Cause

Initially, when I started tinkering with PVE, I didn’t plan well and just attached a 128G SSD, meaning both the host and the VMs were on one disk.

As I tinkered more and more, the hard drive space was clearly insufficient, so I thought of replacing it with a larger SSD.

Problem

All data from the old disk was copied to the new disk. Then, during startup, it got stuck and displayed:

fsck exited with status code 4

I was puzzled. After some searching and tinkering, I recorded the solution process here.

It turned out to be caused by enabling hardware passthrough.

Solution

1. Enter Advanced Mode

   On boot, press the ↓ button and select “Advanced options for Proxmox Virtual Environment”.

   On the GRUB selection screen, press the e key to edit GRUB.

2. Edit GRUB

   Find the line with hardware passthrough, for example, mine was:

   linux /boot/vmlinuz-5.4.73-1-pve root=/dev/mapper/pve-root ro quiet intel_iommu=***********

   Change the `intel_iommu` value to `on`, or simply remove the assignment, like this:

   linux /boot/vmlinuz-5.4.73-1-pve root=/dev/mapper/pve-root ro quiet intel_iommu=on

   Note: My CPU is Intel; for AMD, this line should be `amd_iommu`.

   Then press Ctrl+O to save GRUB, Ctrl+X to exit, and boot from the new GRUB.

3. Update GRUB

   After entering the system, quickly modify the startup parameters in `/etc/default/grub`.

   Remove the item about passthrough under `GRUB_CMDLINE_LINUX_DEFAULT`, then update GRUB:

   update-grub

Problem 2

The issue caused by passthrough was resolved, but it got stuck again at boot, displaying:

a start job is running…

I suddenly remembered that I also mounted a mechanical hard drive via `fstab`. This was simple to fix.

After entering the system, edit `/etc/fstab` and comment out or delete that line.

With this, the process of replacing the main disk for PVE was completed.