-tlsVerifyClient

The -tlsVerifyClient option is used to define whether an FTP client requires a certificate to access a server.

-tlsVerifyClient

NONE | OPTIONAL | REQUIRE

NONE

The FTP server does not request a certificate from the FTP client.
NONE is the default.

OPTIONAL

The FTP server requests the FTP client to send its certificate. If the client refuses to do this or supplies an invalid certificate, access is nevertheless allowed.

REQUIRE

The FTP client must transfer a valid certificate, otherwise access is refused.