ruptime.1c

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)ruptime.1c	2.2	5/18/87
.TH ruptime 1c
.SH Name
ruptime \- show host status of local machines
.SH Syntax
.B ruptime
[ 
.I options
]
[
.I machinename
] 
.SH Description
.NXR "ruptime command" "description"
The
.PN ruptime
command
gives a status line like 
.MS uptime 1 
for each machine on the local network.
If a 
.I machinename
is given, the status of only the named machine is given.
These status lines are formed from packets broadcast by each host
on the network once a minute.
.PP
Machines for which no
status report has been received for 5 minutes are shown as being down.
.SH Options
.IP \fB\-a\fR 5
.NXR "ruptime command" "options"
Users idle an hour or more are not counted unless this
option is specified.
.IP \fB\-d\fR 5
Display only those hosts that are considered down.
.IP \fB\-l\fR 5
Sort the status list by load average.  If more than one sort
option is given, 
.PN ruptime
uses the last one.
.IP \fB\-r\fR 5
Show only hosts that are up and running.
.IP \fB\-t\fR 5 
Sort the status list by uptime.  If more than one sort option
is given,
.PN ruptime
uses the last one.
.IP \fB\-u\fR 5
Sort the status list by number of users.  If more than one sort
option is given,
.PN ruptime 
uses the last one.
.IP \fB\-\fInn\fR 5
Show only those hosts with
.I nn
or more users.
.SH Restrictions
Because the 
.NXR "ruptime command" "restrictions"
.PN rwhod
daemon sends its information in broadcast packets it generates
a large amount of network traffic.  On large networks the extra
traffic may be objectionable.  Therefore, the 
.PN rwhod
daemon is disabled by default.  To make use of the 
.PN rwhod
daemon for both the local and remote hosts,
remove the comment symbols (#) from in front of the lines specifying
.PN rwhod
in the
.PN /etc/rc
file.
.PP
If the
.PN rwhod
daemon is not running on a remote machine, the machine
may incorrectly appear to be down when you use the 
.PN ruptime
command to determine its status.  See the
.MS rwhod 8
reference page for more information.
.PP
If a system has more than 40 users logged in at once,
the number of users displayed by the 
.PN ruptime
command is incorrect.
Users who login to a machine after that point fail
to increment the user count that appears in the output of the
.PN ruptime
command.
This is due to the maximum size limit of an Ethernet packet,
which is 1500 bytes, and the fact that the 
.PN rwhod
daemon must
broadcast its information in a single packet.
.SH Files
.DT
/usr/spool/rwho/whod.*	Information about other machines
.SH See Also
rwho(1c), rwhod(8c)