On Tue, 4 Mar 2025 at 11:34, Philipp Marek <philipp@xxxxxxxxxxxxx> wrote: > > > Does OpenSSH scp/sftp mode transfer sparse files correctly, i.e. are > > holes skipped and not transferred as chunks of 0 bytes? [1] > > > > We're asking about sparse files in the >= 1PB range, which consists of > > multi-TB holes with around 600-2000GB of valid data. > > Perhaps rsync would be a good fit here, > it supports --sparse. No, if we would use external tools then mounting NFSv4.2 filesystem via https://github.com/kofemann/ms-nfs41-client/blob/master/cygwin/utils/sshnfs/sshnfs.ksh would be the tool of choice. I'm talking about NATIVE sparse file support in scp/sftp via SEEK_DATA/SEEK_HOLE on POSIX (https://pubs.opengroup.org/onlinepubs/9799919799/functions/lseek.html) or Windows FSCTL_QUERY_ALLOCATED_RANGES (https://learn.microsoft.com/en-us/windows/win32/api/winioctl/ni-winioctl-fsctl_query_allocated_ranges). We need that because people have tried to copy sparse file before, and it either RUINED the files (by making them non-sparse, the holes were filled-in with 0 byte data), or copies took forever because the holes in sparse files are very large (e.g. multi TB size). Lionel _______________________________________________ openssh-unix-dev mailing list openssh-unix-dev@xxxxxxxxxxx https://lists.mindrot.org/mailman/listinfo/openssh-unix-dev
