The qemu-guest-agent is a common helper daemon, which is installed in a guest OS on a hypervisor. It is used to exchange information between the host and guest, and to execute command in the guest. In Proxmox VE, the qemu-guest-agent is used for mainly three things: To properly shutdown the guest, instead of relying on ACPI commands or windows policies To freeze the guest file system when making a backup/snapshot (on windows, use the volume shadow copy service VSS). If the guest agent is enabled and running, it calls guest-fsfreeze-freeze and guest-fsfreeze-thaw to improve consistency. In the phase when the guest (VM) is resumed after pause (for example after shapshot) it immediately synchronizes its time with the hypervisor using qemu-guest-agent (as first step). As LiquidFiles does not appear to support qemu-guest-agent, host shutdowns usually result in timeouts and/or forced shutdown.
Natively this agent is not installed because majority of LF appliances are not deployed on Proxmox hosts. Although in the stock Ubuntu 22.04 kernels, which LF is using, include the core kernel features Proxmox needs (KVM, networking, block devices etc. so you get basic virtualization support out of the box. The quemu-guest-agent can be optionally installed in the root shell from the system repos when needed: apt update apt install qemu-guest-agent systemctl enable qemu-guest-agent systemctl start qemu-guest-agent
