FTP

TLS session resumption for FTP

FolderSync only support this for EdtFTPj/Pro engine. If using Bitvise FTP server there may be incompatibility, it is then recommended to use SFTP instead.

Issue connection to FileZilla FTP server

It would seem the default self-signed certificate for FTPS Explict connection in FileZilla is not compatible with FolderSync. You can create a compatible X.509 certificate using OpenSSL with this command:

openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -sha256

Issue with vsftpd: 426 Failure reading network stream

After upgrading vsftpd to version 3.0.5-48.3.1, many FTP clients increasingly report the following error, typically at the end of a file upload from a client.

426 Failure reading network stream.

Possible resolution is to set this parameter in /etc/vsftpd.conf: strict_ssl_read_eof=NO