+.It Fl H
+Hash all hostnames and addresses in the output.
+Hashed names may be used normally by
+.Nm ssh
+and
+.Nm sshd ,
+but they do not reveal identifying information should the file's contents
+be disclosed.
+.It Fl p Ar port
+Port to connect to on the remote host.
+.It Fl T Ar timeout
+Set the timeout for connection attempts.
+If
+.Pa timeout
+seconds have elapsed since a connection was initiated to a host or since the
+last time anything was read from that host, then the connection is
+closed and the host in question considered unavailable.
+Default is 5 seconds.
+.It Fl t Ar type
+Specifies the type of the key to fetch from the scanned hosts.
+The possible values are
+.Dq rsa1
+for protocol version 1 and
+.Dq rsa
+or
+.Dq dsa
+for protocol version 2.
+Multiple values may be specified by separating them with commas.
+The default is
+.Dq rsa1 .
+.It Fl v
+Verbose mode.
+Causes
+.Nm
+to print debugging messages about its progress.