# Programmatic modifications made to VMs by VM Import/Export
<a name="import-modify-vm"></a>

When importing a VM using the `ImportImage` API, AWS modifies the file system and adds drivers to make the imported VM bootable. When writing a modified file, AWS retains the original file at the same location under a new name. The following actions may occur:

**General**
+ For parity with images provided by AWS, the AWS Systems Manager client is installed on the VM.

**Windows**
+ Modifying registry settings to make the VM bootable.

**Linux**
+ Installing Citrix PV drivers either directly in OS or modify initrd/initramfs to contain them.
+ Modifying network scripts to replace static IPs with dynamic IPs.
+ Modifying `/etc/fstab`, commenting out invalid entries and replacing device names with UUIDs. If no matching UUID can be found for a device, the `nofail` option is added to the device description. You must correct the device naming and remove `nofail` after import. As a best practice when preparing your VMs for import, we recommend that you specify your VM disk devices by UUID rather than device name.

  Entries in `/etc/fstab` that contain non-standard file system types (cifs, smbfs, vboxsf, sshfs, etc.) are disabled.
+ Modifying grub bootloader settings such as the default entry and timeout.

## Import VM without modifications
<a name="import-without-modifications"></a>

If you need to import a VM without programmatic modifications, we recommend that you follow these steps instead of using `ImportImage`.

**Important**  
If you use this process, AWS does not do any post-import validations to ensure that the image is bootable. It is your responsibility to ensure that you properly prepare your VM for exporting.

**To import a VM without modifications**

1. Prepare your VM for export. For more information, see [Configurations to export VMs from your virtualization environment](prepare-vm-image.md).

1. Export the boot disk for your VM in one of the following file formats: VHD/VHDX, VMDK, or raw. For more information, refer to the documentation for your virtualization environment.

1. Use the [ put-object](https://docs.aws.amazon.com/cli/latest/reference/s3api/put-object.html) command to upload the exported boot disk file to an Amazon S3 bucket in the Region where you want to create the image.

1. Use the [ import-snapshot](https://docs.aws.amazon.com/cli/latest/reference/ec2/import-snapshot.html) command to import the boot disk as a snapshot. For more information about importing a snapshot, see [Import a disk as an EBS snapshot using VM Import/Export](vmimport-import-snapshot.md).
**Note**  
You can monitor the progress of the import snapshot task using the [ describe-import-snapshot-tasks](https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-import-snapshot-tasks.html) command.

   Make a note of the snapshot ID returned by the command. You'll need it for the next step.

1. Use the [ register-image](https://docs.aws.amazon.com/cli/latest/reference/ec2/register-image.html) command to register a new AMI, and specify the snapshot from the previous step as the root device volume.

   Make a note of the image ID returned by the command. You'll need it for the next step.

1. After the AMI reaches the `available` state, you can use it to launch instances.