161 lines
5.1 KiB
Groff
161 lines
5.1 KiB
Groff
.\" Copyright (c) 1983, 1991, 1993
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" from: @(#)rwhod.8 8.2 (Berkeley) 12/11/93
|
|
.\" $NetBSD: rwhod.8,v 1.20 2005/09/12 18:33:56 wiz Exp $
|
|
.\"
|
|
.Dd September 12, 2005
|
|
.Dt RWHOD 8
|
|
.Os
|
|
.Sh NAME
|
|
.Nm rwhod
|
|
.Nd system status server
|
|
.Sh SYNOPSIS
|
|
.Nm
|
|
.Op Fl i Ar interval
|
|
.Op Fl u Ar user
|
|
.Sh DESCRIPTION
|
|
.Nm
|
|
is the server which maintains the database used by the
|
|
.Xr rwho 1
|
|
and
|
|
.Xr ruptime 1
|
|
programs.
|
|
Its operation is predicated on the ability to
|
|
.Em broadcast
|
|
messages on a network.
|
|
.Pp
|
|
The following options are available:
|
|
.Bl -tag -width XXXXXXXXXXX
|
|
.It Fl i Ar interval
|
|
Allows for the broadcast interval to be changed from the default 3 minutes.
|
|
The
|
|
.Ar interval
|
|
argument is the number of seconds to change the interval to, or if the
|
|
value is suffixed by
|
|
.Dq m
|
|
then it is interpreted as minutes.
|
|
The maximum allowed value for the broadcast interval is 11 minutes
|
|
because higher values will cause
|
|
.Xr ruptime 1
|
|
to mark the host as being down.
|
|
.It Fl u Ar user
|
|
Drop privileges and become the user
|
|
.Ar user .
|
|
.El
|
|
.Pp
|
|
.Nm
|
|
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
|
|
.Nm
|
|
servers' status messages, validating them, then recording
|
|
them in a collection of files located in the directory
|
|
.Pa /var/rwho .
|
|
.Pp
|
|
The server transmits and receives messages at the port indicated
|
|
in the
|
|
.Dq who
|
|
service specification; see
|
|
.Xr services 5 .
|
|
The messages sent and received, are of the form:
|
|
.Bd -literal -offset indent
|
|
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)];
|
|
};
|
|
.Ed
|
|
.Pp
|
|
All fields are converted to network byte order prior to
|
|
transmission.
|
|
The load averages are as calculated by the
|
|
.Xr 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 the
|
|
.Xr gethostname 3
|
|
function call, 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
|
|
.Xr 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.
|
|
.Pp
|
|
Messages received by the
|
|
.Xr rwho 1
|
|
server are discarded unless they originated at an
|
|
.Xr rwho 1
|
|
server's port.
|
|
In addition, if the host's name, as specified
|
|
in the message, contains any unprintable
|
|
.Tn ASCII
|
|
characters, the message is discarded.
|
|
Valid messages received by
|
|
.Nm
|
|
are placed in files named
|
|
.Pa whod.hostname
|
|
in the directory
|
|
.Pa /var/rwho .
|
|
These files contain only the most recent message, in the
|
|
format described above.
|
|
.Pp
|
|
Status messages are generated by default approximately once every
|
|
3 minutes.
|
|
.Sh SEE ALSO
|
|
.Xr ruptime 1 ,
|
|
.Xr rwho 1
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
command appeared in
|
|
.Bx 4.2 .
|
|
.Sh BUGS
|
|
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.
|