# Resolving Inaccessible VM Due to Full Disk

By Abhishek, 2025-10-13. Canonical: https://www.va2pt.com/post/resolving-inaccessible-vm-due-to-full-disk

> This structured approach ensures minimal disruption while preserving data integrity and operational continuity.

## Introduction
A full disk on a virtual machine (VM) can render it inaccessible, disrupting normal operations. Recovering from such issues requires a methodical approach to restore VM functionality without data loss.

## Problem Statement
The VM is inaccessible due to a full disk, which prevents normal operations, including SSH access and system recovery.

### Proposed Solution
**Create a temporary VM to resolve disk issues by detaching, resizing, and reattaching the disk.**

#### Steps to Implement
1.  **Create a Temporary VM:**

    -   Deploy a new temporary VM in the same network and zone as the inaccessible VM.

2.  **Detach the Disk from the Inaccessible VM:**

    -   Use your cloud provider's console or CLI to detach the full disk.

3.  **Attach the Disk to the Temporary VM:**

    -   Mount the detached disk to the temporary VM for analysis and resizing.

4.  **Analyze and Free Space:**

    -   SSH into the temporary VM.

    -   Mount the disk and free up unnecessary files or resize the partition using tools like resize2fs or disk utilities.

```bash
sudo mount /dev/sdX1 /mnt/temp-disk sudo rm -rf /mnt/temp-disk/path-to-large-files
```

5.  **Detach and Reattach the Disk:**

    -   Unmount the disk from the temporary VM, detach it, and reattach it to the original VM.

2.  **Restart the Original VM:**

    -   Verify that the disk issue is resolved and the VM is accessible.

![Steps to Implement](/blog/resolving-inaccessible-vm-due-to-full-disk/img-1.webp)

## Why This Solution is Best
-   **Efficiency:** Directly addresses the issue by isolating the problematic disk.

-   **Data Integrity:** Preserves existing data during recovery.

-   **Minimized Downtime:** Allows for quick restoration without rebuilding the entire VM.

### Alternate Solutions
#### 1\. Create a New Machine from the VM Image
-   **Steps:**

    -   Use the cloud provider’s snapshot or image functionality to create a new VM from the existing image.

    -   Reconfigure services to use the new VM while retaining the same disk data.

-   **Pros:**

    -   Ensures continuity of operations without waiting for disk repairs.

-   **Cons:**

    -   Requires reconfigurations and may incur additional storage costs.

#### 2\. Use Serial Console to Free Up Space
-   **Steps:**

    -   Access the VM using the serial console.

    -   Free up space by removing unnecessary files or logs from /tmp, /var/log, or similar directories.

```
rm -rf /path-to-large-files
```

-   **Pros:**

    -   Quick fix without detaching the disk.

-   **Cons:**

    -   Requires familiarity with the serial console interface.

    -   Limited by the extent of disk usage.

## Summary
When a VM becomes inaccessible due to a full disk, isolating and repairing the disk via a temporary VM is the most effective solution. For less critical issues, creating a new VM from a snapshot or using the serial console can also provide viable alternatives.

This structured approach ensures minimal disruption while preserving data integrity and operational continuity.

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