/opt/pixar/RenderManProServer-24.0

/opt/pixar/RenderManForKatana-24.0/plugins/Resources/katana4.0

Default shader search paths for RenderMan match the default paths in the rendermn.ini file. If additional search paths are needed then you will need to set up the RMAN_SHADERPATH and/or RMAN_RIXPLUGINPATH environment variables to include your specific paths.  These environment variables replace rather than append to the default paths, so you will need to include the default paths as well.