# VM snapshots failing on ON 7.0.1 on SAN lvols **URL:** \ **Category:** Operations\ **Created:** [February 25, 2026, 7:37pm UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406 "2026-02-25T19:37:29Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![pnwjoe](https://avatars.discourse-cdn.com/v4/letter/p/2acd7d/32.png) [@pnwjoe](https://forum.opennebula.io/u/pnwjoe)\ **Post date:** [February 25, 2026, 7:37pm UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/1 "2026-02-25T19:37:29Z")
VM snapshots failing: LVM\_THIN\_ENABLE=YES is set on both image and system datastores, but VMs are provisioned with standard LVs, not thin LVs. The fs\_lvm/clone script has no thin logic and snap\_create just returns ‘Operation not supported’ * * * **Versions of the related components and OS (frontend, hypervisors, VMs):OpenNebula 7.0.1 Frontend:** opennebula-common-onecfg-7.0.1-1.el9.noarch opennebula-common-7.0.1-1.el9.noarch opennebula-rubygems-7.0.1-1.el9.x86\_64 opennebula-libs-7.0.1-1.el9.noarch opennebula-guacd-7.0.1-1.2.0+1.el9.x86\_64 opennebula-tools-7.0.1-1.el9.noarch opennebula-migration-7.0.1-1.el9.noarch opennebula-7.0.1-1.el9.x86\_64 opennebula-fireedge-7.0.1-1.el9.x86\_64 opennebula-flow-7.0.1-1.el9.noarch opennebula-gate-7.0.1-1.el9.noarch KVM nodes:\*\* “\*\*opennebula-common-7.0.1-1.el9.noarch” RHEL 9.7 VM== RHEL 8.10 **Steps to reproduce: try to create a snapshot via command line. Either when vm running or powered off** \*\*Current results:\*\*Tue Feb 24 14:35:53 2026 [Z0][VM][I]: New LCM state is RUNNING Tue Feb 24 14:47:05 2026 [Z0][VM][I]: New state is ACTIVE Tue Feb 24 14:47:05 2026 [Z0][VM][I]: New LCM state is DISK\_SNAPSHOT Tue Feb 24 14:47:05 2026 [Z0][VMM][E]: DISKSNAPSHOTCREATE: Cannot perform a live DISKSNAPSHOTCREATE operation Tue Feb 24 14:47:05 2026 [Z0][VM][I]: New LCM state is RUNNING Tue Feb 24 14:47:05 2026 [Z0][LCM][E]: Could not take disk snapshot. Tue Feb 24 14:47:11 2026 [Z0][VMM][I]: Ignoring VM state update Tue Feb 24 14:49:54 2026 [Z0][VM][I]: New LCM state is SHUTDOWN\_POWEROFF Tue Feb 24 14:50:04 2026 [Z0][VMM][I]: ExitCode: 0 Tue Feb 24 14:50:04 2026 [Z0][VMM][I]: Successfully execute virtualization driver operation: shutdown. Tue Feb 24 14:50:04 2026 [Z0][VMM][I]: clean: Executed “sudo -n ovs-ofctl del-flows ovsbr0 in\_port=27”. Tue Feb 24 14:50:04 2026 [Z0][VMM][I]: clean: Executed “sudo -n ovs-vsctl --if-exists del-port ovsbr0 one-15-0”. Tue Feb 24 14:50:04 2026 [Z0][VMM][I]: ExitCode: 0 Tue Feb 24 14:50:04 2026 [Z0][VMM][I]: Successfully execute network driver operation: clean. Tue Feb 24 14:50:04 2026 [Z0][VM][I]: New state is POWEROFF Tue Feb 24 14:50:04 2026 [Z0][VM][I]: New LCM state is LCM\_INIT Tue Feb 24 14:50:14 2026 [Z0][VMM][I]: Ignoring VM state update Tue Feb 24 14:50:30 2026 [Z0][VMM][I]: Ignoring VM state update Tue Feb 24 14:51:36 2026 [Z0][VM][I]: New state is ACTIVE Tue Feb 24 14:51:36 2026 [Z0][VM][I]: New LCM state is DISK\_SNAPSHOT\_POWEROFF Tue Feb 24 14:51:36 2026 [Z0][TrM][I]: Command execution failed (exit code: 1): /var/lib/one/remotes/tm/fs\_lvm/snap\_create onenode03:/var/lib/one//datastores/102/15/disk.0 1 15 101 Tue Feb 24 14:51:36 2026 [Z0][TrM][I]: snap\_create: Operation not supported Tue Feb 24 14:51:36 2026 [Z0][TrM][E]: Error executing image transfer script: snap\_create: Operation not supported Tue Feb 24 14:51:36 2026 [Z0][LCM][E]: Could not take disk snapshot. **Expected results:** ---
**Author:** ![FrancJP](https://yyz1.discourse-cdn.com/flex031/user_avatar/forum.opennebula.io/francjp/32/7690_2.png) [@FrancJP](https://forum.opennebula.io/u/FrancJP)\ **Post date:** [February 27, 2026, 12:53pm UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/2 "2026-02-27T12:53:30Z")
Hello @pnwjoe, and welcome to this forum. What you’re seeing with snapshots failing on SAN LVols in OpenNebula 7.0.1 is consistent with current limitations in the snapshot implementation when using the fs\_lvm driver and standard LVM logical volumes. From the logs you shared, the VMs are being created on regular LVs (not thin-provisioned) even though you have `LVM_THIN_ENABLE=YES`. Because the fs\_lvm snapshot scripts don’t have logic for handling snapshots on non-thin LVs, the snap\_create command returns “_Operation not supported_.” That’s why the VM transitions to the `DISK_SNAPSHOT` or `DISK_SNAPSHOT_POWEROFF` state and then fails with that message. You can find more info in the documentation: - [SAN Storage Configuration (LVM drivers)](https://docs.opennebula.io/7.0/product/cluster_configuration/san_storage/lvm_drivers/) - [Virtual Machine Snapshot docs](https://docs.opennebula.io/7.0/management_and_operations/vm_management/snapshots/) Hope it helps. ---
**Author:** ![pnwjoe](https://avatars.discourse-cdn.com/v4/letter/p/2acd7d/32.png) [@pnwjoe](https://forum.opennebula.io/u/pnwjoe)\ **Post date:** [February 27, 2026, 8:01pm UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/3 "2026-02-27T20:01:43Z")
Thank you. So, in a nutshell, are you advocating creating new VG/lvols as thin from the start?? I created w/o any thin params and ex post facto ‘onedatastore update’ adding LVM\_THIN\_ENABLE=YES This POC is going REALLY well (want to move off vmware) but I need to get shapshots dialed in correctly Thank you Joe ---
**Author:** ![pnwjoe](https://avatars.discourse-cdn.com/v4/letter/p/2acd7d/32.png) [@pnwjoe](https://forum.opennebula.io/u/pnwjoe)\ **Post date:** [February 27, 2026, 8:01pm UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/4 "2026-02-27T20:01:55Z")
The “Virtual Machine Snaphots” link results in a 404. May I please have the correct link? ---
**Author:** ![FrancJP](https://yyz1.discourse-cdn.com/flex031/user_avatar/forum.opennebula.io/francjp/32/7690_2.png) [@FrancJP](https://forum.opennebula.io/u/FrancJP)\ **Post date:** [March 2, 2026, 9:47am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/5 "2026-03-02T09:47:17Z")
Sorry, the right url for the Snapshots is this one: [Snapshots](https://docs.opennebula.io/7.0/product/virtual_machines_operation/virtual_machines/vm_instances/#virtual-machine-system-snapshots) ---
**Author:** ![brunorro](https://yyz1.discourse-cdn.com/flex031/user_avatar/forum.opennebula.io/brunorro/32/7590_2.png) [@brunorro](https://forum.opennebula.io/u/brunorro)\ **Post date:** [March 2, 2026, 11:55am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/6 "2026-03-02T11:55:53Z")
Hello, Joe Unfortunately, `LVM_THIN_ENABLE` can only be modified at the moment of the datastore creation or when there are no images on the datastore. This is because in OpenNebula design, a LVM datastore cannot have both sort of thin and thick images. Thank you ---
**Author:** ![pnwjoe](https://avatars.discourse-cdn.com/v4/letter/p/2acd7d/32.png) [@pnwjoe](https://forum.opennebula.io/u/pnwjoe)\ **Post date:** [March 3, 2026, 8:23am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/7 "2026-03-03T08:23:20Z")
Thank you Bruno, I read that restriction after I created the VMs. However deleting the VMs (test VMs), updating the datastores with LVM\_THIN\_ENABLE didn’t modify the underlying lvols to thin. That seems not to work on my system (RHEL 9.7 + Pure array) as the fs\_lvm/clone script has no thin logic and snap\_create and just returns ‘Operation not supported’ ---
**Author:** ![brunorro](https://yyz1.discourse-cdn.com/flex031/user_avatar/forum.opennebula.io/brunorro/32/7590_2.png) [@brunorro](https://forum.opennebula.io/u/brunorro)\ **Post date:** [March 3, 2026, 9:20am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/8 "2026-03-03T09:20:03Z")
Mmmm… That is pretty strange. I understand that there are no LVs on that VG I cannot be totally sure but a quick test could be deleting and recreating the datastore, adding `LVM_THIN_ENABLE=yes` to the creation template. The datastore ID will be different but that can be the easiest way. Something like (being `${CURRENT_DATASTORE_ID}` the id of the current datastore) ```auto EDITOR=cat onedatastore update ${CURRENT_DATASTORE_ID} > ds_template echo "LVM_THIN_ENABLE=yes" >> ds_template echo "NAME=..." >> ds_template # choose the name to the new datastore onedatastore delete ${CURRENT_DATASTORE_ID} onedatastore create ds_template ID: ${NEW_DATASTORE_ID} # this will be the ID of the new datastore vgrename vg-one-${CURRENT_DATASTORE_ID} ${NEW_DATASTORE_ID} ``` If thin LVs are not enabled after I may ask you for some logs ---
**Author:** ![pnwjoe](https://avatars.discourse-cdn.com/v4/letter/p/2acd7d/32.png) [@pnwjoe](https://forum.opennebula.io/u/pnwjoe)\ **Post date:** [March 4, 2026, 6:57am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/9 "2026-03-04T06:57:23Z")
Tested with completely empty VG (no LVs, no thin pool). Created fresh datastore with LVM\_THIN\_ENABLE=yes from the start. ONE still creates standard LVs. Pool column empty, attr shows standard LV not thin. What logs would help debug this? `sudo lvs vg-one-104 -o lv_name,lv_size,pool_lv,lv_attr,data_percent` `LV LSize Pool Attr Data%` `lv-one-19-0 60.00m -wi-ao----` ---
**Author:** ![pnwjoe](https://avatars.discourse-cdn.com/v4/letter/p/2acd7d/32.png) [@pnwjoe](https://forum.opennebula.io/u/pnwjoe)\ **Post date:** [March 4, 2026, 6:57am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/10 "2026-03-04T06:57:50Z")
Hello OpenNebula, I really hate to do this but Claude is saying: ```auto cat /var/lib/one/remotes/tm/fs_lvm/clone | grep -i -A5 -B5 “lvcreate|thin” LV_NAME=“lv-one-$VM_ID-$DISK_ID” VG_NAME=“vg-one-$DS_SYS_ID” DEV=“/dev/${VG_NAME}/${LV_NAME}” Execute lvcreate with a lock in the frontend CREATE_CMD=$(cat < **Author:** ![pnwjoe](https://avatars.discourse-cdn.com/v4/letter/p/2acd7d/32.png) [@pnwjoe](https://forum.opennebula.io/u/pnwjoe)\ **Post date:** [March 12, 2026, 6:46am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/11 "2026-03-12T06:46:57Z") Any feedback please? We’ve invested a lot of time and effort into this and ON is our leading post-vmware hypervisor candidate, but if we cannot get thin volumes working we’ll have to consider other options. How can we engage ON on this? thank you. ---
**Author:** ![system](https://canada1.discourse-cdn.com/flex031/uploads/opennebula/original/2X/1/14d66f1130b9cd292905f575da9b68a9f574dd03.png) [@system](https://forum.opennebula.io/u/system)\ **Post date:** [April 11, 2026, 6:47am UTC](https://forum.opennebula.io/t/vm-snapshots-failing-on-on-7-0-1-on-san-lvols/14406/12 "2026-04-11T06:47:03Z")
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