# Hibernate your Amazon EC2 instance When you hibernate an instance, Amazon EC2 signals the operating system to perform hibernation (suspend-to-disk). Hibernation saves the contents from the instance memory (RAM) to your Amazon Elastic Block Store (Amazon EBS) root volume. Amazon EC2 persists the instance's EBS root volume and any attached EBS data volumes. When your instance is started: + The EBS root volume is restored to its previous state + The RAM contents are reloaded + The processes that were previously running on the instance are resumed + Previously attached data volumes are reattached and the instance retains its instance ID You can hibernate an instance only if it's [enabled for hibernation](enabling-hibernation.md) and it meets the [hibernation prerequisites](hibernating-prerequisites.md). If an instance or application takes a long time to bootstrap and build a memory footprint in order to become fully productive, you can use hibernation to pre-warm the instance. To pre-warm the instance, you: 1. Launch it with hibernation enabled. 1. Bring it to a desired state. 1. Hibernate it so that it's ready to be resumed to the desired state whenever needed. You're not charged for instance usage for a hibernated instance when it is in the `stopped` state or for data transfer when the contents of the RAM are transferred to the EBS root volume. You are charged for storage of any EBS volumes, including storage for the RAM contents. If you no longer need an instance, you can terminate it at any time, including when it is in a `stopped` (hibernated) state. For more information, see [Terminate Amazon EC2 instances](terminating-instances.md). **Topics** + [How it works](instance-hibernate-overview.md) + [Prerequisites](hibernating-prerequisites.md) + [Configure a Linux AMI to support hibernation](hibernation-enabled-AMI.md) + [Enable instance hibernation](enabling-hibernation.md) + [Disable KASLR on an instance (Ubuntu only)](hibernation-disable-kaslr.md) + [Hibernate an instance](hibernating-instances.md) + [Start a hibernated instance](hibernating-resuming.md) + [Troubleshoot](troubleshoot-instance-hibernate.md) # How Amazon EC2 instance hibernation works The following diagram shows a basic overview of the hibernation process for EC2 instances. ![\[Overview of the hibernation flow.\]](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/images/hibernation-flow.png) ## What happens when you hibernate an instance When you hibernate an instance, the following happens: + The instance moves to the `stopping` state. Amazon EC2 signals the operating system to perform hibernation (suspend-to-disk). The hibernation freezes all of the processes, saves the contents of the RAM to the EBS root volume, and then performs a regular shutdown. + After the shutdown is complete, the instance moves to the `stopped` state. + Any EBS volumes remain attached to the instance, and their data persists, including the saved contents of the RAM. + Any Amazon EC2 instance store volumes remain attached to the instance, but the data on the instance store volumes is lost. + In most cases, the instance is migrated to a new underlying host computer when it's started. This is also what happens when you stop and start an instance. + When the instance is started, the instance boots up and the operating system reads in the contents of the RAM from the EBS root volume, before unfreezing processes to resume its state. + The instance retains its private IPv4 addresses and any IPv6 addresses. When the instance is started, the instance continues to retain its private IPv4 addresses and any IPv6 addresses. + Amazon EC2 releases the public IPv4 address. When the instance is started, Amazon EC2 assigns a new public IPv4 address to the instance. + The instance retains its associated Elastic IP addresses. You're charged for any Elastic IP addresses that are associated with a hibernated instance. For information about how hibernation differs from reboot, stop, and terminate, see [Differences between instance states](ec2-instance-lifecycle.md#lifecycle-differences). ## Limitations + When you hibernate an instance, the data on any instance store volumes is lost. + (Linux instances) You can't hibernate a Linux instance that has more than 150 GiB of RAM. + (Windows instances) You can't hibernate a Windows instance that has more than 16 GiB of RAM. + While your instance is hibernated, you can't modify it. This is different to a stopped instance that isn't hibernated, where you can modify certain attributes, such as the instance type or size. + If you create a snapshot or AMI from an instance that is hibernated or has hibernation enabled, you might not be able to connect to a new instance that is launched from the AMI or from an AMI that was created from the snapshot. + (Spot Instances only) If Amazon EC2 hibernates your Spot Instance, only Amazon EC2 can resume your instance. If you hibernate your Spot Instance ([user-initiated hibernation](hibernating-instances.md)), you can resume your instance. A hibernated Spot Instance can only be resumed if capacity is available and the Spot price is less than or equal to your specified maximum price. + You can't hibernate an instance that is in an Auto Scaling group or used by Amazon ECS. If your instance is in an Auto Scaling group and you try to hibernate it, the Amazon EC2 Auto Scaling service marks the stopped instance as unhealthy, and might terminate it and launch a replacement instance. For more information, see [Health checks for instances in an Auto Scaling group](https://docs.aws.amazon.com/autoscaling/ec2/userguide/ec2-auto-scaling-health-checks.html) in the *Amazon EC2 Auto Scaling User Guide*. + You can't hibernate an instance that is configured to boot in UEFI mode with [UEFI Secure Boot](uefi-secure-boot.md) enabled. + If you hibernate an instance that was launched into a Capacity Reservation, the Capacity Reservation does not ensure that the hibernated instance can resume after you try to start it. + You can’t hibernate an instance that uses a kernel below 5.10 if Federal Information Processing Standard (FIPS) mode is enabled. + We do not support keeping an instance hibernated for more than 60 days. To keep the instance for longer than 60 days, you must start the hibernated instance, stop the instance, and start it. + We constantly update our platform with upgrades and security patches, which can conflict with existing hibernated instances. We notify you about critical updates that require a start for hibernated instances so that we can perform a shutdown or a reboot to apply the necessary upgrades and security patches. ## Considerations for hibernating a Spot Instance + If *you* hibernate your Spot Instance, you can restart it provided capacity is available and the Spot price is less than or equal to your specified maximum price. + If *Amazon EC2* hibernates your Spot Instance: + Only Amazon EC2 can resume your instance. + Amazon EC2 resumes the hibernated Spot Instance when capacity becomes available with a Spot price that is less than or equal to your specified maximum price. + Before Amazon EC2 hibernates your Spot Instance, you'll receive an interruption notice two minutes before hibernation starts. For more information, see [Spot Instance interruptions](spot-interruptions.md). # Prerequisites for EC2 instance hibernation You can enable hibernation support for an On-Demand Instance or a Spot Instance when you launch it. You can't enable hibernation on an existing instance, whether it is running or stopped. For more information, see [Enable instance hibernation](enabling-hibernation.md). **Topics** + [AWS Regions](#hibernation-prereqs-regions) + [AMIs](#hibernation-prereqs-supported-amis) + [Instance families](#hibernation-prereqs-supported-instance-families) + [Instance RAM size](#instance-ram-size) + [Root volume type](#hibernation-prereqs-root-volume-type) + [Root volume size](#hibernation-prereqs-ebs-root-volume-size) + [Root volume encryption](#hibernation-prereqs-ebs-root-volume-encryption) + [EBS volume type](#hibernation-prereqs-ebs-volume-types) + [Spot Instance requests](#hibernation-prereqs-spot-request) ## AWS Regions You can use hibernation with instances in all AWS Regions. ## AMIs You must use an HVM AMI that supports hibernation. The following AMIs support hibernation: ### Linux AMIs **AMIs for Intel and AMD instance types** + AL2023 AMI released 2023.09.20 or later ¹ + Amazon Linux 2 AMI released 2019.08.29 or later + Amazon Linux AMI 2018.03 released 2018.11.16 or later + CentOS version 8 AMI ² ([Additional configuration](hibernation-enabled-AMI.md#configure-centos-for-hibernation) is required) + Fedora version 34 or later AMI ² ([Additional configuration](hibernation-enabled-AMI.md#configure-fedora-for-hibernation) is required) + Red Hat Enterprise Linux (RHEL) 9 AMI ² ([Additional configuration](hibernation-enabled-AMI.md#configure-RHEL-for-hibernation) is required) + Red Hat Enterprise Linux (RHEL) 8 AMI ² ([Additional configuration](hibernation-enabled-AMI.md#configure-RHEL-for-hibernation) is required) + Ubuntu 22.04.2 LTS (Jammy Jellyfish) AMI released with serial number 20230303 or later ³ + Ubuntu 20.04 LTS (Focal Fossa) AMI released with serial number 20210820 or later ³ + Ubuntu 18.04 LTS (Bionic Beaver) AMI released with serial number 20190722.1 or later ³ ⁵ + Ubuntu 16.04 LTS (Xenial Xerus) AMI ³ ⁴ ⁵ ([Additional configuration](hibernation-enabled-AMI.md#configure-ubuntu1604-for-hibernation) is required) **AMIs for Graviton instance types** + AL2023 AMI (64-bit Arm) released 2024.07.01 or later ¹ + Amazon Linux 2 AMI (64-bit Arm) released 2024.06.20 or later + Ubuntu 22.04.2 LTS (64-bit Arm) (Jammy Jellyfish) AMI released with serial number 20240701 or later ³ + Ubuntu 20.04 LTS (64-bit Arm) (Focal Fossa) AMI released with serial number 20240701 or later ³   ¹ For AL2023 minimal AMI, [additional configuration is required](hibernation-enabled-AMI.md#configure-AL2023-minimal-for-hibernation). ² For CentOS, Fedora, and Red Hat Enterprise Linux, hibernation is supported on Nitro-based instances only. ³ We recommend disabling KASLR on instances with Ubuntu 22.04.2 LTS (Jammy Jellyfish), Ubuntu 20.04 LTS (Focal Fossa), Ubuntu 18.04 LTS (Bionic Beaver), and Ubuntu 16.04 LTS (Xenial Xerus). For more information, see [Disable KASLR on an instance (Ubuntu only)](hibernation-disable-kaslr.md). ⁴ For the Ubuntu 16.04 LTS (Xenial Xerus) AMI, hibernation is not supported on `t3.nano` instance types. No patch will be made available because Ubuntu (Xenial Xerus) ended support in April 2021. If you want to use `t3.nano` instance types, we recommend that you upgrade to the Ubuntu 22.04.2 LTS (Jammy Jellyfish), Ubuntu 20.04 LTS (Focal Fossa) AMI, or the Ubuntu 18.04 LTS (Bionic Beaver) AMI. ⁵ Support for Ubuntu 18.04 LTS (Bionic Beaver) and Ubuntu 16.04 LTS (Xenial Xerus) has reached end of life. To configure your own AMI to support hibernation, see [Configure a Linux AMI to support hibernation](hibernation-enabled-AMI.md). Support for other versions of Ubuntu and other operating systems is coming soon. ### Windows AMIs + Windows Server 2022 AMI released 2023.09.13 or later + Windows Server 2019 AMI released 2019.09.11 or later + Windows Server 2016 AMI released 2019.09.11 or later + Windows Server 2012 R2 AMI released 2019.09.11 or later + Windows Server 2012 AMI released 2019.09.11 or later ## Instance families You must use an instance family that supports hibernation. However, bare metal instances are not supported. + General purpose: M3, M4, M5, M5a, M5ad, M5d, M6a, M6g, M6gd, M6i, M6id, M6idn, M6in, M7a, M7g, M7gd, M7i, M7i-flex, M8a, M8azn, M8g, M8gb, M8gd, M8gn, M8i, M8i-flex, T2, T3, T3a, T4g + Compute optimized: C3, C4, C5, C5d, C6a, C6g, C6gd, C6gn, C6i, C6id, C6in, C7a, C7g, C7gd, C7gn, C7i, C7i-flex, C8a, C8g, C8gb, C8gd, C8gn, C8i, C8i-flex + Memory optimized: R3, R4, R5, R5a, R5ad, R5d, R6a, R6g, R6gd, R6idn, R6in, R7a, R7g, R7gd, R7i, R7iz, R8a, R8g, R8gb, R8gd, R8gn, R8i, R8i-flex, X2gd, X8aedz, X8i + Storage optimized: I3, I3en, I4g, I7i, I7ie, I8g, I8ge, Im4gn, Is4gen ------ #### [ Console ] **To get the instance types that support hibernation** 1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/). 1. In the navigation pane, choose **Instance Types**. 1. Add the filter **On-Demand Hibernation support = true**. 1. (Optional) Add filters to further scope to specific instance types of interest. ------ #### [ AWS CLI ] **To get the instance types that support hibernation** Use the [describe-instance-types](https://docs.aws.amazon.com/cli/latest/reference/describe-instance-types/.html) command. Note that the available instance types vary by Region. ``` aws ec2 describe-instance-types \ --filters Name=hibernation-supported,Values=true \ --query "InstanceTypes[*].[InstanceType]" \ --output text | sort ``` ------ #### [ PowerShell ] **To get the instance types that support hibernation** Use the [Get-EC2InstanceType](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-EC2InstanceType.html) cmdlet. Note that the available instance types vary by Region. ``` (Get-EC2InstanceType ` -Filter @{Name="hibernation-supported"; Values="true"}).InstanceType | Sort-Object ``` ------ ## Instance RAM size **Linux instances** – Must be less than 150 GiB. **Windows instances** – Must be less than or equal to 16 GiB. For hibernating a T3 or T3a Windows instance, we recommend at least 1 GiB of RAM. ## Root volume type The root volume must be an EBS volume, not an instance store volume. ## Root volume size The root volume must be large enough to store the RAM contents and accommodate your expected usage, for example, OS or applications. If you enable hibernation, space is allocated on the root volume at launch to store the RAM. ## Root volume encryption The root volume must be encrypted to ensure the protection of sensitive content that is in memory at the time of hibernation. When RAM data is moved to the EBS root volume, it is always encrypted. Encryption of the root volume is enforced at instance launch. Use one of the following three options to ensure that the root volume is an encrypted EBS volume: + **EBS encryption by default** – You can enable EBS encryption by default to ensure that all new EBS volumes created in your AWS account are encrypted. This way, you can enable hibernation for your instances without specifying encryption intent at instance launch. For more information, see [Enable encryption by default](https://docs.aws.amazon.com/ebs/latest/userguide/encryption-by-default.html). + **EBS "single-step" encryption** – You can launch encrypted EBS-backed EC2 instances from an unencrypted AMI and also enable hibernation at the same time. For more information, see [Use encryption with EBS-backed AMIs](AMIEncryption.md). + **Encrypted AMI** – You can enable EBS encryption by using an encrypted AMI to launch your instance. If your AMI does not have an encrypted root snapshot, you can copy it to a new AMI and request encryption. For more information, see [Encrypt an unencrypted image during copy](AMIEncryption.md#copy-unencrypted-to-encrypted) and [Copy an AMI](CopyingAMIs.md#ami-copy-steps). ## EBS volume type The EBS volumes must use one of the following EBS volume types: + General Purpose SSD (`gp2` and `gp3`) + Provisioned IOPS SSD (`io1` and `io2`) If you choose a Provisioned IOPS SSD volume type, you must provision the EBS volume with the appropriate IOPS to achieve optimum performance for hibernation. For more information, see [Amazon EBS volume types](https://docs.aws.amazon.com/ebs/latest/userguide/ebs-volume-types.html) in the *Amazon EBS User Guide*. ## Spot Instance requests For Spot Instances, the following requirements apply: + The Spot Instance request type must be `persistent`. + You can't specify a launch group in the Spot Instance request. # Configure a Linux AMI to support hibernation The following Linux AMIs can support hibernating an Amazon EC2 instance, provided you complete the additional configuration steps described in this section. **Topics** + [AL2023 minimal AMI released 2023.09.20 or later](#configure-AL2023-minimal-for-hibernation) + [Amazon Linux 2 minimal AMI released 2019.08.29 or later](#configure-AL2-minimal-for-hibernation) + [Amazon Linux 2 released before 2019.08.29](#configure-AL2-for-hibernation) + [Amazon Linux released before 2018.11.16](#configure-AL-for-hibernation) + [CentOS version 8 or later](#configure-centos-for-hibernation) + [Fedora version 34 or later](#configure-fedora-for-hibernation) + [Red Hat Enterprise Linux version 8 or 9](#configure-RHEL-for-hibernation) + [Ubuntu 20.04 LTS (Focal Fossa) released before serial number 20210820](#configure-ubuntu2004-for-hibernation) + [Ubuntu 18.04 (Bionic Beaver) released before serial number 20190722.1](#configure-ubuntu1804-for-hibernation) + [Ubuntu 16.04 (Xenial Xerus)](#configure-ubuntu1604-for-hibernation) For the Linux and Windows AMIs that support hibernation and for which *no additional* configuration is required, see [AMIs](hibernating-prerequisites.md#hibernation-prereqs-supported-amis). For more information, see [Update instance software on your Amazon Linux 2 instance](https://docs.aws.amazon.com/linux/al2/ug/install-updates.html). ## AL2023 minimal AMI released 2023.09.20 or later **To configure an AL2023 minimal AMI released 2023.09.20 or later to support hibernation** 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo dnf install ec2-hibinit-agent ``` 1. Restart the service. ``` [ec2-user ~]$ sudo systemctl start hibinit-agent ``` ## Amazon Linux 2 minimal AMI released 2019.08.29 or later **To configure an Amazon Linux 2 minimal AMI released 2019.08.29 or later to support hibernation** 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo yum install ec2-hibinit-agent ``` 1. Restart the service. ``` [ec2-user ~]$ sudo systemctl start hibinit-agent ``` ## Amazon Linux 2 released before 2019.08.29 **To configure an Amazon Linux 2 AMI released before 2019.08.29 to support hibernation** 1. Update the kernel to `4.14.138-114.102` or later. ``` [ec2-user ~]$ sudo yum update kernel ``` 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo yum install ec2-hibinit-agent ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `4.14.138-114.102` or later. ``` [ec2-user ~]$ uname -a ``` 1. Stop the instance and create an AMI. For more information, see [Create an Amazon EBS-backed AMI](creating-an-ami-ebs.md). ## Amazon Linux released before 2018.11.16 **To configure an Amazon Linux AMI released before 2018.11.16 to support hibernation** 1. Update the kernel to `4.14.77-70.59` or later. ``` [ec2-user ~]$ sudo yum update kernel ``` 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo yum install ec2-hibinit-agent ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `4.14.77-70.59` or greater. ``` [ec2-user ~]$ uname -a ``` 1. Stop the instance and create an AMI. For more information, see [Create an Amazon EBS-backed AMI](creating-an-ami-ebs.md). ## CentOS version 8 or later **To configure a CentOS version 8 or later AMI to support hibernation** 1. Update the kernel to `4.18.0-305.7.1.el8_4.x86_64` or later. ``` [ec2-user ~]$ sudo yum update kernel ``` 1. Install the Fedora Extra Packages for Enterprise Linux (EPEL) repository. ``` [ec2-user ~]$ sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm ``` 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo yum install ec2-hibinit-agent ``` 1. Enable the hibernate agent to start on boot. ``` [ec2-user ~]$ sudo systemctl enable hibinit-agent.service ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `4.18.0-305.7.1.el8_4.x86_64` or later. ``` [ec2-user ~]$ uname -a ``` ## Fedora version 34 or later **To configure a Fedora version 34 or later AMI to support hibernation** 1. Update the kernel to `5.12.10-300.fc34.x86_64` or later. ``` [ec2-user ~]$ sudo yum update kernel ``` 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo dnf install ec2-hibinit-agent ``` 1. Enable the hibernate agent to start on boot. ``` [ec2-user ~]$ sudo systemctl enable hibinit-agent.service ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `5.12.10-300.fc34.x86_64` or later. ``` [ec2-user ~]$ uname -a ``` ## Red Hat Enterprise Linux version 8 or 9 **To configure a Red Hat Enterprise Linux 8 or 9 AMI to support hibernation** 1. Update the kernel to `4.18.0-305.7.1.el8_4.x86_64` or later. ``` [ec2-user ~]$ sudo yum update kernel ``` 1. Install the Fedora Extra Packages for Enterprise Linux (EPEL) repository. RHEL version 8: ``` [ec2-user ~]$ sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm ``` RHEL version 9: ``` [ec2-user ~]$ sudo yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-9.noarch.rpm ``` 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo yum install ec2-hibinit-agent ``` 1. Enable the hibernate agent to start on boot. ``` [ec2-user ~]$ sudo systemctl enable hibinit-agent.service ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `4.18.0-305.7.1.el8_4.x86_64` or later. ``` [ec2-user ~]$ uname -a ``` ## Ubuntu 20.04 LTS (Focal Fossa) released before serial number 20210820 **To configure an Ubuntu 20.04 LTS (Focal Fossa) AMI released before serial number 20210820 to support hibernation** 1. Update the linux-aws-kernel to `5.8.0-1038.40` or later, and grub2 to `2.04-1ubuntu26.13` or later. ``` [ec2-user ~]$ sudo apt update [ec2-user ~]$ sudo apt dist-upgrade ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `5.8.0-1038.40` or later. ``` [ec2-user ~]$ uname -a ``` 1. Confirm that the grub2 version is updated to `2.04-1ubuntu26.13` or later. ``` [ec2-user ~]$ dpkg --list | grep grub2-common ``` ## Ubuntu 18.04 (Bionic Beaver) released before serial number 20190722.1 **To configure an Ubuntu 18.04 LTS AMI released before serial number 20190722.1 to support hibernation** 1. Update the kernel to `4.15.0-1044` or later. ``` [ec2-user ~]$ sudo apt update [ec2-user ~]$ sudo apt dist-upgrade ``` 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo apt install ec2-hibinit-agent ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `4.15.0-1044` or later. ``` [ec2-user ~]$ uname -a ``` ## Ubuntu 16.04 (Xenial Xerus) To configure Ubuntu 16.04 LTS to support hibernation, you need to install the linux-aws-hwe kernel package version 4.15.0-1058-aws or later and the ec2-hibinit-agent. **Important** The `linux-aws-hwe` kernel package is supported by Canonical. The standard support for Ubuntu 16.04 LTS ended in April 2021, and the package no longer receives regular updates. However, it will receive additional security updates until the Extended Security Maintenance support ends in 2024. For more information, see [Amazon EC2 Hibernation for Ubuntu 16.04 LTS now available](https://ubuntu.com/blog/amazon-ec2-hibernation-for-ubuntu-16-04-lts-now-available) on the Canonical Ubuntu Blog. We recommend that you upgrade to the Ubuntu 20.04 LTS (Focal Fossa) AMI or the Ubuntu 18.04 LTS (Bionic Beaver) AMI. **To configure an Ubuntu 16.04 LTS AMI to support hibernation** 1. Update the kernel to `4.15.0-1058-aws` or later. ``` [ec2-user ~]$ sudo apt update [ec2-user ~]$ sudo apt install linux-aws-hwe ``` 1. Install the `ec2-hibinit-agent` package from the repositories. ``` [ec2-user ~]$ sudo apt install ec2-hibinit-agent ``` 1. Reboot the instance. ``` [ec2-user ~]$ sudo reboot ``` 1. Confirm that the kernel version is updated to `4.15.0-1058-aws` or later. ``` [ec2-user ~]$ uname -a ``` # Enable hibernation for an Amazon EC2 instance To hibernate an instance, you must first enable it for hibernation while launching the instance. **Important** You can't enable or disable hibernation for an instance after you launch it. **Topics** + [Enable hibernation for On-Demand Instances](#enable-hibernation-for-on-demand-instances) + [Enable hibernation for Spot Instances](#enable-hibernation-for-spot-instances) + [View if an instance is enabled for hibernation](#view-if-instance-is-enabled-for-hibernation) ## Enable hibernation for On-Demand Instances You can enable hibernation for your On-Demand Instances. ------ #### [ Console ] **To enable hibernation for an On-Demand Instance** 1. Follow the procedure to [launch an instance](ec2-launch-instance-wizard.md), but don't launch the instance until you've completed the following steps to enable hibernation. 1. To enable hibernation, configure the following fields in the launch instance wizard: 1. Under **Application and OS Images (Amazon Machine Image)**, select an AMI that supports hibernation. For more information, see [AMIs](hibernating-prerequisites.md#hibernation-prereqs-supported-amis). 1. Under **Instance type**, select a supported instance type. For more information, see [Instance families](hibernating-prerequisites.md#hibernation-prereqs-supported-instance-families). 1. Under **Configure storage**, choose **Advanced** (at the right), and specify the following information for the root volume: + For **Size (GiB)**, enter the EBS root volume size. The volume must be large enough to store the RAM contents and accommodate your expected usage. + For **Volume type**, select a supported EBS volume type: General Purpose SSD (`gp2` and `gp3`) or Provisioned IOPS SSD (`io1` and `io2`). + For **Encrypted**, choose **Yes**. If you enabled encryption by default in this AWS Region, **Yes** is selected. + For **KMS key**, select the encryption key for the volume. If you enabled encryption by default in this AWS Region, the default encryption key is selected. For more information about the prerequisites for the root volume, see [Prerequisites for EC2 instance hibernation](hibernating-prerequisites.md). 1. Expand **Advanced details**, and for **Stop - Hibernate behavior**, choose **Enable**. 1. In the **Summary** panel, review your instance configuration, and then choose **Launch instance**. For more information, see [Launch an EC2 instance using the launch instance wizard in the console](ec2-launch-instance-wizard.md). ------ #### [ AWS CLI ] **To enable hibernation for an On-Demand Instance** Use the [run-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/run-instances.html) command to launch an instance. Specify the EBS root volume parameters using the `--block-device-mappings file://mapping.json` parameter, and enable hibernation using the `--hibernation-options Configured=true` parameter. ``` aws ec2 run-instances \ --image-id ami-0abcdef1234567890 \ --instance-type m5.large \ --block-device-mappings file://mapping.json \ --hibernation-options Configured=true \ --count 1 \ --key-name MyKeyPair ``` Specify the following in `mapping.json`. ``` [ { "DeviceName": "/dev/xvda", "Ebs": { "VolumeSize": 30, "VolumeType": "gp2", "Encrypted": true } } ] ``` The value for `DeviceName` must match the root device name that's associated with the AMI. To find the root device name, use the [describe-images](https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-images.html) command. ``` aws ec2 describe-images --image-id ami-0abcdef1234567890 ``` If you enabled encryption by default in this AWS Region, you can omit `"Encrypted": true`. ------ #### [ PowerShell ] **To enable hibernation for an On-Demand Instance** Use the [New-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/items/New-EC2Instance.html) command to launch an instance. Specify the EBS root volume by first defining the block device mapping, and then adding it to the command using the `-BlockDeviceMappings` parameter. Enable hibernation using the `-HibernationOptions_Configured $true` parameter. ``` $ebs_encrypt = New-Object Amazon.EC2.Model.BlockDeviceMapping $ebs_encrypt.DeviceName = "/dev/xvda" $ebs_encrypt.Ebs = New-Object Amazon.EC2.Model.EbsBlockDevice $ebs_encrypt.Ebs.VolumeSize = 30 $ebs_encrypt.Ebs.VolumeType = "gp2" $ebs_encrypt.Ebs.Encrypted = $true New-EC2Instance ` -ImageId ami-0abcdef1234567890 ` -InstanceType m5.large ` -BlockDeviceMappings $ebs_encrypt ` -HibernationOptions_Configured $true ` -MinCount 1 ` -MaxCount 1 ` -KeyName MyKeyPair ``` The value for `DeviceName` must match the root device name associated with the AMI. To find the root device name, use the [Get-EC2Image](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-EC2Image.html) command. ``` Get-EC2Image -ImageId ami-0abcdef1234567890 ``` If you enabled encryption by default in this AWS Region, you can omit `Encrypted = $true` from the block device mapping. ------ ## Enable hibernation for Spot Instances You can enable hibernation for your Spot Instances. For more information about hibernating a Spot Instance on interruption, see [Spot Instance interruptions](spot-interruptions.md). ------ #### [ Console ] **To enable hibernation for a Spot Instance** 1. Follow the procedure to [request a Spot Instance using the launch instance wizard](using-spot-instances-request.md), but don't launch the instance until you've completed the following steps to enable hibernation. 1. To enable hibernation, configure the following fields in the launch instance wizard: 1. Under **Application and OS Images (Amazon Machine Image)**, select an AMI that supports hibernation. For more information, see [AMIs](hibernating-prerequisites.md#hibernation-prereqs-supported-amis). 1. Under **Instance type**, select a supported instance type. For more information, see [Instance families](hibernating-prerequisites.md#hibernation-prereqs-supported-instance-families). 1. Under **Configure storage**, choose **Advanced** (at the right), and specify the following information for the root volume: + For **Size (GiB)**, enter the EBS root volume size. The volume must be large enough to store the RAM contents and accommodate your expected usage. + For **Volume type**, select a supported EBS volume type: General Purpose SSD (`gp2` and `gp3`) or Provisioned IOPS SSD (`io1` and `io2`). + For **Encrypted**, choose **Yes**. If you enabled encryption by default in this AWS Region, **Yes** is selected. + For **KMS key**, select the encryption key for the volume. If you enabled encryption by default in this AWS Region, the default encryption key is selected. For more information about the prerequisites for the root volume, see [Prerequisites for EC2 instance hibernation](hibernating-prerequisites.md). 1. Expand **Advanced details**, and, in addition to the fields for configuring a Spot Instance, do the following: 1. For **Request type**, choose **Persistent**. 1. For **Interruption behavior**, choose **Hibernate**. Alternatively, for **Stop - Hibernate behavior**, choose **Enable**. Both fields enable hibernation on your Spot Instance. You need only configure one of them. 1. In the **Summary** panel, review your instance configuration, and then choose **Launch instance**. For more information, see [Launch an EC2 instance using the launch instance wizard in the console](ec2-launch-instance-wizard.md). ------ #### [ AWS CLI ] **To enable hibernation for a Spot Instance** Use the [run-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/run-instances.html) command to request a Spot Instance. Specify the EBS root volume parameters using the `--block-device-mappings file://mapping.json` parameter, and enable hibernation using the `--hibernation-options Configured=true` parameter. The Spot request type (`SpotInstanceType`) must be `persistent`. ``` aws ec2 run-instances \ --image-id ami-0abcdef1234567890 \ --instance-type c4.xlarge \ --block-device-mappings file://mapping.json \ --hibernation-options Configured=true \ --count 1 \ --key-name MyKeyPair --instance-market-options { "MarketType":"spot", "SpotOptions":{ "MaxPrice":"1", "SpotInstanceType":"persistent" } } ``` Specify the EBS root volume parameters in `mapping.json` as follows. ``` [ { "DeviceName": "/dev/xvda", "Ebs": { "VolumeSize": 30, "VolumeType": "gp2", "Encrypted": true } } ] ``` The value for `DeviceName` must match the root device name that's associated with the AMI. To find the root device name, use the [describe-images](https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-images.html) command. ``` aws ec2 describe-images --image-id ami-0abcdef1234567890 ``` If you enabled encryption by default in this AWS Region, you can omit `"Encrypted": true`. ------ #### [ PowerShell ] **To enable hibernation for a Spot Instance** Use the [New-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/items/New-EC2Instance.html) command to request a Spot Instance. Specify the EBS root volume by first defining the block device mapping, and then adding it to the command using the `-BlockDeviceMappings` parameter. Enable hibernation using the `-HibernationOptions_Configured $true` parameter. ``` $ebs_encrypt = New-Object Amazon.EC2.Model.BlockDeviceMapping $ebs_encrypt.DeviceName = "/dev/xvda" $ebs_encrypt.Ebs = New-Object Amazon.EC2.Model.EbsBlockDevice $ebs_encrypt.Ebs.VolumeSize = 30 $ebs_encrypt.Ebs.VolumeType = "gp2" $ebs_encrypt.Ebs.Encrypted = $true New-EC2Instance ` -ImageId ami-0abcdef1234567890 ` -InstanceType m5.large ` -BlockDeviceMappings $ebs_encrypt ` -HibernationOptions_Configured $true ` -MinCount 1 ` -MaxCount 1 ` -KeyName MyKeyPair ` -InstanceMarketOption @( MarketType = spot; SpotOptions @{ MaxPrice = 1; SpotInstanceType = persistent} ) ``` The value for `DeviceName` must match the root device name associated with the AMI. To find the root device name, use the [Get-EC2Image](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-EC2Image.html) command. ``` Get-EC2Image -ImageId ami-0abcdef1234567890 ``` If you enabled encryption by default in this AWS Region, you can omit `Encrypted = $true` from the block device mapping. ------ ## View if an instance is enabled for hibernation You can check whether an instance is enabled for hibernation. ------ #### [ Console ] **To view if an instance is enabled for hibernation** 1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/). 1. In the navigation pane, choose **Instances**. 1. Select the instance and, on the **Details** tab, in the **Instance details** section, inspect **Stop-hibernate behavior**. **Enabled** indicates that the instance is enabled for hibernation. ------ #### [ AWS CLI ] **To view if an instance is enabled for hibernation** Use the [describe-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-instances.html) command and specify the `--filters "Name=hibernation-options.configured,Values=true"` parameter to filter instances that are enabled for hibernation. ``` aws ec2 describe-instances \ --filters "Name=hibernation-options.configured,Values=true" ``` The following field in the output indicates that the instance is enabled for hibernation. ``` "HibernationOptions": { "Configured": true } ``` ------ #### [ PowerShell ] **To view if an instance is enabled for hibernation** Use the [Get-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-EC2Instance.html) cmdlet and filter instances that are enabled for hibernation. ``` (Get-EC2Instance ` -Filter @{Name="hibernation-options.configured"; Values="true"}).Instances ``` ------ # Disable KASLR on an instance (Ubuntu only) To run hibernation on a newly launched instance with Ubuntu 16.04 LTS (Xenial Xerus), Ubuntu 18.04 LTS (Bionic Beaver) released with serial number 20190722.1 or later, or Ubuntu 20.04 LTS (Focal Fossa) released with serial number 20210820 or later, we recommend disabling KASLR (Kernel Address Space Layout Randomization). On Ubuntu 16.04 LTS, Ubuntu 18.04 LTS, or Ubuntu 20.04 LTS, KASLR is enabled by default. KASLR is a standard Linux kernel security feature that helps to mitigate exposure to and ramifications of yet-undiscovered memory access vulnerabilities by randomizing the base address value of the kernel. With KASLR enabled, there is a possibility that the instance might not resume after it has been hibernated. To learn more about KASLR, see [Ubuntu Features](https://wiki.ubuntu.com/Security/Features). **To disable KASLR on an instance launched with Ubuntu** 1. Connect to your instance using SSH. For more information, see [Connect to your Linux instance using SSH](connect-to-linux-instance.md). 1. Open the `/etc/default/grub.d/50-cloudimg-settings.cfg` file in your editor of choice. Edit the `GRUB_CMDLINE_LINUX_DEFAULT` line to append the `nokaslr` option to its end, as shown in the following example. ``` GRUB_CMDLINE_LINUX_DEFAULT="console=tty1 console=ttyS0 nvme_core.io_timeout=4294967295 nokaslr" ``` 1. Save the file and exit your editor. 1. Run the following command to rebuild the grub configuration. ``` sudo update-grub ``` 1. Reboot the instance. ``` sudo reboot ``` 1. Run the following command to confirm that `nokaslr` has been added. ``` cat /proc/cmdline ``` The output of the command should include the `nokaslr` option. # Hibernate an Amazon EC2 instance You can initiate hibernation on an On-Demand Instance or Spot Instance if the instance is an EBS-backed instance, is [enabled for hibernation](enabling-hibernation.md), and meets the [hibernation prerequisites](hibernating-prerequisites.md). If an instance cannot hibernate successfully, a normal shutdown occurs. ------ #### [ Console ] **To hibernate an instance** 1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/). 1. In the navigation pane, choose **Instances**. 1. Select an instance, and choose **Instance state**, **Hibernate instance**. If **Hibernate instance** is disabled, the instance is already hibernated or stopped, or it can't be hibernated. For more information, see [Prerequisites for EC2 instance hibernation](hibernating-prerequisites.md). 1. When prompted for confirmation, choose **Hibernate**. It can take a few minutes for the instance to hibernate. The instance state first changes to **Stopping**, and then changes to **Stopped** when the instance has hibernated. ------ #### [ AWS CLI ] **To hibernate an instance** Use the [stop-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/stop-instances.html) command and specify the `--hibernate` parameter. ``` aws ec2 stop-instances \ --instance-ids i-1234567890abcdef0 \ --hibernate ``` ------ #### [ PowerShell ] **To hibernate an instance** Use the [Stop-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2Instance.html) cmdlet. ``` Stop-EC2Instance ` -InstanceId i-1234567890abcdef0 ` -Hibernate $true ``` ------ You can check whether hibernation was initiated on an instance. ------ #### [ Console ] **To view if hibernation was initiated on an instance** 1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/). 1. In the navigation pane, choose **Instances**. 1. Select the instance and, on the **Details** tab, in the **Instance details** section, check the value for **State transition message**. **Client.UserInitiatedHibernate: User initiated hibernate** indicates that you initiated hibernation on the On-Demand Instance or Spot Instance. ------ #### [ AWS CLI ] **To view if hibernation was initiated on an instance** Use the [describe-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-instances.html) command and specify the `state-reason-code` filter to see the instances on which hibernation was initiated. ``` aws ec2 describe-instances \ --filters "Name=state-reason-code,Values=Client.UserInitiatedHibernate" ``` The following field in the output indicates that hibernation was initiated on the On-Demand Instance or Spot Instance. ``` "StateReason": { "Code": "Client.UserInitiatedHibernate" } ``` ------ #### [ PowerShell ] **To view if hibernation was initiated on an instance** Use the [Get-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-EC2Instance.html) cmdlet and specify the `state-reason-code` filter to see the instances on which hibernation was initiated. ``` Get-EC2Instance ` -Filter @{Name="state-reason-code";Value="Client.UserInitiatedHibernate"} ``` ------ # Start a hibernated Amazon EC2 instance Start a hibernated instance by starting it in the same way that you would start a stopped instance. For Spot Instances, if Amazon EC2 hibernated the instance, then only Amazon EC2 can resume it. You can only resume a hibernated Spot Instance if *you* hibernated it. Spot Instances can only be resumed if capacity is available and the Spot price is less than or equal to your specified maximum price. ------ #### [ Console ] **To start a hibernated instance** 1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/). 1. In the navigation pane, choose **Instances**. 1. Select a hibernated instance, and choose **Instance state**, **Start instance**. It can take a few minutes for the instance to enter the `running` state. During this time, the instance [status checks](monitoring-system-instance-status-check.md#types-of-instance-status-checks) show the instance in a failed state until the instance has started. ------ #### [ AWS CLI ] **To start a hibernated instance** Use the [start-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/start-instances.html) command. ``` aws ec2 start-instances --instance-ids i-1234567890abcdef0 ``` ------ #### [ PowerShell ] **To start a hibernated instance** Use the [Start-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2Instance.html) cmdlet. ``` Start-EC2Instance -InstanceId i-1234567890abcdef0 ``` ------ # Troubleshoot Amazon EC2 instance hibernation Use this information to help diagnose and fix issues that you might encounter when hibernating an instance. **Topics** + [Can't hibernate immediately after launch](#hibernate-troubleshooting-1) + [Takes too long to transition from stopping to stopped, and memory state not restored after start](#hibernate-troubleshooting-2) + [Instance "stuck" in the stopping state](#hibernate-troubleshooting-3) + [Can’t start Spot Instance immediately after hibernate](#hibernate-troubleshooting-4) + [Resume Spot Instances failed](#hibernate-troubleshooting-5) ## Can't hibernate immediately after launch If you try to hibernate an instance too quickly after you've launched it, you get an error. You must wait for about two minutes for Linux instances and about five minutes for Windows instances after launch before hibernating. ## Takes too long to transition from stopping to stopped, and memory state not restored after start If it takes a long time for your hibernating instance to transition from the `stopping` state to `stopped`, and if the memory state is not restored after you start, this could indicate that hibernation was not properly configured. **Linux instances** Check the instance system log and look for messages that are related to hibernation. To access the system log, [connect](connect-to-linux-instance.md) to the instance or use the [get-console-output](https://docs.aws.amazon.com/cli/latest/reference/ec2/get-console-output.html) command. Find the log lines from the `hibinit-agent`. If the log lines indicate a failure or the log lines are missing, there was most likely a failure configuring hibernation at launch. For example, the following message indicates that the instance root volume is not large enough: `hibinit-agent: Insufficient disk space. Cannot create setup for hibernation. Please allocate a larger root device.` If the last log line from the `hibinit-agent` is `hibinit-agent: Running: swapoff /swap`, hibernation was successfully configured. If you do not see any logs from these processes, your AMI might not support hibernation. For information about supported AMIs, see [Prerequisites for EC2 instance hibernation](hibernating-prerequisites.md). If you used your own Linux AMI, make sure that you followed the instructions for [Configure a Linux AMI to support hibernation](hibernation-enabled-AMI.md). **Windows Server 2016 and later** Check the EC2 launch log and look for messages that are related to hibernation. To access the EC2 launch log, [connect](connecting_to_windows_instance.md) to the instance and open the `C:\ProgramData\Amazon\EC2-Windows\Launch\Log\Ec2Launch.log` file in a text editor. If you're using EC2Launch v2, open `C:\ProgramData\Amazon\EC2Launch\log\agent.log`. **Note** By default, Windows hides files and folders under `C:\ProgramData`. To view EC2 Launch directories and files, enter the path in Windows Explorer or change the folder properties to show hidden files and folders. Find the log lines for hibernation. If the log lines indicate a failure or the log lines are missing, there was most likely a failure configuring hibernation at launch. For example, the following message indicates that hibernation failed to configure: `Message: Failed to enable hibernation.` If the error message includes decimal ASCII values, you can convert the ASCII values to plain text in order to read the full error message. If the log line contains `HibernationEnabled: true`, hibernation was successfully configured. **Windows Server 2012 R2 and earlier** Check the EC2 config log and look for messages that are related to hibernation. To access the EC2 config log, [connect](connecting_to_windows_instance.md) to the instance and open the `C:\Program Files\Amazon\Ec2ConfigService\Logs\Ec2ConfigLog.txt` file in a text editor. Find the log lines for `SetHibernateOnSleep`. If the log lines indicate a failure or the log lines are missing, there was most likely a failure configuring hibernation at launch. For example, the following message indicates that the instance root volume is not large enough: `SetHibernateOnSleep: Failed to enable hibernation: Hibernation failed with the following error: There is not enough space on the disk.` If the log line is `SetHibernateOnSleep: HibernationEnabled: true`, hibernation was successfully configured. **Windows instance size** If you’re using a T3 or T3a Windows instance with less than 1 GiB of RAM, try increasing the size of the instance to one that has at least 1 GiB of RAM. ## Instance "stuck" in the stopping state If you hibernated your instance and it appears "stuck" in the `stopping` state, you can forcibly stop it. For more information, see [Troubleshoot Amazon EC2 instance stop issues](TroubleshootingInstancesStopping.md). ## Can’t start Spot Instance immediately after hibernate If you try to start a Spot Instance within two minutes of hibernating it, you might get the following error: `You failed to start the Spot Instance because the associated Spot Instance request is not in an appropriate state to support start.` Wait for about two minutes for Linux instances and about five minutes for Windows instances and then retry starting the instance. ## Resume Spot Instances failed If your Spot Instance was hibernated successfully but failed to resume, and instead rebooted (a fresh restart where the hibernated state is not retained), it might be because the user data contained the following script: ``` /usr/bin/enable-ec2-spot-hibernation ``` Remove this script from the **User data** field in the launch template, and then request a new Spot Instance. Note that even if the instance failed to resume, without the hibernated state preserved, the instance can still be started in the same way as starting from the `stopped` state.