Hello, I am running R code on parallelcluster which is slurm based. Upon running job on compute, I receive below error: Error in .External2(C_X11, paste0("png::", filename), g$width, g$height, : unable to start device PNG Calls: ggsave -> dev -> png_dev In addition: Warning message: In png_dev(..., res = dpi, units = "in") : unable to open connection to X11 display '' Execution halted I enabled x11 forwarding on compute and master via changes in sshd_config. x11, xorg and other packages installed as well. The script runs fine on master and compute when logged in to it and triggered manually. But fails when run via batch job script or non-interactively. Please If anyone can help.