xref: /freebsd/usr.sbin/nfsd/nfsd.8 (revision 282a3889ebf826db9839be296ff1dd903f6d6d6e)
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28.\"	@(#)nfsd.8	8.4 (Berkeley) 3/29/95
29.\" $FreeBSD$
30.\"
31.Dd March 29, 1995
32.Dt NFSD 8
33.Os
34.Sh NAME
35.Nm nfsd
36.Nd remote
37.Tn NFS
38server
39.Sh SYNOPSIS
40.Nm
41.Op Fl ardut
42.Op Fl n Ar num_servers
43.Op Fl h Ar bindip
44.Sh DESCRIPTION
45The
46.Nm
47utility runs on a server machine to service
48.Tn NFS
49requests from client machines.
50At least one
51.Nm
52must be running for a machine to operate as a server.
53.Pp
54Unless otherwise specified, four servers for
55.Tn UDP
56transport are started.
57.Pp
58The following options are available:
59.Bl -tag -width Ds
60.It Fl r
61Register the
62.Tn NFS
63service with
64.Xr rpcbind 8
65without creating any servers.
66This option can be used along with the
67.Fl u
68or
69.Fl t
70options to re-register NFS if the rpcbind server is restarted.
71.It Fl d
72Unregister the
73.Tn NFS
74service with
75.Xr rpcbind 8
76without creating any servers.
77.It Fl n
78Specifies how many servers to create.
79.It Fl h Ar bindip
80Specifies which IP address or hostname to bind to on the local host.
81This option is recommended when a host has multiple interfaces.
82Multiple
83.Fl h
84options may be specified.
85.It Fl a
86Specifies that nfsd should bind to the wildcard IP address.
87This is the default if no
88.Fl h
89options are given.
90It may also be specified in addition to any
91.Fl h
92options given.
93Note that NFS/UDP does not operate properly when
94bound to the wildcard IP address whether you use -a or do not use -h.
95.It Fl t
96Serve
97.Tn TCP NFS
98clients.
99.It Fl u
100Serve
101.Tn UDP NFS
102clients.
103.El
104.Pp
105For example,
106.Dq Li "nfsd -u -t -n 6"
107serves
108.Tn UDP
109and
110.Tn TCP
111transports using six daemons.
112.Pp
113A server should run enough daemons to handle
114the maximum level of concurrency from its clients,
115typically four to six.
116.Pp
117The
118.Nm
119utility listens 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 2 .
135If this fails, or no
136.Tn NFS
137KLD is available,
138.Nm
139will exit with an error.
140.Pp
141If
142.Nm
143is to be run on a host with multiple interfaces or interface aliases, use
144of the
145.Fl h
146option is recommended.
147If you do not use the option NFS may not respond to
148UDP packets from the same IP address they were sent to.
149Use 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.
152The
153.Nm ipfw
154utility
155would then be used to block nfs-related packets that come in on the outside
156interface.
157.Pp
158The
159.Nm
160utility has to be terminated with
161.Dv SIGUSR1
162and cannot be killed with
163.Dv SIGTERM
164or
165.Dv SIGQUIT .
166The
167.Nm
168utility needs to ignore these signals in order to stay alive as long
169as possible during a shutdown, otherwise loopback mounts will
170not be able to unmount.
171If you have to kill
172.Nm
173just do a
174.Dq Li "kill -USR1 <PID of master nfsd>"
175.Sh EXIT STATUS
176.Ex -std
177.Sh SEE ALSO
178.Xr nfsstat 1 ,
179.Xr kldload 2 ,
180.Xr nfssvc 2 ,
181.Xr exports 5 ,
182.Xr ipfw 8 ,
183.Xr mountd 8 ,
184.Xr nfsiod 8 ,
185.Xr rpcbind 8
186.Sh HISTORY
187The
188.Nm
189utility first appeared in
190.Bx 4.4 .
191