If Revolution R Enterprise for Linux is installed in a location other than the default (/usr/lib64/Revo-7.3.0) or an additional open source installation of R exists on the same system, the link /usr/bin/R linking to the Revolution R Enterprise executable may not be created at installation. By default, RStudio Server will use the R installation is finds first in the path, typically /usr/bin/R. If RStudio Server is unable to start a Revolution R session or starts an open source R session instead, check for the presence of /usr/bin/R and ensure it is a link to Revo64:
# ls -la /usr/bin
/R/usr/bin/R -> /usr/lib64/Revo-7.3.0/bin/Revo64
If not, you may create the soft link to the correct location of Revo64 or, if an existing link or R executable exists, you may rename that file and create the correct link.