DIR_LIBRARY_RMT is a SAP Parameter attribute which is used to control Path to the remote kernel library information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
DIR_LIBRARY_RMT denotes the path to a remote SAP kernel executable
directory, which has to reside on the database server. It has to be
specified in the operating system notation of the respective application
server.
(The remote SAP kernel executable directory contains an .ilelib<(>
<<)>kernellib> file to indicate the name of the remote SAP kernel
library.)
See SAP Parameter Documentation for full SAP documentation for this profile parameter.