Hello, We are in the midst of changing our SOP for R on our local cluster. Network access is only available from the head node but we don't want users downloading and compiling packages on the head node. Previously, we asked that all package installations & updates be done by the admins on request but this is unsustainable. We've decided to internally mirror both CRAN and Bioconductor and keep a core of the most used packages on R_HOME/library and update those weekly. Users can also download/install/update other packages from CRAN/Bioconductor using their own local library. What we are trying to work out now are the system settings needed so that install.packages (and eventually biocLite) automatically point to only our internal mirrors without having specify them in the repos argument. After muc h googling, I think I've figured out that we need to set up a ~R/etc/Rprofile.site file to change the default CRAN repository to our local site using options(repos = c(CRAN = "file:////home! /mirrors/no_backup/cran"). Is this all that is needed or do we also need to modify ~R/etc/repositories, changing the URL locations to our local ones and commenting out the other repositories? Anything else we need to do to get install.packages("ape") to work seamlessly for the end user? We want to make it so that only users who really know what they are doing can get around installing from the local mirrors, even if they are accidentally running on the head node. Thanks for any help or suggestions, Jenny Jenny Drnevich, Ph.D. Functional Genomics Bioinformatics Specialist High Performance Biological Computing Program and The Roy J. Carver Biotechnology Center University of Illinois, Urbana-Champaign NOTE NEW OFFICE LOCATION 2112 IGB 1206 W. Gregory Dr. Urbana, IL 61801 USA ph: 217-300-6543 fax: 217-265-5066 e-mail: drnevich@illinois.edu<mailto:drnevich@illinois.edu> [[alternative HTML version deleted]]