NAME    [Toc]    [Back]

     rwhod - system status server

SYNOPSIS    [Toc]    [Back]

     rwhod [-d]

DESCRIPTION    [Toc]    [Back]

     rwhod is the server which maintains the database used by the
rwho(1) and
     ruptime(1)  programs.   Its  operation  is predicated on the
ability to
     broadcast messages on a network.

     rwhod operates as both a producer and consumer of status information.  As
     a  producer of information it periodically queries the state
of the system
     and constructs status messages which are broadcast on a network.  As a
     consumer of information, it listens for other rwhod servers'
status messages,
 validating them, then recording them in a  collection
of files located
 in the directory /var/rwho.

     The options are as follows:

     -d      Turn on debug mode.

     The server transmits and receives messages at the port indicated in the
     ``who'' service specification; see  services(5).   The  messages sent and
     received, are of the form:

           struct  outmp {
                   char    out_line[8];            /* tty name */
                   char    out_name[8];            /* user id */
                   int32_t out_time;               /* time on */
           };

           struct  whod {
                   char    wd_vers;
                   char    wd_type;
                   char    wd_fill[2];
                   int32_t wd_sendtime;
                   int32_t wd_recvtime;
                   char    wd_hostname[32];
                   int32_t wd_loadav[3];
                   int32_t wd_boottime;
                   struct  whoent {
                           struct  outmp we_utmp;
                           int32_t we_idle;
                   } wd_we[1024 / sizeof (struct whoent)];
           };

     All fields are converted to  network  byte  order  prior  to
transmission.
     The load averages are as calculated by the w(1) program, and
represent
     load averages over the 5, 10, and 15 minute intervals  prior
to a server's
     transmission;  they are multiplied by 100 for representation
in an integer.
  The host name included is that  returned  by  gethostname(3) with any
     trailing  domain  name omitted.  The array at the end of the
message contains
 information about the users logged in to  the  sending
machine.  This
     information  includes  the contents of the utmp(5) entry for
each non-idle
     terminal line and a value indicating  the  time  in  seconds
since a character
 was last received on the terminal line.

     Messages  received  by  the rwho server are discarded unless
they originated
     at an rwho server's port.  In addition, if the host's  name,
as specified
     in  the  message, contains any unprintable ASCII characters,
the message is
     discarded.  Valid messages received by rwhod are  placed  in
files named
     whod.hostname  in the directory /var/rwho.  These files contain only the
     most recent message, in the format described above.

     Status messages are generated  approximately  once  every  3
minutes.

SEE ALSO    [Toc]    [Back]

     ruptime(1), rwho(1)

HISTORY    [Toc]    [Back]

     The rwhod command appeared in 4.2BSD.

BUGS    [Toc]    [Back]

     There  should  be  a way to relay status information between
networks.  Status
 information should be sent only upon request rather than
continuously.
  People often interpret the server dying or network communication
     failures as a machine going down.

OpenBSD     3.6                        December     11,      1993