Hello,
I faced a strange problem with one of my VMs on Proxmox VE.
This is an Ubuntu VM which resides on a ZFS thick storage.
On 31 October 2026 I reconfigured the VM, added CPUs and RAM but did not reboot the VM to apply changes because the VM was in use and these additional resources were not very critical.
On 6 November 2026 I added a disk space to the partition which is mounted as a large ext4 LVM volume on /var/www. Then I did standard live resize procedure (pvresize, lvextend -r -l +100%FREE ...), all completed successfully.
On 7 November 2026 I finally rebooted the VM and new resources in CPU adn RAM were applied.
On 9 November I got messages from the VM users that they do not see the files and Mysql DB changes which were done from approximately from 31 October and till 6-7 November.
I have a VM backup for 7 November which was finished before I rebooted it. After restoring it to another VM instance I saw that all the lost changes in files and DB were there, so the problem was partially solved.
But I still do not understand the source of the problem.
Here is what I found:
1) The VM had no snapshots. The last VM snapshot was done about half a year ago and deleted as unnecessary anymore.
2) The VM had cloud-init options applied, all of them very basic and done with Proxmox GUI. After reboot the cloud-init service was applied again because I did not disabled cloud init and previously unchecked the box "update packages".
So ssh host keys were changed after reboot but this was the only problem I noticed by myself.
For me it looks like rebooting restored the VM state to the date I changed the CPU and RAM settings and left them not applied but I do not see any " old state source" for this VM.
Now I am not sure if it is safe to reboot the VM once again. I know, I do have recent backups every day, I can do snapshots before reboot, that is ok. But the changes our users do to the VM and Mysql DB (this is a web portal) are not very easy to track and can be noticed long after reboot which makes snapshots not very useful.
Any help in understanding the cause of the problem would be very appreciated.
I faced a strange problem with one of my VMs on Proxmox VE.
This is an Ubuntu VM which resides on a ZFS thick storage.
On 31 October 2026 I reconfigured the VM, added CPUs and RAM but did not reboot the VM to apply changes because the VM was in use and these additional resources were not very critical.
On 6 November 2026 I added a disk space to the partition which is mounted as a large ext4 LVM volume on /var/www. Then I did standard live resize procedure (pvresize, lvextend -r -l +100%FREE ...), all completed successfully.
On 7 November 2026 I finally rebooted the VM and new resources in CPU adn RAM were applied.
On 9 November I got messages from the VM users that they do not see the files and Mysql DB changes which were done from approximately from 31 October and till 6-7 November.
I have a VM backup for 7 November which was finished before I rebooted it. After restoring it to another VM instance I saw that all the lost changes in files and DB were there, so the problem was partially solved.
But I still do not understand the source of the problem.
Here is what I found:
1) The VM had no snapshots. The last VM snapshot was done about half a year ago and deleted as unnecessary anymore.
2) The VM had cloud-init options applied, all of them very basic and done with Proxmox GUI. After reboot the cloud-init service was applied again because I did not disabled cloud init and previously unchecked the box "update packages".
So ssh host keys were changed after reboot but this was the only problem I noticed by myself.
For me it looks like rebooting restored the VM state to the date I changed the CPU and RAM settings and left them not applied but I do not see any " old state source" for this VM.
Now I am not sure if it is safe to reboot the VM once again. I know, I do have recent backups every day, I can do snapshots before reboot, that is ok. But the changes our users do to the VM and Mysql DB (this is a web portal) are not very easy to track and can be noticed long after reboot which makes snapshots not very useful.
Any help in understanding the cause of the problem would be very appreciated.
Code:
proxmox-ve: 8.4.0 (running kernel: 6.8.12-15-pve)
pve-manager: 8.4.14 (running version: 8.4.14/b502d23c55afcba1)
proxmox-kernel-helper: 8.1.4
proxmox-kernel-6.8: 6.8.12-15
proxmox-kernel-6.8.12-15-pve-signed: 6.8.12-15
proxmox-kernel-6.8.12-9-pve-signed: 6.8.12-9
ceph-fuse: 17.2.8-pve2
corosync: 3.1.9-pve1
criu: 3.17.1-2+deb12u2
frr-pythontools: 10.2.3-1+pve1
glusterfs-client: 10.3-5
ifupdown2: 3.2.0-1+pmx11
ksm-control-daemon: 1.5-1
libjs-extjs: 7.0.0-5
libknet1: 1.30-pve2
libproxmox-acme-perl: 1.6.0
libproxmox-backup-qemu0: 1.5.2
libproxmox-rs-perl: 0.3.5
libpve-access-control: 8.2.2
libpve-apiclient-perl: 3.3.2
libpve-cluster-api-perl: 8.1.2
libpve-cluster-perl: 8.1.2
libpve-common-perl: 8.3.4
libpve-guest-common-perl: 5.2.2
libpve-http-server-perl: 5.2.2
libpve-network-perl: 0.11.2
libpve-rs-perl: 0.9.4
libpve-storage-perl: 8.3.7
libspice-server1: 0.15.1-1
lvm2: 2.03.16-2
lxc-pve: 6.0.0-1
lxcfs: 6.0.0-pve2
novnc-pve: 1.6.0-2
proxmox-backup-client: 3.4.6-1
proxmox-backup-file-restore: 3.4.6-1
proxmox-backup-restore-image: 0.7.0
proxmox-firewall: 0.7.1
proxmox-kernel-helper: 8.1.4
proxmox-mail-forward: 0.3.3
proxmox-mini-journalreader: 1.5
proxmox-offline-mirror-helper: 0.6.8
proxmox-widget-toolkit: 4.3.13
pve-cluster: 8.1.2
pve-container: 5.3.3
pve-docs: 8.4.1
pve-edk2-firmware: 4.2025.02-4~bpo12+1
pve-esxi-import-tools: 0.7.4
pve-firewall: 5.1.2
pve-firmware: 3.16-3
pve-ha-manager: 4.0.7
pve-i18n: 3.4.5
pve-qemu-kvm: 9.2.0-7
pve-xtermjs: 5.5.0-2
qemu-server: 8.4.3
smartmontools: 7.3-pve1
spiceterm: 3.3.1
swtpm: 0.8.0+pve1
vncterm: 1.8.1
zfsutils-linux: 2.2.8-pve1