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rlogind(8)
NAME
  rlogind - The remote login server

SYNOPSIS
  rlogind [-aln]

FLAGS
  -a	    Requests the addresses for the hostname, verifying that the name
	    and address correspond.  Normal authentication is bypassed if the
	    address verification fails.

  -l	    Prevents authentication based on the user's $HOME/.rhosts file,
	    unless the user is logging in as the superuser.

  -n	    Disables transport-level, keep-alive messages. The messages are
	    enabled by default.

DESCRIPTION
  The rlogind daemon is the server for the rlogin(1) program.  The server
  provides a remote login facility with authentication based on privileged
  port numbers from trusted hosts.

  The rlogind daemon listens for service requests at the port indicated in
  the login service specification; see services(4).  When a service request
  is received, the following protocol is initiated:

   1.  The server checks the client's source port.  If the port is not in the
       range 512 to 1023, the server aborts the connection.

   2.  The server checks the client's source address and requests the
       corresponding hostname (see gethostbyaddr(3), hosts(4) and named(8).
       If the hostname cannot be determined, the dot-notation representation
       of the host address is used.  If the hostname is in the same domain as
       the server (according to the last two components of the domain name),
       or if the -a flag is given, the addresses for the hostname are
       requested, verifying that the name and address correspond.  Normal
       authentication is bypassed if the address verification fails.

  Once the source port and address have been checked, rlogind proceeds with
  the authentication process described in rshd(8).  It then allocates a
  pseudoterminal (see pty(7)), and manipulates file descriptors so that the
  slave half of the pseudoterminal becomes the stdin, stdout, and stderr for
  a login process.  The login process is an instance of the login(1) program
  invoked with the -f option if authentication has succeeded.  If automatic
  authentication fails, the user is prompted to log in as if on a standard
  terminal line.  The -l option prevents any authentication based on the
  user's .rhosts file, unless the user is logging in as the superuser.

  By default, the rlogind daemon starts the login dialog using the login
  string specified in the message field of the /etc/gettydefs file.  If you
  want to use a customized banner, create an /etc/issue.net or /etc/issue
  file. The rlogind daemon reads the file that exists and writes its contents
  to stdout prior to starting the login dialog. If both files exist, only the
  /etc/issue.net file is used.

  The parent of the login process manipulates the master side of the
  pseudoterminal, operating as an intermediary between the login process and
  the client instance of the rlogin program.  In normal operation, the packet
  protocol described in pty(7) is invoked to provide <Ctrl-s>/<Ctrl-q> type
  facilities and propagate interrupt signals to the remote programs.  The
  login process propagates the client terminal's baud rate and terminal type,
  as found in the TERM environment variable.  The screen or window size of
  the terminal is requested from the client, and window size changes from the
  client are propagated to the pseudoterminal.

  Transport-level, keep-alive messages are enabled unless the -n flag is
  present.  The use of keep-alive messages allows sessions to be timed out if
  the client crashes or becomes unreachable.

  Note that the authentication procedure used here assumes the integrity of
  each client machine and the connecting medium.  This is insecure, but is
  useful in an open environment.

DIAGNOSTICS
  All initial diagnostic messages are indicated by a leading byte with a
  value of 1 (one), after which any network connections are closed.  If there
  are no errors before login is invoked, a null byte is returned as an
  indication of success.

  Try again.
	    A fork by the server failed.

FILES
  /usr/sbin/rlogind
	    Specifies the command path

RELATED INFORMATION
  Commands: login(1).

  Daemons: rshd(8).

  Files: issue(4), issue.net.

  Functions: ruserok(3).

Index for Section 8

Alphabetical listing for R

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