xref: /freebsd/usr.sbin/nfsd/nfsd.8 (revision 2a4a1db342263067035ce69a4017c645da63455d)
1.\" Copyright (c) 1989, 1991, 1993
2.\"	The Regents of the University of California.  All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\"    notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\"    notice, this list of conditions and the following disclaimer in the
11.\"    documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\"    must display the following acknowledgement:
14.\"	This product includes software developed by the University of
15.\"	California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\"    may be used to endorse or promote products derived from this software
18.\"    without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\"	@(#)nfsd.8	8.4 (Berkeley) 3/29/95
33.\" $FreeBSD$
34.\"
35.Dd March 29, 1995
36.Dt NFSD 8
37.Os
38.Sh NAME
39.Nm nfsd
40.Nd remote
41.Tn NFS
42server
43.Sh SYNOPSIS
44.Nm
45.Op Fl ardut
46.Op Fl n Ar num_servers
47.Op Fl h Ar bindip
48.Sh DESCRIPTION
49.Nm Nfsd
50runs on a server machine to service
51.Tn NFS
52requests from client machines.
53At least one
54.Nm
55must be running for a machine to operate as a server.
56.Pp
57Unless otherwise specified, four servers for
58.Tn UDP
59transport are started.
60.Pp
61The following options are available:
62.Bl -tag -width Ds
63.It Fl r
64Register the
65.Tn NFS
66service with
67.Xr rpcbind 8
68without creating any servers.
69This option can be used along with the
70.Fl u
71or
72.Fl t
73options to re-register NFS if the rpcbind server is restarted.
74.It Fl d
75Unregister the
76.Tn NFS
77service with
78.Xr rpcbind 8
79without creating any servers.
80.It Fl n
81Specifies how many servers to create.
82.It Fl h Ar bindip
83Specifies which IP address or hostname to bind to on the local host.
84This option is recommended when a host has multiple interfaces.
85Multiple
86.Fl h
87options may be specified.
88.It Fl a
89Specifies that nfsd should bind to the wildcard IP address.
90This is the default if no
91.Fl h
92options are given.  It may also be specified in addition to any
93.Fl h
94options given.  Note that NFS/UDP does not operate properly when
95bound to the wildcard IP address whether you use -a or do not use -h.
96.It Fl t
97Serve
98.Tn TCP NFS
99clients.
100.It Fl u
101Serve
102.Tn UDP NFS
103clients.
104.El
105.Pp
106For example,
107.Dq Li "nfsd -u -t -n 6"
108serves
109.Tn UDP
110and
111.Tn TCP
112transports using six daemons.
113.Pp
114A server should run enough daemons to handle
115the maximum level of concurrency from its clients,
116typically four to six.
117.Pp
118.Nm Nfsd
119listens for service requests at the port indicated in the
120.Tn NFS
121server specification; see
122.%T "Network File System Protocol Specification" ,
123RFC1094 and
124.%T "NFS: Network File System Version 3 Protocol Specification" .
125.Pp
126If
127.Nm
128detects that
129.Tn NFS
130is not loaded in the running kernel, it will attempt
131to load a loadable kernel module containing
132.Tn NFS
133support using
134.Xr kldload 8
135by way of
136.Xr vfsload 3 .
137If this fails, or no
138.Tn NFS
139KLD is available,
140.Nm
141will exit with an error.
142.Pp
143If
144.Nm
145is to be run on a host with multiple interfaces or interface aliases, use
146of the
147.Fl h
148option is recommended.  If you do not use the option NFS may not respond to
149UDP packets from the same IP address they were sent to.  Use of this option
150is also recommended when securing NFS exports on a firewalling machine such
151that the NFS sockets can only be accessed by the inside interface.
152.Nm Ipfw
153would then be used to block nfs-related packets that come in on the outside
154interface.
155.Pp
156.Nm
157has to be terminated with
158.Dv SIGUSR1
159and cannot be killed with
160.Dv SIGTERM
161or
162.Dv SIGQUIT .
163.Nm
164needs to ignore these signals in order to stay alive as long
165as possible during a shutdown, otherwise loopback mounts will
166not be able to unmount.
167If you have to kill
168.Nm
169just do a
170.Dq Li "kill -USR1 <PID of master nfsd>"
171.Sh DIAGNOSTICS
172.Ex -std
173.Sh SEE ALSO
174.Xr nfsstat 1 ,
175.Xr nfssvc 2 ,
176.Xr ipfw 8 ,
177.Xr kldload 8 ,
178.Xr mountd 8 ,
179.Xr nfsiod 8 ,
180.Xr rpcbind 8
181.Sh HISTORY
182The
183.Nm
184utility first appeared in
185.Bx 4.4 .
186