This section describes the setup and configuration of environments using floating licenses. If you have purchased node-locked licenses, please refer instead to the Node-locked licenses section for information on using your license.


Redshift supports the use of floating licenses which allow licenses to be shared between all machines on your network. The number of floating licenses determines the number of machines which can be rendering with Redshift concurrently.

To use floating licenses, you will need to install the RLM license server software on one computer on your network which has you have designated as your license server. The license server manages your Redshift licenses through a license key. The license key defines the number of computers that can be rendering concurrently and the version(s) of Redshift that can be used.

Note that Redshift is license per-machine, not per-GPU. Once license allows you to render with any number of GPUs on a single machine, including rendering multiple jobs each assigned to a unique subset of GPUs on the machine.

Redshift uses version 12.1BL3 of the RLM license server and supports Windows (32-bit & 64-bit), Linux (64-bit only) and macOS (64-bit Intel only).

  • The RLM license server software is available here (Windows 64-bit)here (Windows 32-bit)here (Linux 64-bit), or here (macOS 64-bit).
  • The bundles include both the generic RLM license server and the specific Redshift license daemon.
  • The Redshift license daemonfiles (redshift.set and redshift.opt) are also available separately here (not platform specific). Note that the Redshift license daemon requires RLM server v12.0 or higher.

Additional information and troubleshooting help for RLM can be found on the RLM support site, including:

MAC Address and License keys

To issue a Redshift license key for floating licenses, you need to provide the Ethernet address (also known as the "MAC Address" or "Host Id") and the host name of the computer you have designated as your license server. The MAC address is a 12 digit hexadecimal number. It can be displayed in a few different ways, for example bcaec524d7c9, BCAEC524D7C9 or BC-AE-C5-24-D7-C9.

There is a MAC address for each network adaptor on your system, including "onboard" Ethernet adaptors (built into the machine's motherboard), Ethernet adapters plugged in to the PCI slots of the machine's motherboard and mobile USB network adaptors (Wi-Fi, Bluetooth, etc..).

Using a mobile network device can often be the best choice as it allows you to easily move your floating licenses to a new license server machine if, for example, your server machine has a hardware failure.

Obtaining your license server's MAC address

To obtain a list of MAC addresses on your Windows machine, open a command prompt and run the command getmac /v or ipconfig /all.

If running getmac /v the MAC address for each network adaptor is listed in the 3rd column. If running ipconfig /all, the MAC address for each network adaptor is shown with the label Physical Address.

On Linux, use the command ifconfig and look for output similar to:

eth0 Link encap:Ethernet HWaddr 00:11:22:33:44:55

The mac address is the string of 6 pairs of 2 hexadecimal digits.

If you are unsure which network adaptor to use, simply run getmac /v (Windows) or ifconfig (Linux) and email a screenshot of the output to and we will select an appropriate one for you.

Obtaining your license server's host name

The command hostname, available on Windows and Linux will print the host name of your machine.

Obtaining your license key

Once you have obtained your MAC address, please send an email to and include the MAC address along with your order number. You will receive a response which includes your license key as an attachment. You can expect a response within 1 hour during our normal business hours of 9AM to 8PM pacific time.

Setting up your license server

System Requirements

The machine you designate as your license server must meet the following requirements:

  • All client workstations and render nodes which will be rendering with Redshift must be able to connect to the license server via TCP/IP.
  • The license server can run on Windows (XP, 7, 8 or 10) 32-bit or 64-bit, Linux 64-bit or macOS 64-bit.
  • The license server must be a physical machine, not a virtual machine.

Installing the RLM license server

Download the Redshift license server bundle here (Windows 64-bit)here (Windows 32-bit)here (Linux 64-bit), or here (macOS 64-bit). Extract the files from the bundle and move them to a folder on your license server machine. The location of the folder is not important.

Installing your license key

Place the license key file you receive from Redshift support to the same folder that contains the extracted RLM server bundle files on your license server. This is the folder that contains the rlm executable (rlm.exe).

Starting the RLM license server

The license server can be run from the command-line, or can be set up to run as a windows service so that it automatically starts when you boot your server. Running from the command-line is convenient for testing, but we recommend running the RLM server as a service once it's been confirmed to be working.

Running the RLM license server from the command line

From the command-line, change directory to the folder which contains the Redshift RLM server files.

pushd C:\redshift_rlm

Run the license server executable, specifying the log folder.

rlm -dlog rlm.log

Running the RLM license server as a Windows service

Installing a service usually requires administrative privileges. Open a command-prompt as Administrator. From the command-line, change directory to the folder which contains the Redshift RLM server files.

pushd C:\redshift_rlm

Then run the following command to tell the rlm server to install itself as a service.

rlm -install_service -service_name RLM-Redshift -dlog +rlm.log

You must then start the RLM-Redshift service (only required the first time).

net start RLM-Redshift

Customizing the license server port

The RLM license server uses port 5053 by default. You can change the default port by editing your license file, then restarting the RLM server.

The example license file below has modified the RLM server port to 5055.

HOST localhost 0BABE00BABE0 5055
ISV redshift
LICENSE redshift redshift-core 2014.01 permanent 1 share=h
  min_timeout=120 start=1-jan-2014 customer=00001 issued=1-jan-2014 
  replace _ck=acdabe28ba ig="c2N25465jtQi~5Ar=9X01G7Y3WDnqCIc0ihvHoGFc

Serving Redshift licenses from an existing license server

If you are already running an RLM license server on your network for another software package, you may be able to configure it to serve your Redshift licenses. Redshift will not work with RLM server versions before v10.0BL2.

If your existing server meets these requirements, simply copy redshift.set and redshift.opt (available here and also including in the RLM license server bundles) along with your license key to the same folder that contains the existing rlm.exe, then restart the RLM server.

Setting up your client machines

Workstations and render nodes are referred to as clients for the purposes of licensing. You must configure each client machine so that it can find the license server and checkout licenses.

Option 1 - Environment Variables

You can configure your client machines to find the license server by defining an environment variable redshift_LICENSE (note that the lowercase 'redshift' is important). This environment variable will specify the hostname or ip address of the license server as well as the port number using the syntax port@hostname or port@ip-address. The default port for the RLM server is 5053, but can be customized if necessary (for example to prevent conflicts with other RLM license servers running on the same machine). See Customizing the license server port above for more details.

For information on how to set up environment variables on macOS, please see this thread:

The method that works best for most Redshift users is the "envpane" one.

Option 2 - Client License File

An alternative to the environment variable method above is to use a client license file.  The license file is a simple text file named redshift.lic containing a single line of the form:

HOST <hostname> ANY <port>

where <hostname> is the hostname or ip address of the license server and <port> is the RLM license server port.

For example, if your license server hostname is myrlmserver and you are using the default port 5053, your client license file would look like:

HOST myrlmserver ANY 5053

The license file should be placed in the License Path on each client machine.  By default this is C:\ProgramData\Redshift\ on Windows and ~/redshift/ on Linux and macOS.

The RLM Web Server

The RLM server provides a web based interface for license server administration.. The web server is started automatically when rlm.exe is running. By default, the web server listens on port 5054. To use the web interface, simply point your web browser to *http://localhost:5054* on the license server.