NI-Sync 21.3 Bug Fixes


The following items are notable issues fixed between the release of NI-Sync 21.0 and NI-Sync 21.3, including additional patches and service packs. If you have an issue ID, you can search this list to validate that the issue has been fixed. This is not an exhaustive list of issues fixed in the current version of NI-Sync.

Bug Number

Legacy ID




NI-Sync skews system clock to conform to TSN clock

When setting the system time on a NI Linux RT RIO controller with NI-Sync installed, the system clock will skew by a factor of 10/9 until the offset is corrected, instead of immediately snapping back.


Follow the steps listed in this document or uninstall NI-Sync if it is not needed.

Reported Version:

NI-Sync 16.0

Resolved Version:

NI-Sync 21.3



1509459 399570

LabVIEW Slows Down When NI-Sync Terminal Control is Created on Linux RT System

When a user creates an NI-Sync terminal control or constant in a VI in the context of a Linux RT target, LabVIEW becomes slow in responding to edit actions, including dragging and placing nodes on the block diagram.


To prevent the sluggishness in LabVIEW, do the following:
  1. Right-click the control or constant and select I/O Name Filtering from the shortcut menu.
  2. In the Filter Names dialog box, select Allow Undefined Names.

Reported Version:

NI-Sync: 20.1

Resolved Version:

NI-Sync: 21.3


Jul 27, 2021

Additional Patch Information

Installing some patches may require certain additional steps or considerations. Please refer to the following table for more information about patches for this release.

These patches currently do not have any special instructions.

Glossary of Terms


  • Bug ID - When an issue is reported to NI, you may be given this ID or find it on  You may also find IDs posted by NI on the discussion forums or in KnowledgeBase articles.
  • Legacy ID – An older issue ID that refers to the same issue.  You may instead find this issue ID in older known issues documents.
  • Description - A few sentences which describe the problem. The brief description given does not necessarily describe the problem in full detail.
  • Workaround - Possible ways to work around the problem.
  • Reported Version - The earliest version in which the issue was reported.
  • Resolved Version - Version in which the issue was resolved or was no longer applicable. "N/A" indicates that the issue has not been resolved.
  • Date Added - The date the issue was added to the document (not the reported date).