Track ENA Windows driver version releases - Amazon Elastic Compute Cloud
ENA Windows driver version historySubscribe to driver release notifications

Track ENA Windows driver version releases

Windows AMIs include the ENA Windows driver to enable enhanced networking.

For Windows Server versions 2016 and above, we recommend that you use the latest driver version. For earlier versions of Windows Server, refer to the following table to determine which ENA driver version to use.

Windows Server version ENA driver version
Windows Server 2012 R2 2.6.0 and earlier
Windows Server 2012 2.6.0 and earlier
Windows Server 2008 R2 2.2.3 and earlier

ENA Windows driver version history

The following table summarizes the changes for each release.

Driver version Details Release date

2.8.0

Bug Fixes

  • Fixed a race condition in the complete flow of egress network buffer list (NBL) processing, which could lead to memory corruption caused by attempting to release an NBL that was already released.

  • Fixed misdetection of L3 protocol when disabling all LSO and checksum offloads that could lead to unexpected behavior.

 September 30, 2024

2.7.0

New Features

  • Removed support for Windows Server 2012 (Windows 8) and Windows Server 2012 R2 (Windows 8.1). These operating system versions have reached the end of support from AWS. Driver install will fail on Windows Server 2012 and earlier.

  • Added support for offloading IPv6 Tx checksum calculation to the device.

  • Added wide Low Latency Queuing (LLQ) support. This is dynamically enabled based on device recommendation. You can override this setting with the new "WideLLQ" registry key.

  • Added reporting for packet drops resulting from Rx overrun, which indicates insufficient space in the Rx ring for incoming packets.

  • Added support for suboptimal configuration notifications from the device. See event ID 59000 in the Windows event viewer.

Bug Fixes

  • Avoid unnecessary device reset caused by Tx packets with headers that exceed the maximum Low Latency Queuing (LLQ) header size.

 May 1, 2024

2.6.0

New Features

  • Adds the following network performance metrics for instance types that support ENA Express.

    • ena_srd_mode

    • ena_srd_tx_pkts

    • ena_srd_eligible_tx_pkts

    • ena_srd_rx_pkts

    • ena_srd_resource_utilization

  • Adds conntrack_allowance_available network performance metric for Nitro based instance types.

  • Adds new adapter reset reason due to detection of RX data corruption.

  • Updates driver logging infrastructure.

Bug Fixes

  • Prevents adapter reset in the event that CPU starvation causes a network performance metrics update to fail.

  • Prevents false detection of an interruption to the device heartbeat.

  • Fixes driver installation script to support downgrade operation.

  • Fixes the receive error count statistic.

 June 20, 2023

2.5.0
Announcement

ENA Windows driver version 2.5.0 has been rolled back due to failure to initialize on the Windows domain controller. Windows Client and Windows Server are unaffected.

 February 17, 2023

2.4.0

New Features

  • Adds support for Windows Server 2022.

  • Removes support for Windows Server 2008 R2.

  • Sets Low Latency Queuing (LLQ) to always on to improve performance on sixth generation Amazon EC2 instances.

Bug Fix

  • Fixes a failure to publish network performance metrics to the Performance Counters for Windows (PCW) system.

  • Fixes a memory leak during the registry key reading operation.

  • Prevents an infinite reset loop in the event of an unrecoverable error during the adapter reset process.

 April 28, 2022

2.2.4
Announcement

ENA Windows driver version 2.2.4 has been rolled back due to potential performance degradation on the sixth generation EC2 instances. We recommend that you downgrade the driver, using one of the following methods:

  • Install the previous version

    1. Download the previous version package from the link in this table (version 2.2.3).

    2. Run the install.ps1 PowerShell installation script.

    For more details for pre- and post-installation steps see Enable enhanced networking on Windows.

    Use Amazon EC2 Systems Manager for a bulk update

    • Perform a bulk update via SSM document AWS-ConfigureAWSPackage, with the following parameters:

      • Name: AwsEnaNetworkDriver

      • Version: 2.2.3

 October 26, 2021

2.2.3

New Feature

  • Adds support for new Nitro cards with up to 400 Gbps instance networking.

Bug Fix

  • Fixes race condition between system time change and system time query by the ENA driver, which causes false-positive detection of HW unresponsiveness.

Windows ENA driver version 2.2.3 is the final version that supports Windows Server 2008 R2. Currently available instance types that use ENA will continue to be supported on Windows Server 2008 R2, and the drivers are available by download. No future instance types will support Windows Server 2008 R2, and you cannot launch, import, or migrate Windows Server 2008 R2 images to future instance types.

March 25, 2021

2.2.2

New Feature

  • Adds support to query network adapter performance metrics with CloudWatch and the Performance Counters for Windows consumers.

Bug Fix

  • Fixes performance issues on bare metal instances.

 December 21, 2020

2.2.1

New Feature

  • Adds a method to allow the host to query the Elastic Network Adapter for network performance metrics.

 October 1, 2020

2.2.0

New Features

  • Adds support for next generation hardware types.

  • Improves instance start time after resuming from stop-hibernate, and eliminates false positive ENA error messages.

Performance Optimizations

  • Optimizes processing of inbound traffic.

  • Improves shared memory management in low resource environment.

Bug Fix

  • Avoids system crash upon ENA device removal in rare scenario where driver fails to reset.

 August 12, 2020

2.1.5

Bug Fix

  • Fixes occasional network adapter initialization failure on bare metal instances.

 June 23, 2020

2.1.4

Bug Fixes

  • Prevent connectivity issues caused by corrupted LSO packet metadata arriving from the network stack.

  • Prevent system crash caused by a rare race condition that results in accessing an already released packet memory.

 November 25, 2019

2.1.2

New Feature

  • Added support for vendor ID report to allow OS to generate MAC-based UUIDs.

Bug Fixes

  • Improved DHCP network configuration performance during initialization.

  • Properly calculate L4 checksum on inbound IPv6 traffic when the maximum transmission unit (MTU) exceeds 4K.

  • General improvements to driver stability and minor bug fixes.

 November 4, 2019

2.1.1

 Bug Fixes

  • Prevent drops of highly fragmented TCP LSO packets arriving from operating system.

  • Properly handle Encapsulating Security Payload (ESP) protocol within the IPSec in IPv6 networks.

 September 16, 2019

2.1.0

 ENA Windows driver v2.1 introduces new ENA device capabilities, provides a performance boost, adds new features, and includes multiple stability improvements.

  • New features

    • Use standardized Windows registry key for Jumbo frames configuration.

    • Allow VLAN ID setting via the ENA driver properties GUI.

    • Improved Recovery flows

      • Improved failure identification mechanism.

      • Added support for tunable recovery parameters.

    • Support up to 32 I/O queues for newer EC2 instances that have more than 8 vCPUs.

    • ~90% reduction of driver memory footprint.

  • Performance optimizations

    • Reduced transmit path latency.

    • Support for receive checksum offload.

    • Performance optimization for heavily loaded system (optimized usage of locking mechanisms).

    • Further enhancements to reduce CPU utilization and improve system responsiveness under load.

  • Bug Fixes

    • Fix crash due to invalid parsing of non-contiguous Tx headers.

    • Fix driver v1.5 crash during the elastic network interface detach on Bare Metal instances.

    • Fix LSO pseudo-header checksum calculation error over IPv6.

    • Fix potential memory resource leak upon initialization failure.

    • Disable TCP/UDP checksum offload for IPv4 fragments.

    • Fix for VLAN configuration. VLAN was incorrectly disabled when only VLAN priority should have been disabled.

    • Enable correct parsing of custom driver messages by the event viewer.

    • Fix failure to initialize driver due to invalid timestamp handling.

    • Fix race condition between data processing and ENA device disabling.

 July 1, 2019

1.5.0

  • Improved stability and performance fixes.

  • Receive Buffers can now be configured up to a value of 8192 in Advanced Properties of the ENA NIC.

  • Default Receive Buffers of 1k.

 October 4, 2018

1.2.3

Includes reliability fixes and unifies support for Windows Server 2008 R2 through Windows Server 2016.

 February 13, 2018

1.0.8

The initial release. Included in AMIs for Windows Server 2008 R2, Windows Server 2012 RTM, Windows Server 2012 R2, and Windows Server 2016.

 July 2016

Subscribe to ENA Windows driver release notifications from Amazon SNS

Amazon SNS can notify you when new versions of EC2 Windows Drivers are released. Use the following procedure to subscribe to these notifications.

Subscribe to EC2 notifications

  1. Open the Amazon SNS console at https://console.aws.amazon.com/sns/v3/home.

  2. In the navigation bar, change the Region to US East (N. Virginia), if necessary. You must select this Region because the SNS notifications that you are subscribing to are in this Region.

  3. In the navigation pane, choose Subscriptions.

  4. Choose Create subscription.

  5. In the Create subscription dialog box, do the following:

    1. For TopicARN, copy the following Amazon Resource Name (ARN):

      arn:aws:sns:us-east-1:801119661308:ec2-windows-drivers

    2. For Protocol, choose Email.

    3. For Endpoint, enter an email address where you want notifications sent.

    4. Choose Create subscription.

  6. You'll receive a confirmation email. Open the email and follow the directions to complete your subscription.

Whenever new EC2 Windows drivers are released, we send notifications to subscribers. If you no longer want to receive these notifications, use the following procedure to unsubscribe.

Unsubscribe from Amazon EC2 Windows driver notification

  1. Open the Amazon SNS console at https://console.aws.amazon.com/sns/v3/home.

  2. In the navigation pane, choose Subscriptions.

  3. Select the checkbox for the subscription and then choose Actions, Delete subscriptions. When prompted for confirmation, choose Delete.