SFTP recreated from NULL

We have maintained a special SFTP server for clients to access their own lookup.files table through their choice of SFTP client.

Until recently, that server was implemented with Python and the Paramiko library. It had a significant limitation, in that the SFTP encryption handshake was always done in the main thread, one client connection at a time, and that handshake could be slow, taking a few seconds.

That server has been rebuilt, with a whole different architecture. This server uses the stock Ubuntu sshd daemon with a virtual file system behind it, converting lookup.files records into files for sshd.

This seemed like a good opportunity to move the client sshd daemon to the standard ssh port, 22, so it is there now. Update your client settings, if you are using this.

Let me know if you have any difficulties using this new server setup. I am always ready to fix problems that may be discovered.


This general upgrade also added some security related features, monitoring authentication failures, both ssh and web-server, and blocking ip addresses at too many authentication failures. This runs on a hour-by-hour count, so if you are so unfortunate as to be banned by this system, wait an hour and try again.

If you get banned, and you believe the quota that stopped you was too stingy, please email me with specifics. The limits are generous, so I doubt there will be issues.

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