Unable to create a snapshot

Product Support
1

7.0.0version

When I was creating a snapshot, an error was prompted:

Wed Jul 30 14:51:30 2025 [Z0][VM][I]: New LCM state is HOTPLUG_SNAPSHOT
Wed Jul 30 14:51:31 2025 [Z0][VMM][I]: Command execution failed (exit code: 255): 'if [ -x "/var/tmp/one/vmm/kvm/snapshot_create" ]; then /var/tmp/one/vmm/kvm/snapshot_create 3cb71ec5-3d1e-42ff-b471-2250351d2cc9 0 6 10.9.200.6; else                              exit 42; fi'
Wed Jul 30 14:51:31 2025 [Z0][VMM][I]: error: unsupported configuration: internal snapshot for disk sda unsupported for storage type raw
Wed Jul 30 14:51:31 2025 [Z0][VMM][I]: Could not create snapshot  for domain 3cb71ec5-3d1e-42ff-b471-2250351d2cc9.
Wed Jul 30 14:51:31 2025 [Z0][VMM][E]: SNAPSHOTCREATE: error: unsupported configuration: internal snapshot for disk sda unsupported for storage type rawCould not create snapshot  for domain 3cb71ec5-3d1e-42ff-b471-2250351d2cc9.

I understand the error message that snapshots cannot be created for the raw format. However, I don’t know how to adjust the parameters. I’ve tried many methods (referring to “LVM Thin Internals LVM”) but still haven’t achieved the snapshot function. I need help.

The IMAGE DS storage is ultimately stored on the NFS node. The NFS shared disk is mounted to the manager1 node in the form of network mounting.

192.168.100.1:/data/nfs_share  5.2T  4.4G  5.2T   1% /var/lib/one/datastores
root@manager1:/opt/tp# cat ds_image_new.conf 
NAME = lvm_image
DS_MAD = fs
TM_MAD = fs_lvm_ssh
DISK_TYPE = "BLOCK"
TYPE = IMAGE_DS
LVM_THIN_ENABLE = YES
PERSISTENT_SNAPSHOTS = YES
SAFE_DIRS="/var/tmp /tmp /var/lib/one"

The SYSTEM DS uses LVM.

root@manager1:/opt/tp# vgs
  VG         #PV #LV #SN Attr   VSize   VFree 
  vg-one-103   1   2   0 wz--n- <30.00t 29.96t
root@manager1:/opt/tp# cat ds_system.conf 
NAME   = system_ds
TM_MAD = fs_lvm_ssh
TYPE   = SYSTEM_DS
DISK_TYPE = BLOCK
LVM_THIN_ENABLE = YES
PERSISTENT_SNAPSHOTS = YES # This setting has no effect. It still shows "NO" in the system.

Regards.

2

AFAIK the VM Snapshots interface use libvirt functionality which works with qcow2 files only…

3

Thank you for your explanation. I can understand what you said. My original image file is in qcow format, but the image and virtual machine disk created through LVM will default to raw format. How should I modify it?

Should I let it default to raw format and adjust the parameters to meet LVM Thin for achieving the snapshot function?

I don’t know which solution is more suitable and how to adjust the parameters and choose the solution.

4

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.