Shared Disk between VMs

[tirili]

According http humblec com /how-to-share-a-disk-to-more-than-one-vm-using-libvirt-or-what-sharable-flag-do-in-libvirt/ there is the possibility to flag a disk image as shared between more than 1 VMs.

How is this achieveable using proxmox?

running

pvesh create /nodes/XXX/storage/pve/content -filename vm-1001-disk-sh-1 -format raw -size 5G --vmid 1001

creates a disk in PVE Storage.
How can I now flag it to use it as well in vmid 1002 and vmid 1003 respectively?

Any help is appreciated.
Best regards
Thomas

 

[tirili]

The solution is easy, but I am not quite sure if really correct:

* Stop VM
* Just add the disks in the Configuration File "/etc/pve/local/qemu-server/1001.conf" and "/etc/pve/local/qemu-server/1002.conf"

scsi1: pve:vm-1001-disk-sh-1
scsi2: pve:vm-1002-disk-sh-1
scsihw: virtio-scsi-pci

* Start the VMs
* Enjoy

But keep in mind, you need to use these only with a clustered Filesystem, e.g. GPFS etc. inside the VMs.

 

[LnxBil]

@tirili is right. Besides the clusteres filesystem remark, you also cannot create snaphots anymore or more precisely revert to them.

In situations where I need the snapshot capability, I install a third machine, configure iSCSI target. In my client nodes, I connect to the storage and are now able to snapshot all three machines to have a consistent state.

 

[tirili]

Is there any possibility to snapshot the "non shared" disks, and only keep the others out from the snapshot?

 

[Belokan]

I'm still waiting for the snapshot enable flag at vdisk level like existing "no backup" or "skip replication ones too:

https://forum.proxmox.com/threads/add-snapshot-0-option-to-hard-disk.43780/#post-209795

 

[LnxBil]

Is there any possibility to snapshot the "non shared" disks, and only keep the others out from the snapshot?

Only manually.