Proxmox SPICE mouse not aligned? The pointer is offset because SPICE uses absolute positioning while the guest still thinks it’s relative. Enable tablet mode and install the guest agent, and the offset goes away.
Why the mouse is off
SPICE works best with an absolute pointing device. When the VM doesn’t expose one, the client falls back to relative mode and the cursor drifts. The fix is to make the guest see a tablet, not a plain mouse.
Enable tablet mode
In the VM’s hardware settings, set Use tablet for pointer to Yes. This is the single most important setting. Without it, SPICE will always be out of sync.
qm set <vmid> --tablet 1If the checkbox is already on and the offset persists, the guest is missing the agent.
Install the guest agent
Windows needs spice-vdagent from the SPICE guest tools. Linux guests need spice-vdagent installed and running. The agent tells the guest to switch to absolute mode when SPICE connects.
# Debian/Ubuntu
apt install spice-vdagent
systemctl enable --now spice-vdagent
# RHEL/Fedora
dnf install spice-vdagent
systemctl enable --now spice-vdagentCheck that the service is active. A common failure is installing the agent but not enabling it, so the guest stays in relative mode.
Scaling and resolution
If the offset only appears when the window is scaled, the client and guest disagree on the display size. Set the SPICE client to Auto-resize VM with window and make sure the guest resolution matches. Mismatched scaling keeps the cursor off even with tablet mode enabled.
What I’d do
Check tablet mode first, then the agent. That order fixes most cases. If it’s still off, look at scaling. The offset is never random—it’s always one of those three.
For more on Proxmox quirks, see Cloud-Init drive shows as CD-ROM.
