Launch an instance

You can launch an instance in UEFI or Legacy BIOS boot mode.

Limitations

UEFI boot is not supported in Local Zones, Wavelength Zones, or with AWS Outposts.

Considerations

Consider the following when launching an instance:

• The boot mode of the instance is determined by the configuration of the AMI, the operating system contained in it, and the instance type, illustrated by the following image:

  

  The following table shows that the boot mode of an instance (indicated by the Resulting instance boot mode column) is determined by a combination of the boot mode parameter of the AMI (column 1), the boot mode configuration of the operating system contained in the AMI (column 2), and the boot mode support of the instance type (column 3).

  AMI boot mode parameter	Operating system boot mode configuration	Instance type boot mode support	Resulting instance boot mode
  UEFI	UEFI	UEFI	UEFI
  Legacy BIOS	Legacy BIOS	Legacy BIOS	Legacy BIOS
  UEFI Preferred	UEFI	UEFI	UEFI
  UEFI Preferred	UEFI	UEFI and Legacy BIOS	UEFI
  UEFI Preferred	Legacy BIOS	Legacy BIOS	Legacy BIOS
  UEFI Preferred	Legacy BIOS	UEFI and Legacy BIOS	Legacy BIOS
  No boot mode specified - ARM	UEFI	UEFI	UEFI
  No boot mode specified - x86	Legacy BIOS	UEFI and Legacy BIOS	Legacy BIOS

• Default boot modes:

  • Graviton instance types: UEFI

  • Intel and AMD instance types: Legacy BIOS

• Intel and AMD instance types that support UEFI, in addition to Legacy BIOS:

  • All instances built on the AWS Nitro System, except: bare metal instances, DL1, G4ad, P4, u-3tb1, u-6tb1, u-9tb1, u-12tb1, and VT1

   

  To see the available instance types that support UEFI in a specific Region

  The available instance types vary by AWS Region. To see the available instance types that support UEFI in a Region, use the describe-instance-types command with the --region parameter. If you omit the --region parameter, your default Region is used in the request. Include the --filters parameter to scope the results to the instance types that support UEFI and the --query parameter to scope the output to the value of InstanceType.

  aws ec2 describe-instance-types --filters Name=supported-boot-mode,Values=uefi --query "InstanceTypes[*].[InstanceType]" --output text | sort

  Example output

  a1.2xlarge
  a1.4xlarge
  a1.large
  a1.medium
  ...

   

  To see the available instance types that support UEFI Secure Boot and persist non-volatile variables in a specific Region

  Currently, bare metal instances do not support UEFI Secure Boot and non-volatile variables. Use the describe-instance-types command as described in the preceding example, but filter out the bare metal instances by including the Name=hypervisor,Values=nitro filter. For information about UEFI Secure Boot, see UEFI Secure Boot.

  aws ec2 describe-instance-types --filters Name=supported-boot-mode,Values=uefi Name=hypervisor,Values=nitro --query "InstanceTypes[*].[InstanceType]" --output text | sort

Requirements for launching an instance on UEFI

To launch an instance in UEFI boot mode, you must select an instance type that supports UEFI, and configure the AMI and the operating system for UEFI, as follows:

Instance type

When launching an instance, you must select an instance type that supports UEFI. For more information, see Determine the supported boot modes of an instance type.

AMI

When launching an instance, you must select an AMI that is configured for UEFI. The AMI must be configured as follows:

• Operating system – The operating system contained in the AMI must be configured to use UEFI; otherwise, the instance launch will fail. For more information, see Determine the boot mode of the operating system.

• AMI boot mode parameter – The boot mode parameter of the AMI must be set to uefi or uefi-preferred. For more information, see Determine the boot mode parameter of an AMI.

The following Windows AMIs support UEFI:

• TPM-Windows_Server-2022-English-Full-Base

• TPM-Windows_Server-2022-English-Core-Base

• TPM-Windows_Server-2019-English-Full-Base

• TPM-Windows_Server-2019-English-Core-Base

• TPM-Windows_Server-2016-English-Full-Base

• TPM-Windows_Server-2016-English-Core-Base

For information about Linux AMIs, see Requirements for launching an instance on UEFI in the Amazon EC2 User Guide for Linux Instances.