SSH_FX_OP_UNSUPPORTED when creating sftp repository


On windows, I try to create a sftp repository but when I use ;

repository create sftp --path="/" --host="" --username="xxxxx" --sftp-password="xxxxx" --known-hosts="C:\Users\xxxxx\.ssh\known_hosts"

I have this error :slight_smile:

WARN unable to persist sharding parameters: unexpected error renaming file on SFTP: sftp: "Operation not supported." (SSH_FX_OP_UNSUPPORTED)

ssh problem or kopia problem ?



Do you know what software and version is running at the other end?
(sounds like it doesn’t support renames, which is bad I guess)


It’s sftp server by n/software

the free version

Do you know other free sftp server that work with kopia ?

Thanks in advance


Well, I’m from the unix side, there everyone can run “OpenSSH”, which added “posix-rename” in 2007-2008, so that might be why noone else have seen this problem.
As for sftp servers on Windows, I can’t really help. If you have WSL(2?) on a windows box, sshd and sftp should be a part of it.

Seems like there are lots of guides on how to use WSL(2) to allow someone to ssh/scp/sftp into it, here is one:

Don’t know if I am looking at the right part, but there is a setting for how to handle certain types of renames

If enabled and the destination file already exists, the destination file will be renamed to have a temporary extension as a backup. The original file will be renamed to the destination file and the temporary file will be deleted. If the rename operation fails for any reason the temporary file is renamed back to the destination file so effectively no changes occur when the rename fails.

  • 0 - Disabled (default)
  • 1 - Enabled

so if this indeed is the wrong part of their webdocs, do look at the manual for your sftp server and see if there is a setting or knob to twist that has anything to do with renames, and retry again.

I will try it and even the open-ssh windows version :wink:

Thanks for your answer


SFTP Drive is just a client part for sftp

Ok, sorry. googling for “sftp rename” and the company name brought so many wildly different hits. The point still stands, there could be an option in the program to control different outcomes of rename operations. Also, if it is a commercial program, one could be so bold as to ask them for help, since that would presumably be a part of what you pay for.
See if you can run kopia in the most verbose possible manner while getting the error, to see if it will show exactly what command it sent, that would at least help when issuing a ticket to the company that makes the product.