April 2021 - Users - libvirt List Archives

how to use external snapshots with memory state
by Riccardo Ravaioli 12 Apr '21

12 Apr '21

Hi all, Best wishes for 2021! :) So I've been reading and playing around with live snapshots and still haven't figured out how to use an external memory snapshot. My goal is to take a disk+memory snapshot of a running VM and, if possible, save it in external files. As far as I understand, I can run: $ virsh snapshot-create $VM ... and that'll take an *internal* live snapshot of a given VM, consisting of its disks and memory state, which will be stored in the qcow2 disk(s) of the VM. In particular, the memory state will be stored in the first disk of the VM. I can then use the full range of snapshot commands available: revert, list, current, delete. Now, an external snapshot can be taken with: $ virsh snapshot-create-as --domain $VM mysnapshot --diskspec vda,file=/home/riccardo/disk_mysnapshot.qcow2,snapshot=external --memspec file=/home/riccardo/mem_mysnapshot.qcow2,snapshot=external ... with as many "--diskspec" as there are disks in the VM. I've read the virsh manual and the libvirt API documentation, but it's not clear to me what exactly I can do then with an external snapshot, in particular with the file containing the memory state. In articles from 7-8 years ago people state that external memory snapshots cannot be reverted... is it still the case today? If so, what's a typical usage for such files? If not with libvirt, is it possible to revert to an external memory + disk state in other ways, for instance through qemu commands? Thanks! Riccardo

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live migrate storage to different volume on the same host
by Jing-Wei Su 12 Apr '21

12 Apr '21

Hello experts, I would like to move the qcow2 disk images of a running VM to a different storage because of the maintenance of the underlying storage on the same host. I found the live migration is not allowable on the same host using virsh. Is there any suggestion or better practices for this? Thank you, Derek

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libvirt 7.2.0 domainbackup
by Thomas Stein 12 Apr '21

12 Apr '21

Hello one and all. Just wanted to check out the new feature domainbackup but having trouble to configure it. I thought I just have to put <domainbackup> <disks> <disk name='vda' type='file'> <target file='/var/lib/libvirt/jitsi'/> <driver type='raw'/> </disk> </disks> </domainbackup> at the top level of my domain xml file but that does not seem to work. I get: error: XML document failed to validate against schema: Unable to validate doc against /usr/share/libvirt/schemas/domain.rng Element domain has extra content: domainbackup Can someone please push me in the right direction? cheers, t.

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submitting a patch to fix documentation errors
by Tom Ammon 10 Apr '21

10 Apr '21

Hello, While using the libvirt application development guide for python ( https://libvirt.org/docs/libvirt-appdev-guide-python/en-US/html/index.html) I found a couple of errors in the example code that I'd like to fix. I've created a branch and committed the fixes locally, and I'm ready to push them. I plan to use git send-email to submit the patch. Which list should I use in the --to= ? Should it be libvirt-users(a)redhat.com? This is my first contribution to this project. I've read the best practices and contributing guidelines on libvirt.org, but if I make mistakes in the workflow I'd appreciate your help to correct them. Thanks! Tom -- ----------------------------------------------------------------------------- Tom Ammon M: (737) 400-9042 thomasammon(a)gmail.com -----------------------------------------------------------------------------

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Creating Virtual machine with .OVF format
by Ajay Kumar 09 Apr '21

09 Apr '21

Hello members, I would like to create virtual machine images with some pre-installed software in a .*OVF/OVA* format. So that I can use these* OVF *images/templates for any hypervisor to create a VM. Do you have any suggestions or some available web scripts/links to do this..? Thanks, Ajay

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XML for working mips64el guest
by Skyler Mäntysaari 08 Apr '21

08 Apr '21

Hi there, How do I get a working xml for mips64el guest when using virt-manager? The host system is running Ubuntu, but I believe that this is the right list for things relating to libvirt. It errors with: --------------------------------------------- Unable to complete install: 'this function is not supported by the connection driver: 'mips64el' architecture is not supported by CPU driver' Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/asyncjob.py", line 75, in cb_wrapper callback(asyncjob, *args, **kwargs) File "/usr/share/virt-manager/virtManager/createvm.py", line 2089, in _do_async_install guest.installer_instance.start_install(guest, meter=meter) File "/usr/share/virt-manager/virtinst/install/installer.py", line 542, in start_install domain = self._create_guest( File "/usr/share/virt-manager/virtinst/install/installer.py", line 491, in _create_guest domain = self.conn.createXML(install_xml or final_xml, 0) File "/usr/lib/python3/dist-packages/libvirt.py", line 4034, in createXML if ret is None:raise libvirtError('virDomainCreateXML() failed', conn=self) libvirt.libvirtError: this function is not supported by the connection driver: 'mips64el' architecture is not supported by CPU driver --------------------------------------------- This is what I'm trying to use: --------------------------------------------- <domain type="qemu"> <name>debian9-mips64el</name> <metadata> <libosinfo:libosinfo xmlns:libosinfo="http://libosinfo.org/xmlns/libvirt/domain/1.0"> <libosinfo:os id="http://debian.org/debian/9"/> </libosinfo:libosinfo> </metadata> <memory>1048576</memory> <currentMemory>1048576</currentMemory> <vcpu>2</vcpu> <os> <type arch="mips64el" machine="malta">hvm</type> <cmdline>nokaslr root=/dev/sda1 console=ttyS0</cmdline> <boot dev="hd"/> </os> <clock offset="utc"/> <devices> <emulator>/usr/bin/qemu-system-mips64el</emulator> <controller type="pci" index="0" model="pci-root"/> <disk type="file" device="disk"> <driver name="qemu" type="qcow2"/> <source file="/var/lib/libvirt/images/mip64el/stretch/disk.qcow2"/> <target dev="hda" bus="ide"/> </disk> <interface type="network"> <source network="default"/> <mac address="52:54:00:c5:63:f5"/> </interface> <console type="pty"/> </devices> </domain> ---------------------------------------------------------------------------------------------------------------

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Re: Regarding location of Libvirt library
by Andrea Bolognani 08 Apr '21

08 Apr '21

[once again, please keep replies on-list] On Wed, 2021-04-07 at 10:46 +0530, shafnamol N wrote: > > What does running > > > > $ ls /usr/lib/systemd/system/*virt* > > > > output? > > The output is as shown below: > > # ls /usr/lib/systemd/system/*virt* > /usr/lib/systemd/system/libvirtd-admin.socket /usr/lib/systemd/system/virtnodedevd.service > /usr/lib/systemd/system/libvirtd-ro.socket /usr/lib/systemd/system/virtnodedevd.socket > /usr/lib/systemd/system/libvirtd.service /usr/lib/systemd/system/virtnwfilterd-admin.socket > /usr/lib/systemd/system/libvirtd.service_backup /usr/lib/systemd/system/virtnwfilterd-ro.socket > /usr/lib/systemd/system/libvirtd.socket /usr/lib/systemd/system/virtnwfilterd.service > /usr/lib/systemd/system/libvirtd-tcp.socket /usr/lib/systemd/system/virtnwfilterd.socket > /usr/lib/systemd/system/libvirtd-tls.socket /usr/lib/systemd/system/virtproxyd-admin.socket > /usr/lib/systemd/system/libvirt-guests.service /usr/lib/systemd/system/virtproxyd-ro.socket > /usr/lib/systemd/system/virt-guest-shutdown.target /usr/lib/systemd/system/virtproxyd.service > /usr/lib/systemd/system/virtinterfaced-admin.socket /usr/lib/systemd/system/virtproxyd.socket > /usr/lib/systemd/system/virtinterfaced-ro.socket /usr/lib/systemd/system/virtproxyd-tcp.socket > /usr/lib/systemd/system/virtinterfaced.service /usr/lib/systemd/system/virtproxyd-tls.socket > /usr/lib/systemd/system/virtinterfaced.socket /usr/lib/systemd/system/virtqemud-admin.socket > /usr/lib/systemd/system/virtlockd-admin.socket /usr/lib/systemd/system/virtqemud-ro.socket > /usr/lib/systemd/system/virtlockd.service /usr/lib/systemd/system/virtqemud.service > /usr/lib/systemd/system/virtlockd.socket /usr/lib/systemd/system/virtqemud.socket > /usr/lib/systemd/system/virtlogd-admin.socket /usr/lib/systemd/system/virtsecretd-admin.socket > /usr/lib/systemd/system/virtlogd.service /usr/lib/systemd/system/virtsecretd-ro.socket > /usr/lib/systemd/system/virtlogd.socket /usr/lib/systemd/system/virtsecretd.service > /usr/lib/systemd/system/virtlxcd-admin.socket /usr/lib/systemd/system/virtsecretd.socket > /usr/lib/systemd/system/virtlxcd-ro.socket /usr/lib/systemd/system/virtstoraged-admin.socket > /usr/lib/systemd/system/virtlxcd.service /usr/lib/systemd/system/virtstoraged-ro.socket > /usr/lib/systemd/system/virtlxcd.socket /usr/lib/systemd/system/virtstoraged.service > /usr/lib/systemd/system/virtnetworkd-admin.socket /usr/lib/systemd/system/virtstoraged.socket > /usr/lib/systemd/system/virtnetworkd-ro.socket /usr/lib/systemd/system/virtvboxd-admin.socket > /usr/lib/systemd/system/virtnetworkd.service /usr/lib/systemd/system/virtvboxd-ro.socket > /usr/lib/systemd/system/virtnetworkd.socket /usr/lib/systemd/system/virtvboxd.service > /usr/lib/systemd/system/virtnodedevd-admin.socket /usr/lib/systemd/system/virtvboxd.socket > /usr/lib/systemd/system/virtnodedevd-ro.socket libvirtd.service_backup should not be there, but I don't think that's what causing your problem. I would still recommend deleting it just in case. > > What OS are you using? > > Centos 8 > > > What does the > > > > Miscellaneous > > ... > > Init script: XXX > > > > entry look like in the summary that's displayed when you run Meson? > > Miscellaneous > Init script : systemd These all look good, so I really have no idea what's going on. Hopefully someone else on the list will be able to help you! Good luck :) -- Andrea Bolognani / Red Hat / Virtualization

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Xen: libvirt.libvirtError: An error occurred, but the cause is unknown
by Mathieu Tarral 07 Apr '21

07 Apr '21

Hi, I'm facing a strange issue with libvirt and the Xen driver. Whenever I try to define or start a domain, I always get this error: "libvirt.libvirtError: An error occurred, but the cause is unknown" (in Python virt-manager interface) Which is not very helpful. Trying to use virsh directly leads to the same error message: virsh # start win10_xen error: Failed to start domain win10_xen error: An error occurred, but the cause is unknown I checked /var/log/libvirt/libxl/libxl-driver.log, but the log file is empty. However, using the xl toolstack directly to start a new domain works fine, so the issue doesn't seem to come from Xen. My environment: - Ubuntu 20.04 LTS - xen-hypervisor-4.11-amd64 (4.11.3+24-g14b62ab3e5-1ubuntu2) - libvirt0 (6.0.0-0ubuntu8.8) I really like libvirt and virt-manager to manage my VMs. Any clue how I could dig deeper and find the root cause ? Thanks.

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Live migration with change to setmaxmem
by Dariusz Smigiel 07 Apr '21

07 Apr '21

Hi Team, I need to migrate beefy instance between two different hosts which is running out of resources. I was wondering, if there is a way to change maximum memory value during live migration, without shutting down the instance. Thanks, Dariusz

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Re: Regarding location of Libvirt library
by Andrea Bolognani 06 Apr '21

06 Apr '21

[please keep replies on-list] On Mon, 2021-04-05 at 12:03 +0530, shafnamol N wrote: > Hi, > I have build libvirt in the following method: > $ meson build -Dsystem=true > $ ninja -C build > When i tried to get the information via > > $pkg-config --cflags --libs libvirt > > it doesnt show anything. > > But I tried > $ninja -C build install > > and then > $pkg-config --cflags --libs libvirt > It shows like: > libvirt-7.1.0]# pkg-config --cflags --libs libvirt > -lvirt This is expected: pkg-config can't find the libvirt.pc file until you've installed it :) > But the problem is when i tried to get the status of libvirt > > # systemctl status libvirtd > ● libvirtd.service > Loaded: not-found (Reason: Unit libvirtd.service not found.) > Active: failed (Result: exit-code) > > I tried with > # systemctl daemon-reload > But the problem persists.. > what will be the problem... What does running $ ls /usr/lib/systemd/system/*virt* output? What does the Miscellaneous ... Init script: XXX entry look like in the summary that's displayed when you run Meson? What OS are you using? -- Andrea Bolognani / Red Hat / Virtualization

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