-0 tap:qcow:/tmp/test.img /dev/xvda1 w 0 > > No error message so far, but ... > > # mount /dev/xvda1 /mnt > mount: special device /dev/xvda1 does not exist > > # xm block-list Domain-0 > Vdev BE handle state evt-ch ring-ref BE-path > 51714 0 0 3 23 8 > /local/domain/0/backend/tap/0/51714 > > # xm block-detach Domain-0 /dev/xvda1 > > # xm block-list Domain-0 > Vdev BE handle state evt-ch ring-ref BE-path > 51714 0 0 3 23 8 > /local/domain/0/backend/tap/0/51714 > > qcow images created with qcow-create are working without any problems. > > And a few additional questions i have: > > - Is qcow encryption supported? > - is qcow compression supported? > > Greetings, > -timo >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Timo Benk
2006-Oct-12 13:17 UTC
Re: [Xen-devel] Re: 3.0.3rc3 qcow image created with qemu-img not usable?
Anthony Liguori wrote:> You cannot attach block devices to Domain-0. Furthermore, you cannot > attach non-raw file-based block devices to paravirtual domains.I can and Xen can do so too :-) I just followed the description in [1]. And the point is as i have explained: it works with qcow-create created images but not with qemu-img created images. I do not know if that is by design or a bug. IMHO the Xen qcow format is compatible with qemu so it should work. [1]http://xenbits.xensource.com/xen-3.0.3-testing.hg/tools/blktap/README Greetings, -timo -- Timo Benk - Jabber ID: fry@jabber.org - ICQ ID: #241877854 PGP Public Key: http://m28s01.vlinux.de/timo_benk_gpg_key.asc _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Anthony Liguori
2006-Oct-12 13:59 UTC
Re: [Xen-devel] Re: 3.0.3rc3 qcow image created with qemu-img not usable?
Timo Benk wrote:> Anthony Liguori wrote: > >> You cannot attach block devices to Domain-0. Furthermore, you cannot >> attach non-raw file-based block devices to paravirtual domains. >> > I can and Xen can do so too :-) >Sorry, I forgot about blktap... blktap requires a certain cluster size for qcow images IIRC. That''s probably why qemu-img doesn''t work. Regards, Anthony Liguori> I just followed the description in [1]. > > And the point is as i have explained: it works with qcow-create created > images but not with qemu-img created images. > > I do not know if that is by design or a bug. > > IMHO the Xen qcow format is compatible with qemu so it should work. > > [1]http://xenbits.xensource.com/xen-3.0.3-testing.hg/tools/blktap/README > > Greetings, > -timo >_______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel