-h, --help            show this help message and exit
--host HOST, -H HOST  Hostname to check.
--port PORT, -p PORT  TCP port to check.
--connect-host CONNECT_HOST, --ip CONNECT_HOST, -I CONNECT_HOST
                      Connect to this host instead of --host.
--connect-port CONNECT_PORT
                      Connect to this port instead of --port.
--starttls {smtp,imap,xmpp,quassel}
                      Send the protocol-specific messages to enable TLS.
--check-pkix          Additionally perform traditional checks on the
                      certificate (ca trust path, hostname, expiry).
--min-days-valid MIN_DAYS_VALID
                      Minimum number of days a certificate has to be valid.
                      Format: INTEGER[,INTEGER]. 1st is #days for warning,
                      2nd is critical.
--no-dnssec           Continue even when DNS replies aren't DNSSEC
                      authenticated.
--nameserver NAMESERVER
                      Use a custom nameserver.
--timeout TIMEOUT     Network timeout in sec. Default: 10
--version             show program's version number and exit