FTP compatibility issue with FileZilla Server

I’m trying to set up FTP external storage access. The server is FileZilla. It seems Nextcloud is sending some commands that FileZilla doesn’t like. I’m not sure what to do about it. Here is what the conversation looks like.

> USER username
< 331 Password required for username
> PASS ********
< 230 Logged on
> CWD /
< 250 CWD successful. "/" is current directory.
> TYPE I
< 200 Type set to I
> SIZE /
< 550 File not found
> MDTM /
< 550 File not found

Then it disconnects. I logged in with the Windows FTP client and was able to reproduce the results. Based on my troubleshooting, it appears that FileZilla does not support SIZE or MDTM commands against the root folder or any alias folders. It does support MDTM against actual folders but not SIZE.

If I set the remote folder down a couple levels to a real (non-alias) folder, it fails on the SIZE command, succeeds on MDTM, and then it produces a directory listing and seems to work. However, this is not what I need. All subfolders directly under the FTP root are aliases.

It appears that Nextcloud is logged in just fine, but it never even asks for a directory listing. It has errors on SIZE and MDTM and then disconnects. The only other idea I have, which I may try later, is to replace the aliases in the FTP root with symlinks and see if that works. But, this would not fix it for the root folder. I would have to nest it or something.

Is there anything I can do about this? Ideally it would be nice if Nextcloud would just not try to SIZE or MDTM the folders because otherwise it all works.

Its not nextcloud who managed ftp.
Its the serveur os.

No, that’s not correct. Nextcloud chooses what commands to send the FTP server. And the server OS is also not managing FTP since it’s a 3rd party program.

In any case, I tried it just out of curiosity, and it appears that it does indeed work with the remote subfolder set to a directory symlink instead of a FileZilla folder alias. It still fails on the SIZE command but then succeeds on the MDTM command and comes back with a file listing, and it seems to work fine from there.

sorrrrry, i did not focus on the “EXTERNAL STORAGE” …

This was develop back to nc12 !!!
I don’t know if it is still accurate concerning modern ftp command.

personnaly, i use filezilla, proftpd on my server, and SFTP over ssh

better safe than sorry