i have noticed that while rsyncing (-av) a whole directory (from linux ext4) onto a fat32 filesystem on a usb disk there was a large >4GB file among the files to be copied. while rsync should fail immediately encountering such a job what really happened was strange: rsync continued to read all the other files in the job but nothing has been written to the usb disk anymore. i have noticed this since the i/o on my internal disk went to the max of 120 MB/s and the i/o on the usb disk stayed at 0. at that point i pressed ctrl-c and, remarkably late, got the corresponding error:
rsync error: received SIGINT, SIGTERM, or SIGHUP (code 20) at rsync.c(632) [sender=3.1.0]
rsync: write failed on "/media/luser/usbdisk/folder/dvd.iso": File too large (27)
rsync error: error in file IO (code 11) at receiver.c(389) [receiver=3.1.0]
how to reproduce: format a usb disk with mkfs.vfat and try to rsync a directory containing some files plus a large file over the >2GB fat32 limit.
If the Topic should mean ">4GB":
I can confirm the problem.
The problem is that rsync doesn't know that the destination filesystem is not going to allow a large file until the file grows to be too large. You could probably get an earlier error if you use --preallocate, though.