search for: backing_fil

Hi list, suppose I have an immutable (ie: due to a read-only snapshot) backing file. After creating an overlay file with "qemu-img create -f qcow2 -o backing_file=/path/to/immutable/file.img current.qcow2", libvirt refuse to start the virtual machine and exits with an error stating "Could not open backing file /path/to/immutable/file.img: Permission denied". From my understanding, libvirtd is trying to change the owner/permissions/selinu...

...ot; -1 "backingfile:rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00\:\:cefc\:1]\:6789:auth_supported=none" "backingformat:raw" libguestfs: command: run: qemu-img libguestfs: command: run: \ create libguestfs: command: run: \ -f qcow2 libguestfs: command: run: \ -o backing_file=rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00\:\:cefc\:1]\:6789:auth_supported=none,backing_fmt=raw libguestfs: command: run: \ /root/libguestfs/tmp/libguestfs9gclsg/overlay1.qcow2 Formatting '/root/libguestfs/tmp/libguestfs9gclsg/overlay1.qcow2', fmt=qcow2 size=8589934592...

...The QEMU community still tends to discourage use of internal snapshots. There are not even any QMP monitor commands to use them - you are forced to use the legacy HMP interface to QEMU for mgmt. All of the workaround providing interesting block storage mgmt is focused on external snapshots (aka the backing_file option). There are some technical downsides to internal snapshots IIUC, such as inability to free the space used by the internal snapshot when it is deleted, loading/saving snapshots blocks execution of the guest OS, and probably more I've forgotten about. The only nice thing about internal s...

...d: run: \ create libguestfs: command: run: \ -f qcow2 libguestfs: command: run: \ -b /tmp/.guestfs-36/root.4124 libguestfs: command: run: \ -o backing_fmt=raw libguestfs: command: run: \ /tmp/libguestfsm4E1E4/snapshot1 Formatting '/tmp/libguestfsm4E1E4/snapshot1', fmt=qcow2 size=4294967296 backing_file='/tmp/.guestfs-36/root.4124' backing_fmt='raw' encryption=off cluster_size=65536 lazy_refcounts=off libguestfs: command: run: qemu-img libguestfs: command: run: \ create libguestfs: command: run: \ -f qcow2 libguestfs: command: run: \ -b /tmp/bV8yUVWwXU libguestfs: command: run: \...

...k_create "/tmp/libguestfsUIZbDK/overlay1.qcow2" "qcow2" -1 "backingfile:/home/peterd/TVE/wer.qcow2" "backingformat:qcow2" libguestfs: command: run: qemu-img libguestfs: command: run: \ create libguestfs: command: run: \ -f qcow2 libguestfs: command: run: \ -o backing_file=/home/peterd/TVE/wer.qcow2,backing_fmt=qcow2 libguestfs: command: run: \ /tmp/libguestfsUIZbDK/overlay1.qcow2 Formatting '/tmp/libguestfsUIZbDK/overlay1.qcow2', fmt=qcow2 size=107374182400 backing_file=/home/peterd/TVE/wer.qcow2 backing_fmt=qcow2 encryption=off cluster_size=65536 lazy_refc...

Hi There, I''ve been trying to get this to work for the last couple of days, but found no information on the internet that would help. Essentially, a tap-ctl opencommand with a qcow2 image does not work (error code 2) and produces the following line in syslog: tap-ctl: tap-err:tap_ctl_open: open failed, err -2 I have attached a shell script that reproduces the problem on my machine. The

..." -1 "backingfile:rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00::cefc:1]\:6789:auth_supported=none" "backingformat:raw" libguestfs: command: run: qemu-img libguestfs: command: run: \ create libguestfs: command: run: \ -f qcow2 libguestfs: command: run: \ -o backing_file=rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00::cefc:1]\:6789:auth_supported=none,backing_fmt=raw libguestfs: command: run: \ /tmp/libguestfs3pGMi6/overlay1.qcow2 qemu-img: /tmp/libguestfs3pGMi6/overlay1.qcow2: invalid conf option :cefc:1]:6789:auth_supported: No such file or directo...

...in /tmp/driver.sys win:/windows/system32/ copy-in /tmp/driver.inf win:/windows/system32/ -rm-rf win:/Temp/testprogs -mkdir win:/Temp copy-in /tmp/testprogs win:/Temp/ EOF ---------------------------------------------------------------------- I tested this by doing: $ qemu-img create -f qcow2 -o backing_file=/dev/vg_pin/Win7x32 win.qcow2 Formatting 'win.qcow2', fmt=qcow2 size=21474836480 backing_file='/dev/vg_pin/Win7x32' encryption=off cluster_size=65536 and creating some dummy driver.sys, driver.inf, testprogs directory (about 1 MB of data). I then tested the script above and it t...

...the same qemu-img command from collectd and it passes > though! Confusing... The log indicates something a bit strange is going on: > libguestfs: command: run: qemu-img > libguestfs: command: run: \ create > libguestfs: command: run: \ -f qcow2 > libguestfs: command: run: \ -o > backing_file=/home/peterd/TVE/wer.qcow2,backing_fmt=qcow2 > libguestfs: command: run: \ /tmp/libguestfsUIZbDK/overlay1.qcow2 > Formatting '/tmp/libguestfsUIZbDK/overlay1.qcow2', fmt=qcow2 > size=107374182400 backing_file=/home/peterd/TVE/wer.qcow2 backing_fmt=qcow2 > encryption=off cluster_...

..., take a screenshot, a core dump and a snapshot, then I resume the guest. Proof is that I can clearly analyse the memory core dump without any problem. Maybe I am breaking the disk's consistency once I extract the dump through the qemu-img command? The command is: qemu-img convert -f qcow2 -o backing_file=guest_disk.qcow2 -O qcow2 -s snapshot_n guest_disk.qcow2 new_disk_for_libguestfs.qcow2 Could it be that, as the backing file is pointing to the guest's disk which will evolve in time, when guestfs tries to read the data sees incosistencies? The guest_disk.qcow2 is a COW clone of a base_disk....

...gt;>>> "/tmp/libguestfs3pGMi6/overlay1.qcow2" "qcow2" -1 "backingfile:rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00::cefc:1]\:6789:auth_supported=none" >>>> "backingformat:raw" >>>> libguestfs: command: run: \ -o backing_file=rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00::cefc:1]\:6789:auth_supported=none,backing_fmt=raw >>>> libguestfs: command: run: \ /tmp/libguestfs3pGMi6/overlay1.qcow2 >>>> qemu-img: /tmp/libguestfs3pGMi6/overlay1.qcow2: invalid conf option >>>> :ce...

Hello, I am working on my PhD thesis and it would be really helpfull if someone could advise me, whether can Virsh create snapshots of VMs using copy-on-write. Thanks for reply. Juraj

...re it goes wrong: > >> "/tmp/libguestfs3pGMi6/overlay1.qcow2" "qcow2" -1 "backingfile:rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00::cefc:1]\:6789:auth_supported=none" >> "backingformat:raw" >> libguestfs: command: run: \ -o backing_file=rbd:images/CentOS-7-x86_64-GenericCloud-1901:mon_host=[fd00::cefc:1]\:6789:auth_supported=none,backing_fmt=raw >> libguestfs: command: run: \ /tmp/libguestfs3pGMi6/overlay1.qcow2 >> qemu-img: /tmp/libguestfs3pGMi6/overlay1.qcow2: invalid conf option >> :cefc:1]:6789:auth_supporte...

thanks . now i know qcow2 only store relative path. look at my error message, 6a3256bb-b247-4fb5-9f75-8ffa7151eeda i a symlink to a LV. it is the backing_file of several images(LV).. i have no idea of the reason of the error. # virt-win-reg 6a3256bb-b247-4fb5-9f75-8ffa7151eeda 'HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion' 'Productname' hivex: /tmp/libguestfsIdLWuF/0-software: trailing garbage at end of file (at 0x86e000, after 20...

...overlay1.qcow2 via qemu-img; note how backing file format is autodetected ("-f qcow2" regards the overlay file itself) [root@singularity images]# qemu-img create -b /var/lib/libvirt/images/base.qcow2 overlay1.qcow2 -f qcow2 Formatting 'overlay1.qcow2', fmt=qcow2 size=8589934592 backing_file=/var/lib/libvirt/images/base.qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 [root@singularity images]# qemu-img info overlay1.qcow2 image: overlay1.qcow2 file format: qcow2 virtual size: 8.0G (8589934592 bytes) disk size: 17K cluster_size: 65536 backing file: /var/lib/libvirt/images...

I have not found support in libvirt (nor virsh) for doing the equivalent of "qemu-img rebase ....". The use case: You have copied a qcow2 stack and the new files have different names or reside in a different directory. Therefore you need to change the backing file. Is there a way to do this? Is this a planned addition to libvirt? Harald -------------- next part

...it passes > > though! Confusing... > > The log indicates something a bit strange is going on: > > > libguestfs: command: run: qemu-img > > libguestfs: command: run: \ create > > libguestfs: command: run: \ -f qcow2 > > libguestfs: command: run: \ -o > > backing_file=/home/peterd/TVE/wer.qcow2,backing_fmt=qcow2 > > libguestfs: command: run: \ /tmp/libguestfsUIZbDK/overlay1.qcow2 > > Formatting '/tmp/libguestfsUIZbDK/overlay1.qcow2', fmt=qcow2 > > size=107374182400 backing_file=/home/peterd/TVE/wer.qcow2 > backing_fmt=qcow2 > &gt...

..."/tmp/libguestfs8F29Zb/overlay1.qcow2" "qcow2" -1 "backingfile:/var/tmp/.guestfs-0/appliance.d/root" "backingformat:raw" libguestfs: command: run: qemu-img libguestfs: command: run: \ create libguestfs: command: run: \ -f qcow2 libguestfs: command: run: \ -o backing_file=/var/tmp/.guestfs-0/appliance.d/root,backing_fmt=raw libguestfs: command: run: \ /tmp/libguestfs8F29Zb/overlay1.qcow2 Formatting '/tmp/libguestfs8F29Zb/overlay1.qcow2', fmt=qcow2 size=4294967296 backing_file='/var/tmp/.guestfs-0/appliance.d/root' backing_fmt='raw' encryptio...

...ml/qemu-devel/2013-06/msg04229.html [**] NBD over TCP: (1) Run an NBD server locally: $ qemu-nbd -f qcow2 -p10809 \ /var/lib/libvirt/images/cirros-0.3.3-x86_64-disk.img -t (2) Create an overlay using the NBD server as backing file: $ qemu-img create -f qcow2 -F raw \ -o backing_file=nbd://localhost nbd-overlay1.qcow2 (3) Optionally, boot the overlay w/ a minimal CLI. $ qemu-system-x86_64 \ -nographic \ -nodefconfig \ -nodefaults \ -m 2048 \...

On Wed, Mar 25, 2015 at 07:38:03PM +0100, Kashyap Chamarthy wrote: > On Mon, Mar 23, 2015 at 10:43:30PM +0000, Richard W.M. Jones wrote: > > [. . .] > > > > This makes a copy of the whole disk image. It's also not a consistent > > > (point in time) copy. > > > > Oh I see that you're copying the _snapshot_ that you created with > >