Paramiko SFTP file renaming: OSError('Extended request not supported.')

Question

I can't find anything about this exception. I am trying to rename a remote file on a local (Windows) SFTP server with fsspec. Paramiko behind the scenes is doing a posix_rename(). What does the error mean?

fs.rename(old_file_path, new_file_path)

Paths look like /folder/file.ext.

I can rename files with other FTP clients on that same server.

You might also try with the related sshfs: https://github.com/fsspec/sshfs — mdurant, Jan 10 '22 at 21:51

Martin Prikryl · Answer 1 · 2023-08-22T13:01:15.797

Indeed, fsspec SFTPFileSystem.mv calls Paramiko SFTPClient.posix_rename. That's imo a bad choice. The SFTPClient.posix_rename internally uses a proprietary OpenSSH posix-rename@openssh.com extension, which is naturally not supported by most other SFTP servers (such as yours).

I do not know what is the best solution/workaround. You can probably add your own "file system" implementation based on SFTPFileSystem, reimplementing SFTPFileSystem.mv to call standard Paramiko SFTPClient.rename (which uses standard SFTP rename request).

score 1 · Accepted Answer · answered Jan 11 '22 at 14:10

1

Actually, I just found that the SFTPClient is exposed through the SFTPFileSystem and I can call rename() on it directly, which worked!

fs.ftp.rename("testfile.txt", "x")

answered Jan 11 '22 at 14:10

cdonner

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(feel free to accept your own answer, but also you might propose the PR to fsspec) – mdurant Jan 11 '22 at 20:56
@mdurant I will do that, and thank you for your input! – cdonner Jan 12 '22 at 01:27
https://github.com/fsspec/filesystem_spec/pull/884 – mdurant Jan 12 '22 at 14:21

Paramiko SFTP file renaming: OSError('Extended request not supported.')

2 Answers2