xref: /freebsd/usr.sbin/rpc.statd/rpc.statd.8 (revision c4f6a2a9e1b1879b618c436ab4f56ff75c73a0f5)
1.\" -*- nroff -*-
2.\"
3.\" Copyright (c) 1995 A.R.Gordon, andrew.gordon@net-tel.co.uk
4.\" All rights reserved.
5.\"
6.\" Redistribution and use in source and binary forms, with or without
7.\" modification, are permitted provided that the following conditions
8.\" are met:
9.\" 1. Redistributions of source code must retain the above copyright
10.\"    notice, this list of conditions and the following disclaimer.
11.\" 2. Redistributions in binary form must reproduce the above copyright
12.\"    notice, this list of conditions and the following disclaimer in the
13.\"    documentation and/or other materials provided with the distribution.
14.\" 3. All advertising materials mentioning features or use of this software
15.\"    must display the following acknowledgement:
16.\"	This product includes software developed by the University of
17.\"	California, Berkeley and its contributors.
18.\" 4. Neither the name of the University nor the names of its contributors
19.\"    may be used to endorse or promote products derived from this software
20.\"    without specific prior written permission.
21.\"
22.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32.\" SUCH DAMAGE.
33.\"
34.\" $FreeBSD$
35.\"
36.Dd September 19, 1995
37.Dt RPC.STATD 8
38.Os
39.Sh NAME
40.Nm rpc.statd
41.Nd host status monitoring daemon
42.Sh SYNOPSIS
43.Nm
44.Op Fl d
45.Sh DESCRIPTION
46The
47.Nm
48utility
49is a daemon which co-operates with
50.Nm
51daemons on other hosts to provide
52a status monitoring service.  The daemon accepts requests from
53programs running on the local host (typically,
54.Xr rpc.lockd 8 ,
55the NFS file locking daemon) to monitor the status of specified
56hosts.  If a monitored host crashes and restarts, the remote daemon will
57notify the local daemon, which in turn will notify the local program(s)
58which requested the monitoring service.  Conversely, if this host crashes
59and re-starts, when the
60.Nm
61re-starts, it will notify all of the hosts which were being monitored
62at the time of the crash.
63.Pp
64The following option is available:
65.Bl -tag -width indent
66.It Fl d
67Cause debugging information to be written to syslog, recording
68all RPC transactions to the daemon.  These messages are logged with level
69LOG_DEBUG and facility LOG_DAEMON.  Error conditions are logged irrespective
70of this option, using level LOG_ERR.
71.El
72.Pp
73The
74.Nm
75utility must NOT be invoked by
76.Xr inetd 8
77because the protocol assumes that the daemon will run from system start time.
78Instead, it should be run from
79.Xr rc 8
80after the network has been started.
81.Sh FILES
82.Bl -tag -width /usr/include/rpcsvc/sm_inter.x -compact
83.It Pa /var/db/statd.status
84non-volatile record of currently monitored hosts.
85.It Pa /usr/include/rpcsvc/sm_inter.x
86RPC protocol specification used by local applications to register monitoring requests.
87.El
88.Sh SEE ALSO
89.Xr syslog 3 ,
90.Xr rc 8 ,
91.Xr rpc.lockd 8
92.Sh BUGS
93There is no means for the daemon to tell when a monitored host has
94disappeared permanently (eg. catastrophic hardware failure), as opposed
95to transient failure of the host or an intermediate router.  At present,
96it will re-try notification attempts at frequent intervals for 10 minutes,
97then hourly, and finally gives up after 24 hours.
98.Pp
99The protocol requires that symmetric monitor requests are made to both
100the local and remote daemon in order to establish a monitored relationship.
101This is convenient for the NFS locking protocol, but probably reduces the
102usefulness of the monitoring system for other applications.
103.Pp
104The current implementation uses more than 1Kbyte per monitored host in
105the status file (and also in VM).  This may be inefficient for NFS servers
106with large numbers of clients.
107.Sh STANDARDS
108The implementation is based on the specification in X/Open CAE Specification
109C218, "Protocols for X/Open PC Interworking: XNFS, Issue 4", ISBN 1 872630 66 9
110