Arnold uses a floating-license mechanism based on RLM from Reprise Software Inc.

Download RLM Server tools

Licensed users need to install the RLM license manager package which can be downloaded from the following links, make sure to download the right platform for your license server:

Starting the license server

The license server must run on a machine that all the render nodes can connect to. On the server machine, and once you have received a license file from us, you can start the license server with the following command:

rlm -c <license_file>

Note that on some Unix-like systems (Linux, OS X), you may have to type:

./rlm -c <license_file>

if the current directory is not in the system path.

License file

A license file is an ASCII text file with the following structure:

HOST localhost 0036181a1ca6 5053
ISV solidangle
LICENSE solidangle arnold 302 31-dec-2010 1 issued=27-apr-2010
 _ck=14d6cd3634 sig="12N250DgmjQbGgzFcua8gx=C1b8bD1Lt0ihs9d2LT5ER1az

In the above example, the license server is localhost and the port is 5053 (the default port for RLM). If you need to change the license port, you can simply update it in the license file.

Client configuration

On the client machines, Arnold will try to use the localhost as the license server. If your license server is in a different machine, you will need to set the ARNOLD_LICENSE_HOST environment variable and point it to the license server name. It will also try the default RLM port (5053). If you have changed the port in the license file, you must also set the ARNOLD_LICENSE_PORT environment variable so that it matches the port in the license file.

Environment variableDefaultDescription
ARNOLD_LICENSE_HOSTlocalhostLicense server name

It's not possible to specify multiple servers in these variables only, see below.

Multiple license servers

Since Arnold, we also support multiple license servers with additional environment variables. We now also recognize the RLM-standard variables RLM_LICENSE and solidangle_LICENSE.

Licenses will be searched for in the following order:


First, from the contents of solidangle_LICENSE, which can contain a list of multiple servers/ports in the following format:


where server<N> can be port@host or host@port (the port is optional and defaults to 5053).


Second, from the contents of RLM_LICENSE, with the same format as above.


Finally, from the contents of ARNOLD_LICENSE_HOST and ARNOLD_LICENSE_PORT, which together define a single license server target, see above.