Proxmox Installer Rebooting at “Waiting for /dev to Populate” on Dell PowerEdge T630

I recently hit a frustrating issue after biting the bullet, and moving away from ESXi 7.0 on my home lab, and installing Proxmox VE on a Dell PowerEdge T630 with fully updated firmware. The system would consistently reboot during boot of the installer, regardless of whether I used USB media, iDRAC virtual ISO, or other boot methods.

This post documents the exact symptom, the cause, and the fix.

The symptom

On booting the Proxmox installer, the system would reach the early kernel phase and then reboot hard with no visible kernel panic.

The last visible line before reboot was typically:

waiting for /dev to populate

This happened with:

• Physical USB installer created correctly

• iDRAC virtual ISO boot

• Multiple Proxmox ISO versions

• Freshly updated BIOS, iDRAC, Lifecycle Controller

It presented as unstable media at first glance, but the behaviour was consistent across methods.

Why this is confusing

“Waiting for /dev to populate” happens during early hardware enumeration. That is when the kernel initialises interrupt routing, DMA engines, and PCIe devices. A failure here often does not produce a clean kernel panic. Instead, the system watchdog triggers and the server simply reboots.

Because it happens before logging is properly established, it can easily be misdiagnosed as:

• Bad USB media

• Corrupt ISO

• Faulty RAM

• Storage controller issues

None of those were the root cause in this case.

The real cause

This turns out to be a known issue affecting some Dell PowerEdge platforms when booting newer Linux kernels, including Proxmox kernel 6.17.

Proxmox has documented this directly on their roadmap:

Potential issues booting into kernel 6.17 on some Dell PowerEdge servers
Some users have reported failure to boot into kernel 6.17 and machine check errors on certain Dell PowerEdge servers, while kernel 6.14 boots successfully. It is reported that enabling SR-IOV Global and I/OAT DMA in the firmware helps.

Source: Proxmox Roadmap 9.1 Known Issues

Reference:
https://pve.proxmox.com/wiki/Roadmap#9.1-known-issues

There is also a matching community thread describing identical reboot behaviour on Dell R630 systems:
https://forum.proxmox.com/threads/dell-poweredge-r630-reboots-immediately-on-kernel-6-17-2-2-pve-pwr2262-cpu0704-uefi0078.177201/

The fix

Enabling the following BIOS settings resolved the issue immediately:

• SR-IOV Global Enable

• I/OAT DMA Engine

• X2APIC Mode

After enabling these, the Proxmox installer booted cleanly and the system became fully stable.

This is not a Proxmox bug. It is a firmware interaction issue on older enterprise platforms where modern Linux kernels assume these features are available and correctly configured.

Where to find the settings on Dell PowerEdge T630

From boot:

F2 → System Setup
System BIOS → Processor Settings

• X2APIC Mode → Enabled

System BIOS → Integrated Devices

• SR-IOV Global Enable → Enabled

• I/OAT DMA Engine → Enabled

Save changes, reboot, then retry the installer.

If the system still fails to boot

Proxmox also recommends pinning the kernel to the older 6.14 series as a workaround:

proxmox-boot-tool kernel pin 6.14.11-4-pve

You can list available kernels with:

proxmox-boot-tool kernel list

This is useful if you inherit an already installed system that crashes after upgrades.

Why this matters

These servers are still extremely capable and widely used in homelabs and small production environments. The failure mode looks like bad media or hardware instability, which sends troubleshooting in the wrong direction.

The reality is simpler:

• Modern kernels expect certain firmware features to be enabled

• Some older Dell defaults leave them disabled

• The result is early boot instability with silent reboots

If you are seeing Proxmox reboot at “waiting for /dev to populate” on a PowerEdge T630, R630, or similar 13th gen platform, check the BIOS before replacing hardware.

Summary

Symptom: Proxmox installer reboots during early boot at “waiting for /dev to populate”
Cause: Firmware features disabled on older PowerEdge platforms
Fix: Enable SR-IOV Global, I/OAT DMA, and X2APIC in BIOS
Alternative workaround: Pin Proxmox kernel to 6.14

This small changes turned an unusable system into a stable platform.