Hibernation Support for Linux Azure virtual machines
By: Date: 16/10/2025 Categories: azure Tags:

Linux VM hibernation in Microsoft Azure enables virtual machines to pause execution while preserving the full in-memory state to disk. When the VM is started again, the Linux OS resumes exactly from where it left off—processes, applications, and sessions intact.

This feature is designed for cost optimization and fast resume for stateful Linux workloads.

Supported Scenarios

✔ Select Gen2 VM sizes
✔ Managed OS disks (Premium SSD / Standard SSD)
✔ Supported Linux distributions (newer kernels required)
✔ Azure portal, CLI, or ARM-based hibernate actions

Key Benefits

  • No compute charges while hibernated.
  • Storage charges still apply (OS and data disks).
  • Much quicker than a full boot for memory-intensive workloads.

Supported VM sizes

VM sizes with up to 64-GB RAM from the following General Purpose VM series support hibernation.

VM sizes with up to 112-GB RAM from the following GPU VM series support hibernation.

If you are using any UVM-enabled compute applications, we recommend idling the application before initiating hibernation.

Supported Linux distros

The following Linux operating systems support hibernation:

  • Ubuntu 22.04 LTS (Long-Term Support)
  • Ubuntu 20.04 LTS (Long-Term Support)
  • Ubuntu 18.04 LTS (Long-Term Support)
  • Debian 11
  • Debian 10 (with backports kernel)
  • Red Hat Enterprise Linux 9.0 and higher (with minimum kernel version 5.14.0-70)
  • Red Hat Enterprise Linux 8.5 and higher (with minimum kernel version 4.18.0-348)

Prerequisites for Using Hibernation

Before enabling hibernation on an Azure VM, ensure the following:

  • Hibernation is enabled on the VM.
  • Persistent OS disk is attached with enough space to store:
    • RAM contents
    • Operating system
    • Applications running on the VM
  • VM size supports hibernation.
  • Operating system supports hibernation.
  • Azure VM Agent is installed, if using Windows or Linux Hibernate Extensions.
  • If creating a VM from an OS disk or Compute Gallery image, ensure the disk or image definition supports hibernation.

How to Enable Hibernation When Creating a Linux VM in Azure

To enable hibernation in the Azure portal, check the ‘Enable hibernation’ box during VM creation.

Enabling hibernation on an existing Linux VM

To enable hibernation on an existing VM, you can use Azure CLI, PowerShell, or REST API. Before proceeding, ensure that the guest OS version supports hibernation on Azure.

To enable hibernation on an existing VM using Azure CLI, first deallocate your VM with az vm deallocate. Once the VM is deallocated, update the OS disk and VM.

Azure CLI

  1. Update the OS disk to set supportsHibernation to true. If supportsHibernation is already set to true, you can skip this step and proceed to the next step.

az disk update –resource-group myResourceGroup –name MyOSDisk –set supportsHibernation=true

2. Update the VM to enable hibernation.

az vm update –resource-group myResourceGroup –name myVM –enable-hibernation true

3. Start the VM and then proceed to configuring hibernation in the guest OS.

az vm start –resource-group myResourceGroup –name myVM

Reference: Hibernating Linux virtual machines

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