Sockshost, socksport, socksusername, sockspassword Channel Options

SOCKS connections channel options:  (host),    (port),    (string)    (string)
The,  ,  ,   channel options (for SMTP client channels) are used  to configure SOCKS connections. SOCKS connections (see RFC 1928 and RFC 1929) can be used to traverse a firewall that would not normally permit outbound SMTP message traffic. If the firewall offers a SOCKS service, then one can connect to the firewall&#x27;s SOCKS server ( and  ) and authenticate  (  and  ),  pass over the remote host name and remote port to which one wishes to make an SMTP connection, and then the SOCKS server on the firewall will make the remote connection and transform the SOCKS connection into the desired SMTP connection. The  option specifies the host name of the SOCKS server system. The  option specifies the SOCKS port on the SOCKS server system; by convention, port 1080 is usually used as the SOCKS port. The MTA&#x27;s SOCKS implementation currently only supports the username/password method of SOCKS authentication; the username and password to be used are controlled by the   and   channel options, respectively.

The,  , and    options have no default; the default for the   option is 1080.

In order for these  channel options to take effect, the  outbound TCP/IP channel must also be marked with the    channel option.

See also:
 * nosocks Option
 * socksnoauth Option
 * socksuserpassword Option
 * TCPIP connections and DNS lookups channel options