Proxmox VM - Windows 10 [One Disk Image, multiple VMs]

Apr 12, 2022
Hi People,

So what i wanted to achieve is i wanted one central Master VM disk and multiple VMS will be using the same as read only mode.

So my base vm let say vm 100 has windows 10 and lots of other softwares, and my other vms, vm101 to vm105 is using the same disk image of base windows vm with snapshot=1

For Ex:

VM 101:
sata0: zpool_data:vm-100-disk-0,size=60G,snapshot=1

VM 102:
sata0: zpool_data:vm-100-disk-0,size=60G,snapshot=1

The above configuration is done too maintain one source of disk image and install once and replicate every where, at the same time, if the system is rebooted it looses all changes which is crucial for us.

Also i have set the ips based on mac address using pfsense dhcp so static ips are assigned based on each vms network mac address.

The problem is, first 2 vms are running fine, but as soon as i start 3rd or 4th any one, i get this error.

TASK ERROR: start failed: command '/usr/bin/kvm -id 104 -name VM104 -no-shutdown -chardev 'socket,id=qmp,path=/var/run/qemu-server/104.qmp,server=on,wait=off' -mon 'chardev=qmp,mode=control' -chardev 'socket,id=qmp-event,path=/var/run/qmeventd.sock,reconnect=5' -mon 'chardev=qmp-event,mode=control' -pidfile /var/run/qemu-server/ -daemonize -smbios 'type=1,uuid=900c2c13-afe2-4c1e-983b-462c64fef32e' -smp '8,sockets=1,cores=8,maxcpus .... -rtc 'driftfix=slew,base=localtime' -machine 'smm=off,type=pc-q35-6.1+pve0' -global 'kvm-pit.lost_tick_policy=discard'' failed: got timeout

There is no order too it, if i start from the VM105, VM104, then VM103-2-1 fails.

Seems like only 2 vms are able to access the main disk image at any given point of time.

Any solution to this problem

** I have direct GPU passthrough enabled for each VM in the config.

Here is a sample config.

cores: 8
cpu: host
cpuunits: 10000
hostpci0: 0000:c3:00,pcie=1
machine: pc-q35-6.1
memory: 16096
meta: creation-qemu=6.1.0,ctime=1647679626
name: GVM3-115.54
net0: e1000=MAC_ADDRESS,bridge=vmbr1
numa: 0
ostype: win10
sata0: zpool_data:vm-100-disk-0,size=60G,snapshot=1
sata1: zpool_data:vm-100-disk-1,size=1500G,snapshot=1
scsihw: virtio-scsi-pci
smbios1: uuid=55.......
sockets: 1
vga: none
vmgenid: 19b4204d-7ee2-4189-91f6-a2dbc75126a5
Last edited:


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