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HT Microcode Update PX61/en


Information about the bug

Based on current information, the problem is triggered by specific micro-architectural command sequences on Intel's 6th or 7th generation CPUs with Hyper-Threading enabled. It can, in rare cases, cause unpredictable behavior and, in more rare cases, data loss.

For further information on this topic, please check the following resources:

Update via Distribution

You can fix the problem by installing the latest Intel microcode update. For several Linux distributions, you can find the necessary microcode update in the repositories of your distribution. For Skylake CPUs (Xeon v5) the bug was fixed in version 20170511 and for Kaby-Lake CPUs (Xeon v6) it was fixed in version 20170707.



There are updates for the current Debian stable ("stretch") and oldstable ("jessie") version.


The necessary packages are available for 16.04 LTS and 17.04 via the "-updates" repositories:

You may find additional information about this topic in the following bug report:


The packages which contain the necessary update are available for OpenSUSE 42.2 and 42.3:

Other Operating System

If you are using any other operating system (e.g. Windows), or if there is no update for your Linux distribution yet, you can install the microcode update by updating your BIOS.

Update by updating the BIOS

Performing the BIOS update

A BIOS update can be performed by using our Rescue-System. To initiate the BIOS update, you need to execute the following command:


After initiating the BIOS update with the previously mentioned script, you need to reboot your server.

If your server is not reachable again after 10 minutes, please do not perform a reset, but instead open a support request in your Hetzner Robot.

BIOS version information

The following BIOS versions already include the necessary microcode update:

V5.0.0.11 R1.21.0.SR.2 for D3417-B1x 07/14/2017
V5.0.0.12 R1.8.0.SR.1 for D3417-B2x 05/16/2017

If one of these versions is already installed on your mainboard, then you do not need to perform a BIOS update. You can check which BIOS version you currently have with the following command in our Rescue-System:


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