Known Issues


64-core Machines

The Zync 64-core machine type is currently in alpha and thus can still be unstable for some workloads. In particular certain Vray scenes seem to cause node failures consistently, though it is currently unknown which if any Vray features are to blame. The Zync Engineering team is currently tracking this issue to determine exact cause. If you have any issues using 64-core machines please write us at

Time limit on preflight phase

For some jobs like Houdini before the actual rendering there is a preflight. In the preflight intermediate files are created. Ex. for Houdini, standalone files (.ifd,.ass) are created from a .hip file. It can take long time, especially when the scene contains simulations. For Renderman and Houdini limit is 2h.

Note: For Houdini one can use file caches generated locally to make the export faster.

Lack of support for Unicode characters

Currently there is no Unicode support in Zync, neither for scenes nor for assets.

Lack of support for special characters in file paths

Valid filenames and paths must contain only lower- and upper-case ASCII characters, spaces, dashes, underscores, and periods.

Lack of support for UNC-style paths

For Windows users, UNC-style paths are not supported on Zync. We recommend using drive-letter-based paths, i.e. mapped network drives.

GOOD: Drive-letter paths:


BAD: UNC-style paths:


Client App

The application "" can't be opened

This can happen when upgrading to the latest version of the Zync Client App. It's caused by a bug in OS X which causes older application data to hang around.

If you get this error message, follow this procedure:

  1. Move the entire /Applications/ZYNC directory to the trash; this uninstalls the Zync Client App.
  2. Restart your computer; this clears the OS X cache which causes this error.
  3. Reinstall the Zync Client App as usual; it should now start normally.

Cannot install Client App RPM

It may happen that the installation of the Client App RPM fails with the following errror:

# rpm -ivh zync-1.26.57-2.noarch.rpm
Transaction check error:
  file / from install of zync-1.26.57-2.noarch conflicts with file from package filesystem-3.2-21.el7.x86_64

In such case, there are two workarounds:

  1. Use the --force flag:

    $ rpm -ivh --force zync-1.26.57-2.noarch.rpm
  2. Extract the .jar file from the .deb client package and run it manually:

    $ ar x zync_1.26.57_all.deb
    $ tar xf data.tar.xz
    $ java -jar usr/local/zync/Zync.jar


Workaround for rendering stills in chunks/regions over large number of machines.

  1. Go to the Outliner by selecting Windows -> Outliner.

  2. In the Outliner select Display and then uncheck DAG objects only.

  3. In the Outliner find the defaultArnoldRenderOptions node and then open the Attribute Editor. To open the Attribute Editor Go to Windows -> General Editors -> Attribute Editor.

  4. In the Attribute Editor scroll down until you see Region Min X, Region Max X, Region Min Y, Region Max y positions

  5. Set the section of the image for the region to cover (Please note that x, y = 0, 0 is located at the top left corner of the screen).

  6. There's two options to take:

    1. Save copies of the same scene, each with different region set.
    2. Create overrides by copying the layers and setting different chunks to be rendered per layer. Setting the overrides is the least troublesome.


Workaround for using Phoenix FD and FumeFX

To use Phoenix FD and FumeFX you will need to use VRay's native VolumeGrid node to load in caches.

  • The VolumeGrid node supports .aur, .f3d, and .vdb type caches.
  • To create a VolumeGrid node go to the V-Ray shelf menu and select V-Ray Volume Grid.

Note: It's important to not use the Phoenix node to link the caches but use this VRayVolumeGrid node instead.


Error when using old Mantra nodes

Before rendering make sure that the Mantra node used for rendering is created with the same version of Houdini that you are using to send the job. If there is mismatch of the versions, your job can error due to incompatible parameters contained by the node.

Spaces in paths

Zync jobs may crash when project filename, output directory path or output filename contains space. In the docs of Houdini ( one can read: "Avoid using spaces in filenames. Although most operating systems support them, many software packages (including Houdini!) sometimes assume that filenames don't have spaces, and this can cause a lot of trouble. Use CamelCase or under_scores instead.".

Colons as path separators in environment variables

Houdini supports both colons and semicolons as dividers between paths in environment variables (e.g. in HOUDINI_OTLSCAN_PATH). Zync supports only semicolons.

Python version on CentOS

Some users of CentOS have an outdated python version. One of the known issues of python 2.7.5 is lack of '_create_default_https_context' function in ssl package. To detect your python version open Windows->Python shell (Alt+Shift+P), the python version should be printed in the first line in the shell. Make sure your version is not older than 2.7.6.

Cinema 4D

Video Textures

Video textures are not supported on C4D on Linux. To use a video texture on Zync it must first be converted to an image sequence.

See an example converting video to an image sequence using ffmpeg.

Please note that, because image sequences typically occupy a larger amount of disk space, this will likely result in a larger amount of data to be uploaded prior to rendering.

Zync uploads the whole Cinema4D content library

When your scene uses textures from the Cinema4D content library, Zync uploads the entire library (studio.lib4d for example) instead of just the needed texture. The general solution is not to use built in libraries and save needed assets somewhere on your filesystem before submiting the scene to Zync. One of the ways to export the assets is to use "Save Project with Assets" mechanism (

preset:// paths fail

Paths beginning with preset:// are not supported on Zync and cause job errors. As with the above issue, the general solution is to save these assets elsewhere on your filesystem before submitting the scene to Zync.