---
title: Troubleshooting I/O errors and read-only file systems on Elastic Metal EM-A11XX-SSD servers
description: Learn about Linux kernel incompatibility issues affecting Elastic Metal EM-A11XX-SSD servers and how to resolve them.
tags: elastic-metal server linux kernel incompatibility
dates:
  validation: 2026-09-01
  posted: 2026-09-02
---

## Problem

On machines built on the Elastic Metal EM‑A11XX‑SSD line, you are encountering one or more of the following issues when running recent Linux kernels:

- Disks experience I/O packet loss
- The file system (e.g., EXT4) immediately switches to read‑only mode to protect the data
- System logs show DMA errors related to the IOMMU subsystem

This page explains the incompatibility causing the problem, lists the affected machines and operating systems, and provides a workaround.

## Affected machines and operating systems

The following **Elastic Metal servers** are affected by the incompatibility issue (specifically, only those built on the HP ProLiant DL320e Gen8 v2 chassis):

- EM‑A110X‑SSD
- EM‑A111X‑SSD
- EM‑A115X‑SSD
- EM‑A116X‑SSD

The following **operating systems and kernel versions** are affected:

- Ubuntu (kernels 7.x.x, e.g., Ubuntu 26.04)
- Debian / Proxmox VE (kernels ≥ 6.17.13, e.g., Debian Trixie)

## Cause

A default change in the handling of Intel IOMMU in recent Linux kernels (Debian/Ubuntu) degrades the SATA link (drops to 1.5 Gbps, AHCI link resets) and generates I/O errors on the disk controller via the IOMMU subsystem (`DMAR: ERROR: DMA PTE …`).

## Workaround

To resolve the issue without completely disabling IOMMU virtualization (VT‑d), configure the IOMMU in passthrough mode (`iommu=pt`).

1. Open a root terminal and create a dedicated GRUB configuration file:

   ```bash
   echo 'GRUB_CMDLINE_LINUX_DEFAULT="$GRUB_CMDLINE_LINUX_DEFAULT intel_iommu=on iommu=pt"' | sudo tee /etc/default/grub.d/iommu.cfg
   ```

2. Update the GRUB configuration:

   ```bash
   sudo update-grub
   ```

3. Reboot the server to apply the change:

   ```bash
   sudo reboot
   ```