TELNET Command

Purpose

Use the TELNET command to log on to a foreign host that supports TCP/IP.

Options

Operands

foreign_host

Specifies the name or Internet address of the foreign host. The Internet address can be an IPv4 or IPv6 address.

If you do not specify the name or Internet address of the foreign host, you are prompted for the foreign_host.

Note: Attempting to specify an IPv6 link local address will produce unpredictable results.

port_number

Specifies the port number to which you want to connect on the foreign host. When connecting to a non-Telnet port, the data exchange must follow the protocol recognized by the other port. The default is well-known port 23.

Linemode

Indicates the logon operation. LINEMODE uses the line mode and prevents operation in the transparent (TN3270) mode.

In line mode, the foreign host's output is displayed on your screen one line at a time, without full-screen capabilities. In transparent (TN3270) mode, the foreign host's full-screen capabilities are functional on your local terminal.

Firewall

Specifies that a connection is to be made to a host in transparent (TN3270) mode through a proxy server. TELNET establishes a line-mode connection to the designated foreign host (the proxy server). You conduct a conversation with the proxy server to cause it to establish a connection to the actual destination host. TELNET negotiates the termnial type with that host and will enter 3270 mode if permitted.

TRanslate filename

Specifies a nonstandard translation table file. If this parameter is not specified, TELNET searches sequentially for TELNET TCPXLBIN and STANDARD TCPXLBIN. If neither is found, TELNET uses the compiled translation table. TELNET TCPXLBIN is supplied. The file type is always TCPXLBIN.

A nonstandard translation table is used in line mode only.

Record

Creates a log of interactions with linemode hosts in FILE LOGFILE A. A different file can be selected by issuing a CMS FILEDEF for ddname LOGFILE.

SECURE

A secure Telnet connection will be attempted if the Telnet server supports secure connections. If the Telnet server does not support secure connections or if an SSL server is not running on the local system, the TELNET command will fail. Specifying the SECURE option overrides a SECURETELNETCLIENT NO statement specified on the TCPIP DATA file.

HVCONTinue

Verifies that the host name, domain name, or IP address in the server certificate matches what was specified on the TELNET command. If they do not match, the handshake is allowed to continue. Specifying the HVCONTinue option overrides a HOSTVERIFICATION statement specified in the TCPIP DATA file.

This option is the default.

HVNONE

Specifies that no host verification will be performed. Specifying the HVNONE option overrides a HOSTVERIFICATION statement specified in the TCPIP DATA file.

HVREQuired

Verifies that the host name, domain name, or IP address in the server certificate matches what was specified on the TELNET command. If they do not match, the handshake will fail. Specifying the HVREQuired option overrides a HOSTVERIFICATION statement specified in the TCPIP DATA file.

NOSECURE

A clear Telnet connection will be attempted. If the Telnet server does not support clear connections, the TELNET command fails. This is the default taken when neither SECURE nor NOSECURE is specified, unless overridden by SECURETELNETCLIENT YES in the TCPIP DATA file. Specifying the NOSECURE option overrides the SECURETELNETCLIENT YES statement specified in the TCPIP DATA file.

ADDRTYPE IPV4

ADDRTYPE IPV6

Specifies which type of internet address Telnet will attempt to resolve a host name to. If ADDRTYPE is not specified, Telnet will default to IPv4 for secure connections. For connections which are not secure, Telnet will use the first address returned by the resolver whether it is IPv4 or IPv6.

Usage Notes