snapshot-create error: this function is not supported by the connection driver: virDomainSnapsho

English Virtualization
#1

Opensuse 15.2 with xen kernel. Dom0 running. A vm created and paused (webserver). I try to create a snapshot of the vm with virsh but it fails


virsh # list 
 Id   Name        State 
--------------------------- 
 0    Domain-0    running 
 3    webserver   paused 


virsh # snapshot-create webserver 
error: this function is not supported by the connection driver: virDomainSnapshotCreateXML 

virsh #

I think the syntax of the virsh command is correct, so I guess something is broken in the installation, but I can’t find what. I find some things like this but no solution.

Any clues?

best regards

#2

That doesn’t look right. I have a feeling that your “#” in the command “virsh # snapshot-create webserver” shouldn’t be there. But then again, what do I know.

#3

You mean I should not be doing it as root?

I have created it as root, but remotely using virt-manager, but as I can’t find the ways to do a snapshot with virt-manager I have seen that virsh seems much more powerful.

The thing is that other comands work fine


virsh # list 
 Id   Name        State 
--------------------------- 
 0    Domain-0    running 
 3    webserver   paused 

virsh # resume webserver 
Domain webserver resumed 

virsh # list 
 Id   Name        State 
--------------------------- 
 0    Domain-0    running 
 3    webserver   running 

virsh #
#4

This may be completely unrelated to your issue, but there’s no way to know for sure. A couple days ago I installed a bunch of qemu updates, which resulted in a non-functional virt-manager. When attempting to connect via the GUI, it just sat there forever, no password prompt, nothing. I don’t know if it was a hiccup in the download or a bad update that I timed perfectly or what. I rolled the system back with snapper, waited a couple days and ran the update again. Everything seems to be working this time. If you recently updated the qemu packages, that may be a factor here. It seemed to be in my case.

The command you ran to create the snapshot is correct. I would guess there was a problem with the installation or recent update.

#5 


**vm2:~ #** LANG=C zypper up 
Loading repository data... 
Reading installed packages... 

The following 2 NEW packages are going to be installed: 
  grub2-x86_64-efi kernel-default-5.3.18-lp152.72.1 

The following 52 packages are going to be upgraded: 
  e2fsprogs grub2 grub2-i386-pc grub2-snapper-plugin grub2-systemd-sleep-plugin grub2-x86_64-xen gzip irqbalance libcom_err2 libext2fs2 libgpgme11 libldap-2_4-2 libldap-data 
  libmpfr6 libnuma1 libprocps7 libruby2_5-2_5 libsystemd0 libudev1 mdadm numactl openldap2-client procps qemu qemu-block-curl qemu-block-rbd qemu-ipxe qemu-ksm qemu-microvm 
  qemu-seabios qemu-sgabios qemu-tools qemu-ui-curses qemu-ui-gtk qemu-ui-sdl qemu-ui-spice-app qemu-vgabios qemu-x86 rsyslog ruby2.5 ruby2.5-stdlib shim sudo systemd 
  systemd-bash-completion systemd-container systemd-presets-common-SUSE systemd-sysvinit tcsh tcsh-lang udev yast2-security 

The following 2 packages require a system reboot: 
  kernel-default-5.3.18-lp152.72.1 systemd 

52 packages to upgrade, 2 new. 
Overall download size: 105.9 MiB. Already cached: 0 B. After the operation, additional 388.4 MiB will be used. 

    Note: System reboot required. 
**Continue? [y/n/v/...? shows all options] (y):**

Yes, it update some qemu stuff
But it did not solve the error.


**vm2:~ #** LANG=C virsh 
Welcome to virsh, the virtualization interactive terminal. 

Type:  'help' for help with commands 
       'quit' to quit 

virsh # start webserver 
Domain webserver started 

virsh # list 
 Id   Name        State 
--------------------------- 
 0    Domain-0    running 
 2    webserver   running 

virsh # snapshot-create webserver 
error: this function is not supported by the connection driver: virDomainSnapshotCreateXML 

virsh #
#6

No, I mean it probably should be written this way: “# virsh snapshot-create webserver”. “virsh” IS the command that you write AS root. Hoping that I made sense. But, like I said, what do I know.

#7

yes, you can write virsh <someting> but yo can also type virsh without parameters and you enter in a virsh shell

virsh #

and the when you type a command it appears to the right of #

#8

Are you able to create a snapshot of Domain-0? If you can, then there must be a configuration issue with the webserver domain. I have not run into this problem myself, so I do not have any definitive solutions for you. If you are unable to create a snapshot of either domain, then it might be a problem with the installation.

#9

No, same error

vm2:~ # LANG=C virsh
Welcome to virsh, the virtualization interactive terminal.

Type:  'help' for help with commands
       'quit' to quit

virsh # list
 Id   Name        State
---------------------------
 0    Domain-0    running
 2    webserver   running

virsh # snapshot-create Domain-0
error: this function is not supported by the connection driver: virDomainSnapshotCreateXML

virsh #
#10

For all I can tell, Xen libvirt driver does not implement snapshots.

#11

That must be the problem… all info I find about libvirt snapshots is about KVM

#12

Cleaning up old Forum threads while I’ve been gone,

Yes, Xen does not support snapshots, is in the openSUSE Virtualization documentation

https://doc.opensuse.org/documentation/leap/virtualization/html/book-virt/cha-libvirt-managing.html#sec-libvirt-managing-snapshots

TSU