# Enable enhanced networking on your instance The procedure that you use depends on the operating system of the instance. ## Amazon Linux The AMIs for Amazon Linux include the kernel driver required for enhanced networking with ENA installed and have ENA support enabled. Therefore, if you launch an instance with an HVM version of Amazon Linux on a supported instance type, enhanced networking is already enabled for your instance. For more information, see [Test whether enhanced networking is enabled](test-enhanced-networking-ena.md). ## Ubuntu The latest Ubuntu HVM AMIs include the kernel driver required for enhanced networking with ENA installed and have ENA support enabled. Therefore, if you launch an instance with the latest Ubuntu HVM AMI on a supported instance type, enhanced networking is already enabled for your instance. For more information, see [Test whether enhanced networking is enabled](test-enhanced-networking-ena.md). If you launched your instance using an older AMI and it does not have enhanced networking enabled already, you can install the `linux-aws` kernel package to get the latest enhanced networking drivers and update the required attribute. **To install the `linux-aws` kernel package (Ubuntu 16.04 or later)** Ubuntu 16.04 and 18.04 ship with the Ubuntu custom kernel (`linux-aws` kernel package). To use a different kernel, contact [Support](https://console.aws.amazon.com/support). **To install the `linux-aws` kernel package (Ubuntu Trusty 14.04)** 1. Connect to your instance. 1. Update the package cache and packages. ``` ubuntu:~$ sudo apt-get update && sudo apt-get upgrade -y linux-aws ``` **Important** If during the update process you are prompted to install `grub`, use `/dev/xvda` to install `grub` onto, and then choose to keep the current version of `/boot/grub/menu.lst`. 1. [EBS-backed instance] From your local computer, stop the instance using the Amazon EC2 console or one of the following commands: [https://docs.aws.amazon.com/cli/latest/reference/ec2/stop-instances.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/stop-instances.html) (AWS CLI) or [https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2Instance.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2Instance.html) (AWS Tools for Windows PowerShell). [Instance store-backed instance] You can't stop the instance to modify the attribute. Instead, proceed to this procedure: [To enable enhanced networking on Ubuntu (instance store-backed instances)](#enhanced-networking-ena-instance-store-ubuntu). 1. From your local computer, enable the enhanced networking attribute using one of the following commands: + [https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html) (AWS CLI) ``` aws ec2 modify-instance-attribute --instance-id i-1234567890abcdef0 --ena-support ``` + [https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html) (Tools for Windows PowerShell) ``` Edit-EC2InstanceAttribute -InstanceId i-1234567890abcdef0 -EnaSupport $true ``` 1. (Optional) Create an AMI from the instance, as described in [Create an Amazon EBS-backed AMI](creating-an-ami-ebs.md). The AMI inherits the enhanced networking `enaSupport` attribute from the instance. Therefore, you can use this AMI to launch another instance with enhanced networking enabled by default. 1. From your local computer, start the instance using the Amazon EC2 console or one of the following commands: [https://docs.aws.amazon.com/cli/latest/reference/ec2/start-instances.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/start-instances.html) (AWS CLI) or [https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2Instance.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2Instance.html) (AWS Tools for Windows PowerShell). **To enable enhanced networking on Ubuntu (instance store-backed instances)** Follow the previous procedure until the step where you stop the instance. Create a new AMI as described in [Create an Amazon S3-backed AMI](creating-an-ami-instance-store.md), making sure to enable the enhanced networking attribute when you register the AMI. + [https://docs.aws.amazon.com/cli/latest/reference/ec2/register-image.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/register-image.html) (AWS CLI) ``` aws ec2 register-image --ena-support ... ``` + [https://docs.aws.amazon.com/powershell/latest/reference/items/Register-EC2Image.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Register-EC2Image.html) (AWS Tools for Windows PowerShell) ``` Register-EC2Image -EnaSupport $true ... ``` ## RHEL, SUSE, CentOS The latest AMIs for Red Hat Enterprise Linux, SUSE Linux Enterprise Server, and CentOS include the kernel driver required for enhanced networking with ENA and have ENA support enabled. Therefore, if you launch an instance with the latest AMI on a supported instance type, enhanced networking is already enabled for your instance. For more information, see [Test whether enhanced networking is enabled](test-enhanced-networking-ena.md). The following procedure provides the general steps for enabling enhanced networking on a Linux distribution other than Amazon Linux AMI or Ubuntu. For more information, such as detailed syntax for commands, file locations, or package and tool support, see the documentation for your Linux distribution. **To enable enhanced networking on Linux** 1. Connect to your instance. 1. Clone the source code for the `ena` kernel driver on your instance from GitHub at [https://github.com/amzn/amzn-drivers](https://github.com/amzn/amzn-drivers). (SUSE Linux Enterprise Server 12 SP2 and later include ENA 2.02 by default, so you are not required to download and compile the ENA driver. For SUSE Linux Enterprise Server 12 SP2 and later, you should file a request to add the driver version you want to the stock kernel). ``` git clone https://github.com/amzn/amzn-drivers ``` 1. Compile and install the `ena` kernel driver on your instance. These steps depend on the Linux distribution. For more information about compiling the kernel driver on Red Hat Enterprise Linux, see [How do I install the latest ENS driver for enhanced network support on an Amazon EC2 instance that runs RHEL?](https://repost.aws/knowledge-center/install-ena-driver-rhel-ec2) 1. Run the **sudo depmod** command to update kernel driver dependencies. 1. Update `initramfs` on your instance to ensure that the new kernel driver loads at boot time. For example, if your distribution supports **dracut**, you can use the following command. ``` dracut -f -v ``` 1. Determine if your system uses predictable network interface names by default. Systems that use **systemd** or **udev** versions 197 or greater can rename Ethernet devices and they do not guarantee that a single network interface will be named `eth0`. This behavior can cause problems connecting to your instance. For more information and to see other configuration options, see [Predictable Network Interface Names](https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/) on the freedesktop.org website. 1. You can check the **systemd** or **udev** versions on RPM-based systems with the following command. ``` rpm -qa | grep -e '^systemd-[0-9]\+\|^udev-[0-9]\+' systemd-208-11.el7_0.2.x86_64 ``` In the above Red Hat Enterprise Linux 7 example, the **systemd** version is 208, so predictable network interface names must be disabled. 1. Disable predictable network interface names by adding the `net.ifnames=0` option to the `GRUB_CMDLINE_LINUX` line in `/etc/default/grub`. ``` sudo sed -i '/^GRUB\_CMDLINE\_LINUX/s/\"$/\ net\.ifnames\=0\"/' /etc/default/grub ``` 1. Rebuild the grub configuration file. ``` sudo grub2-mkconfig -o /boot/grub2/grub.cfg ``` 1. [EBS-backed instance] From your local computer, stop the instance using the Amazon EC2 console or one of the following commands: [https://docs.aws.amazon.com/cli/latest/reference/ec2/stop-instances.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/stop-instances.html) (AWS CLI), [https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2Instance.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2Instance.html) (AWS Tools for Windows PowerShell). [Instance store-backed instance] You can't stop the instance to modify the attribute. Instead, proceed to this procedure: [To enable enhanced networking on Linux (instance store–backed instances)](#other-linux-enhanced-networking-ena-instance-store). 1. From your local computer, enable the enhanced networking `enaSupport` attribute using one of the following commands: + [https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html) (AWS CLI) ``` aws ec2 modify-instance-attribute --instance-id i-1234567890abcdef0 --ena-support ``` + [https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html) (Tools for Windows PowerShell) ``` Edit-EC2InstanceAttribute -InstanceId i-1234567890abcdef0 -EnaSupport $true ``` 1. (Optional) Create an AMI from the instance, as described in [Create an Amazon EBS-backed AMI](creating-an-ami-ebs.md). The AMI inherits the enhanced networking `enaSupport` attribute from the instance. Therefore, you can use this AMI to launch another instance with enhanced networking enabled by default. If your instance operating system contains an `/etc/udev/rules.d/70-persistent-net.rules` file, you must delete it before creating the AMI. This file contains the MAC address for the Ethernet adapter of the original instance. If another instance boots with this file, the operating system will be unable to find the device and `eth0` might fail, causing boot issues. This file is regenerated at the next boot cycle, and any instances launched from the AMI create their own version of the file. 1. From your local computer, start the instance using the Amazon EC2 console or one of the following commands: [https://docs.aws.amazon.com/cli/latest/reference/ec2/start-instances.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/start-instances.html) (AWS CLI) or [https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2Instance.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2Instance.html) (AWS Tools for Windows PowerShell). 1. (Optional) Connect to your instance and verify that the kernel driver is installed. If you are unable to connect to your instance after enabling enhanced networking, see [Troubleshoot the ENA kernel driver on Linux](troubleshooting-ena.md). **To enable enhanced networking on Linux (instance store–backed instances)** Follow the previous procedure until the step where you stop the instance. Create a new AMI as described in [Create an Amazon S3-backed AMI](creating-an-ami-instance-store.md), making sure to enable the enhanced networking attribute when you register the AMI. + [https://docs.aws.amazon.com/cli/latest/reference/ec2/register-image.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/register-image.html) (AWS CLI) ``` aws ec2 register-image --ena-support ... ``` + [https://docs.aws.amazon.com/powershell/latest/reference/items/Register-EC2Image.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Register-EC2Image.html) (AWS Tools for Windows PowerShell) ``` Register-EC2Image -EnaSupport ... ``` ## Ubuntu with DKMS This method is for testing and feedback purposes only. It is not intended for use with production deployments. For production deployments, see [Ubuntu](#enhanced-networking-ena-ubuntu). **Important** Using DKMS voids the support agreement for your subscription. It should not be used for production deployments. **To enable enhanced networking with ENA on Ubuntu (EBS-backed instances)** 1. Follow steps 1 and 2 in [Ubuntu](#enhanced-networking-ena-ubuntu). 1. Install the `build-essential` packages to compile the kernel driver and the `dkms` package so that your `ena` kernel driver is rebuilt every time your kernel is updated. ``` ubuntu:~$ sudo apt-get install -y build-essential dkms ``` 1. Clone the source for the `ena` kernel driver on your instance from GitHub at [https://github.com/amzn/amzn-drivers](https://github.com/amzn/amzn-drivers). ``` ubuntu:~$ git clone https://github.com/amzn/amzn-drivers ``` 1. Move the `amzn-drivers` package to the `/usr/src/` directory so DKMS can find it and build it for each kernel update. Append the version number (you can find the current version number in the release notes) of the source code to the directory name. For example, version `1.0.0` is shown in the following example. ``` ubuntu:~$ sudo mv amzn-drivers /usr/src/amzn-drivers-1.0.0 ``` 1. Create the DKMS configuration file with the following values, substituting your version of `ena`. Create the file. ``` ubuntu:~$ sudo touch /usr/src/amzn-drivers-1.0.0/dkms.conf ``` Edit the file and add the following values. ``` ubuntu:~$ sudo vim /usr/src/amzn-drivers-1.0.0/dkms.conf PACKAGE_NAME="ena" PACKAGE_VERSION="1.0.0" CLEAN="make -C kernel/linux/ena clean" MAKE="make -C kernel/linux/ena/ BUILD_KERNEL=${kernelver}" BUILT_MODULE_NAME[0]="ena" BUILT_MODULE_LOCATION="kernel/linux/ena" DEST_MODULE_LOCATION[0]="/updates" DEST_MODULE_NAME[0]="ena" AUTOINSTALL="yes" ``` 1. Add, build, and install the `ena` kernel driver on your instance using DKMS. Add the kernel driver to DKMS. ``` ubuntu:~$ sudo dkms add -m amzn-drivers -v 1.0.0 ``` Build the kernel driver using the **dkms** command. ``` ubuntu:~$ sudo dkms build -m amzn-drivers -v 1.0.0 ``` Install the kernel driver using **dkms**. ``` ubuntu:~$ sudo dkms install -m amzn-drivers -v 1.0.0 ``` 1. Rebuild `initramfs` so the correct kernel driver is loaded at boot time. ``` ubuntu:~$ sudo update-initramfs -u -k all ``` 1. Verify that the `ena` kernel driver is installed using the modinfo ena command from [Test whether enhanced networking is enabled](test-enhanced-networking-ena.md). ``` ubuntu:~$ modinfo ena filename: /lib/modules/3.13.0-74-generic/updates/dkms/ena.ko version: 1.0.0 license: GPL description: Elastic Network Adapter (ENA) author: Amazon.com, Inc. or its affiliates srcversion: 9693C876C54CA64AE48F0CA alias: pci:v00001D0Fd0000EC21sv*sd*bc*sc*i* alias: pci:v00001D0Fd0000EC20sv*sd*bc*sc*i* alias: pci:v00001D0Fd00001EC2sv*sd*bc*sc*i* alias: pci:v00001D0Fd00000EC2sv*sd*bc*sc*i* depends: vermagic: 3.13.0-74-generic SMP mod_unload modversions parm: debug:Debug level (0=none,...,16=all) (int) parm: push_mode:Descriptor / header push mode (0=automatic,1=disable,3=enable) 0 - Automatically choose according to device capability (default) 1 - Don't push anything to device memory 3 - Push descriptors and header buffer to device memory (int) parm: enable_wd:Enable keepalive watchdog (0=disable,1=enable,default=1) (int) parm: enable_missing_tx_detection:Enable missing Tx completions. (default=1) (int) parm: numa_node_override_array:Numa node override map (array of int) parm: numa_node_override:Enable/Disable numa node override (0=disable) (int) ``` 1. Continue with Step 3 in [Ubuntu](#enhanced-networking-ena-ubuntu). ## Enable enhanced networking on Windows If you launched your instance and it does not have enhanced networking enabled already, you must download and install the required network adapter driver on your instance, and then set the `enaSupport` instance attribute to activate enhanced networking. **To enable enhanced networking** 1. Connect to your instance and log in as the local administrator. 1. [Windows Server 2016 and 2019 only] Run the following EC2Launch PowerShell script to configure the instance after the driver is installed. ``` PS C:\> C:\ProgramData\Amazon\EC2-Windows\Launch\Scripts\InitializeInstance.ps1 -Schedule ``` 1. From the instance, install the driver as follows: 1. [Download](https://s3.amazonaws.com/ec2-windows-drivers-downloads/ENA/Latest/AwsEnaNetworkDriver.zip) the latest driver to the instance. 1. Extract the zip archive. 1. Install the driver by running the `install.ps1` PowerShell script. **Note** If you get an execution policy error, set the policy to `Unrestricted` (by default it is set to `Restricted` or `RemoteSigned`). In a command line, run `Set-ExecutionPolicy -ExecutionPolicy Unrestricted`, and then run the `install.ps1` PowerShell script again. 1. From your local computer, stop the instance using the Amazon EC2 console or one of the following commands: [https://docs.aws.amazon.com/cli/latest/reference/ec2/stop-instances.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/stop-instances.html) (AWS CLI) or [https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2Instance.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Stop-EC2Instance.html) (AWS Tools for Windows PowerShell). 1. Enable ENA support on your instance as follows: 1. From your local computer, check the EC2 instance ENA support attribute on your instance by running one of the following commands. If the attribute is not enabled, the output will be "[]" or blank. `EnaSupport` is set to `false` by default. + [https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-instances.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/describe-instances.html) (AWS CLI) ``` aws ec2 describe-instances --instance-ids i-1234567890abcdef0 --query "Reservations[].Instances[].EnaSupport" ``` + [https://docs.aws.amazon.com/powershell/latest/reference/items/Get-EC2Instance.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Get-EC2Instance.html) (Tools for Windows PowerShell) ``` (Get-EC2Instance -InstanceId i-1234567890abcdef0).Instances.EnaSupport ``` 1. To enable ENA support, run one of the following commands: + [https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html) (AWS CLI) ``` aws ec2 modify-instance-attribute --instance-id i-1234567890abcdef0 --ena-support ``` + [https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html) (AWS Tools for Windows PowerShell) ``` Edit-EC2InstanceAttribute -InstanceId i-1234567890abcdef0 -EnaSupport $true ``` If you encounter problems when you restart the instance, you can also disable ENA support using one of the following commands: + [https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-instance-attribute.html) (AWS CLI) ``` aws ec2 modify-instance-attribute --instance-id i-1234567890abcdef0 --no-ena-support ``` + [https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2InstanceAttribute.html) (AWS Tools for Windows PowerShell) ``` Edit-EC2InstanceAttribute -InstanceId i-1234567890abcdef0 -EnaSupport $false ``` 1. Verify that the attribute has been set to `true` using **describe-instances** or **Get-EC2Instance** as shown previously. You should now see the following output: ``` [ true ] ``` 1. From your local computer, start the instance using the Amazon EC2 console or one of the following commands: [https://docs.aws.amazon.com/cli/latest/reference/ec2/start-instances.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/start-instances.html) (AWS CLI) or [https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2Instance.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Start-EC2Instance.html) (AWS Tools for Windows PowerShell). 1. On the instance, validate that the ENA driver is installed and enabled as follows: 1. Right-click the network icon and choose **Open Network and Sharing Center**. 1. Choose the Ethernet adapter (for example, **Ethernet 2**). 1. Choose **Details**. For **Network Connection Details**, check that **Description** is **Amazon Elastic Network Adapter**. 1. (Optional) Create an AMI from the instance. The AMI inherits the `enaSupport` attribute from the instance. Therefore, you can use this AMI to launch another instance with ENA enabled by default.