Active and passive modes

Buru SFTP Server supports FTP in both active and passive mode, giving users flexibility in how they connect to the server. In the legacy active mode, the client opens a port and listens for the server's connection. In passive mode, the server opens a port, and the client connects to it. This dual-mode support ensures compatibility with various network configurations, including firewalls and NAT setups.

TLS/SSL

FTPS transfers are secured using the latest version of TLS (a protocol that used to be called SSL). For specific scenarios, it is still possible to run plain FTP without a secure transmission channel, but unless you have a really good reason to do so, this is not recommended.

The server supports both Explicit and Implicit modes for FTP.

Implicit mode

The connection starts with encryption enabled from the very beginning, without requiring additional client commands.

Explicit mode

The client establishes an unencrypted connection and can optionally request an upgrade to a secure TLS/SSL connection.

Supported extensions

Buru server supports common FTP extensions including:

• EPRT and EPSV (Extended Passive Mode) for improved performance with clients connecting from behind the firewall and for IPv6;
• CLNT and CSID (Client / Server Identification) for better identification of connecting clients;
• MLST and MLSD for easier machine-processing of listing output;
• and many others.

See also:

• Documentation: FTP/FTPS protocol configuration