root@sclrdev:/home/sclr/certs/FreshCerts# curl --ftp-ssl --verbose ftp://{abc}/ -u trup:trup --cacert /etc/ssl/certs/ca-certificates.crt * About to connect() to {abc} port 21 (#0) * Trying {abc}... * Connected to {abc} ({abc}) port 21 (#0) < 220-Cerberus FTP Server - Home Edition < 220-This is the UNLICENSED Home Edition and may be used for home, personal use only < 220-Welcome to Cerberus FTP Server < 220 Created by Cerberus, LLC > AUTH SSL < 234 Authentication method accepted * successfully set certificate verify locations: * CAfile: /etc/ssl/certs/ca-certificates.crt CApath: /etc/ssl/certs * SSLv3, TLS handshake, Client hello (1): * SSLv3, TLS handshake, Server hello (2): * SSLv3, TLS handshake, CERT (11): * SSLv3, TLS alert, Server hello (2): * SSL certificate problem: unable to get local issuer certificate * Closing connection 0 curl: (60) SSL certificate problem: unable to get local issuer certificate More details here: http://curl.haxx.se/docs/sslcerts.html curl performs SSL certificate verification by default, using a "bundle" of Certificate Authority (CA) public keys (CA certs). If the default bundle file isn't adequate, you can specify an alternate file using the --cacert option. If this HTTPS server uses a certificate signed by a CA represented in the bundle, the certificate verification probably failed due to a problem with the certificate (it might be expired, or the name might not match the domain name in the URL). If you'd like to turn off curl's verification of the certificate, use the -k (or --insecure) option.