8. RLOGIN: Logging In to a Remote Host

Introduction

RLOGIN is the Berkeley R Command utility you can use to log in to a remote host. RLOGIN provides a functionality similar to TELNET except that RLOGIN follows more of a UNIX format.

This chapter is a basic use summary of the RLOGIN command.

Before you use RLOGIN, be sure your host or username is registered in the remote system's ~/.rhosts file (if UNIX) or SYS$LOGIN:.RHOSTS file.

See the Management Guide, Chapter 16, Managing R Commands, for information on host equivalence files.

To use Kerberos version 4 authentication with the remote host, make sure that your username and Kerberos realm are in the remote host's ~/.klogin file (if UNIX) or SYS$LOGIN:.KLOGIN file (if OpenVMS).

To use Kerberos V4 authentication, your system manager must configure TCPware's Kerberos Services. You must also first get a ticket-granting ticket (TGT) from the Kerberos Server.

See Chapter 4, Kerberos User Commands, for details on getting a TGT.

With Kerberos V4 authentication, you can specify the Kerberos realm using the /REALM qualifier. If omitted, the TCPWARE_KERBV4_REALM logical value determines the realm.

RLOGIN first tries to use Kerberos V4 authentication if requested, then falls back to using standard authentication if Kerberos authentication fails.

To close an RLOGIN connection, simply log out of the remote system.

If you are designated by the system administrator as having password authentication using Token Authentication, you need to enter the PASSCODE in addition to the username and password at a separate PASSCODE: prompt. Depending on which type of SecurIDW card you were assigned, do one of the following:

  Enter a combination of your personal identification number (PIN) and the tokencode that appears on the card (with no separating space) at the PASSCODE: prompt

  Enter your PIN on the PINPAD] card and the resulting tokencode that appears on the card at the PASSCODE: prompt.

See Chapter 14, Token Authentication: Protecting Logins, for details on obtaining PASSCODEs.


 

RLOGIN

Logs in to a remote host from your local host without entering a remote username and password. The remote host must provide login service (for standard authentication) or the klogin service (for Kerberos version 4 authentication).

You can log in to the remote host with a different username by specifying the /USER qualifier.

When RLOGIN starts up, it processes the flow control characters Ctrl/S and Ctrl/Q locally unless the remote host instructs otherwise. RLOGIN passes all other keystrokes directly to the remote process and perform according to conventions established on the remote host.

The special RLOGIN commands in Table 8-1 are available once you start the connection to the remote host. Enter the special RLOGIN commands as the first character on a line.

Table 8-1     Special RLOGIN Commands

Command

Purpose

~.

Closes the connection and exits RLOGIN.

~^Z

Spawns a subprocess on the local host and connects SYS$INPUT, SYS$OUTPUT, and SYS$ERROR to that process. When the subprocess logs out, control returns to the remote session.

~~

Note!     You cannot spawn with CAPTIVE accounts.

Sends a single tilde to the remote system.

 

Format

RLOGIN host

Parameter

host

Name or internet address of the remote host where you want to log in.

Qualifiers

/AUTHENTICATION[=auth-type]

Determines the authentication method. If KERBV4 (or you omit the value), uses Kerberos v4 authentication. If NULL (or you omit the qualifier), uses standard authentication.

/EIGHTBIT

Accepts eight-bit data from the terminal and sends it to the remote system. The default is that only seven-bit data is sent.

/ESCAPE_CHARACTER=char

New escape character for issuing special RLOGIN commands. The default escape character is the ~ (tilde) character.

To close your session from your local host, use a period (.) as the escape command.

/LOG=file

Logs a copy of the output to the specified file. Output continues to be directed to SYS$OUTPUT while it is being recorded in the log file. The default is no logging.

/LOWERCASE (default)
/NOLOWERCASE

/LOWERCASE sends your local username to the remote host in lowercase (the default).  /NOLOWERCASE preserves any uppercase characters in the local username.

/REALM=realm

Assigns the name of the Kerberos realm. Use if the Kerberos Server resides in a different realm than the local host. Use with the /AUTHENTICATION=KERBV4 qualifier and value. RLOGIN converts realm to lowercase unless you enclose it in quotes.

/TERMINAL_SPEED=baud

Terminal speed in baud rate. The default is the current speed of your terminal.

/TERMINAL_TYPE=type

Resets the current terminal type to the specified type. The allowable types you can use to override the current type are VT100, VT200, VT300, and VT400.

The remote terminal type is the same as the local terminal type. If the terminal's virtual size (rows, columns, or pixels) changes during the RLOGIN session, RLOGIN provides the remote host with the new information.

/TRUNCATE[=n]

Truncates the local OpenVMS username to n number of characters. The n value must be greater than zero or the command aborts with an error. The default is eight characters.

If the local username is also the remote username (if you omit the /USER qualifier), TCPware also truncates the remote username to the indicated length. However, it never truncates a remote username specified explicitly with the /USER qualifier.

/USER=remote-username

Username on the remote host that is different from the username with which you are currently logged in to the local host. TCPware never truncates an explicitly specified remote username (see the /TRUNCATE qualifier). The remote-username is converted to lowercase unless you enclose it in quotes or use the /NOLOWERCASE qualifier.

Examples

1   Each of these equivalent commands opens a connection to host IRIS using standard authentication:

RLOGIN IRIS
RLOGIN /AUTH=NULL IRIS

2   This command opens a connection to remote host IRIS, using Kerberos version 4 authentication. The Kerberos Server resides in the daisy.com realm.

RLOGIN /AUTH=KERBV4 /REALM=DAISY.COM IRIS /USER="Smith"

The quotes around Smith are necessary because the name contains a mix of upper- and lowercase characters that you would want to preserve in sending the command. Without the quotes, RLOGIN converts the name to lowercase, which then may not match the username on the remote host.

3   This command opens a connection to remote host IRIS, using Kerberos version 4 authentication. Because /REALM is omitted, the TCPWARE_KERBV4_REALM logical value determines the Kerberos realm.

RLOGIN/AUTH IRIS