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. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.Dd July 5, 2024 29.Dt MOUNTD 8 30.Os 31.Sh NAME 32.Nm mountd 33.Nd service remote 34.Tn NFS 35mount requests 36.Sh SYNOPSIS 37.Nm 38.Op Fl 2AdelNnRrSs 39.Op Fl h Ar bindip 40.Op Fl p Ar port 41.Op Ar exportsfile ... 42.Sh DESCRIPTION 43The 44.Nm 45utility is the server for 46.Tn NFS 47mount requests from other client machines. 48It listens for service requests at the port indicated in the 49.Tn NFS 50server specification; see 51.%T "Network File System Protocol Specification" , 52RFC1094, Appendix A and 53.%T "NFS: Network File System Version 3 Protocol Specification" , 54RFC1813, Appendix I. 55.Pp 56The following options are available: 57.Bl -tag -width indent 58.It Fl 2 59Allow the administrator to force clients to use only the 60version 2 61.Tn NFS 62protocol to mount file systems from this server. 63.It Fl A 64Silence the warnings related to 65.Dq administrative controls . 66These warnings remind users that an exported 67.Dq administrative control 68directory that is not a local server file system mount point 69actually exports the entire local file system and not just 70the subtree below the directory exported. 71(See 72.Xr exports 5 ) 73.It Fl d 74Output debugging information. 75.Nm 76will not detach from the controlling terminal and will print 77debugging messages to stderr. 78.It Fl e 79Ignored; included for backward compatibility. 80.It Fl h Ar bindip 81Specify specific IP addresses to bind to for TCP and UDP requests. 82This option may be specified multiple times. 83If no 84.Fl h 85option is specified, 86.Nm 87will bind to 88.Dv INADDR_ANY . 89Note that when specifying IP addresses with 90.Fl h , 91.Nm 92will automatically add 93.Li 127.0.0.1 94and if IPv6 is enabled, 95.Li ::1 96to the list. 97.It Fl l 98Cause all succeeded 99.Nm 100requests to be logged. 101.It Fl N 102Cause 103.Nm 104to execute in the foreground instead of in daemon mode. 105.It Fl n 106Allow non-root mount requests to be served. 107This should only be specified if there are clients such as PC's, 108that require it. 109It will automatically clear the vfs.nfsd.nfs_privport sysctl flag, which 110controls if the kernel will accept NFS requests from reserved ports only. 111.It Fl p Ar port 112Force 113.Nm 114to bind to the specified port, for both 115.Dv AF_INET 116and 117.Dv AF_INET6 118address families. 119This is typically done to ensure that the port which 120.Nm 121binds to is a known quantity which can be used in firewall rulesets. 122If 123.Nm 124cannot bind to this port, an appropriate error will be recorded in 125the system log, and the daemon will then exit. 126.It Fl R 127Do not support the Mount protocol and do not register with 128.Xr rpcbind 8 . 129This can be done for NFSv4 only servers, since the Mount protocol is not 130used by NFSv4. 131Useful for NFSv4 only servers that do not wish to run 132.Xr rpcbind 8 . 133.Xr showmount 8 134will not work, however since NFSv4 mounts are not shown by 135.Xr showmount 8 , 136this should not be an issue for an NFSv4 only server. 137.It Fl r 138Allow mount RPCs requests for regular files to be served. 139Although this seems to violate the mount protocol specification, 140some diskless workstations do mount requests for 141their swapfiles and expect them to be regular files. 142Since a regular file cannot be specified in 143.Pa /etc/exports , 144the entire file system in which the swapfiles resides 145will have to be exported with the 146.Fl alldirs 147flag. 148.It Ar exportsfile 149Specify an alternate location 150for the exports file. 151More than one exports file can be specified. 152.It Fl S 153Tell mountd to suspend/resume execution of the nfsd threads whenever 154the exports list is being reloaded. 155This avoids intermittent access 156errors for clients that do NFS RPCs while the exports are being 157reloaded, but introduces a delay in RPC response while the reload 158is in progress. 159If 160.Nm 161crashes while an exports load is in progress, 162.Nm 163must be restarted to get the nfsd threads running again, if this 164option is used. 165.It Fl s 166Cause 167.Nm 168to skip automatic binding to localhost for IPv4 and IPv6. 169This option is meaningless unless 170.Fl h 171has also been used. 172.El 173.Pp 174When 175.Nm 176is started, 177it loads the export host addresses and options into the kernel 178using the 179.Xr nmount 2 180system call. 181After changing the exports file, 182a hangup signal should be sent to the 183.Nm 184daemon 185to get it to reload the export information. 186After sending the SIGHUP 187(kill \-s HUP `cat /var/run/mountd.pid`), 188check the syslog output to see if 189.Nm 190logged any parsing 191errors in the exports file. 192.Pp 193If multiple instances of 194.Nm 195are being run, either in multiple jails or both within 196and outside of a jail, care must be taken to export 197any given file system in only one of the instances. 198Note that the 199.Va allow.nfsd 200jail parameter is required to allow 201.Nm 202to run in a jail. 203See 204.Xr jail 8 205for more information. 206.Pp 207If 208.Nm 209detects that the running kernel does not include 210.Tn NFS 211support, it will attempt to load a loadable kernel module containing 212.Tn NFS 213code, using 214.Xr kldload 2 . 215If this fails, or no 216.Tn NFS 217KLD was available, 218.Nm 219exits with an error. 220When run in a jail, the 221.Xr kldload 2 222must be done outside the jail, typically by adding 223.Dq nfsd 224to 225.Va kld_list 226in the 227.Xr rc.conf 5 228file on the jail host. 229.Sh FILES 230.Bl -tag -width /var/run/mountd.pid -compact 231.It Pa /etc/exports 232the list of exported file systems 233.It Pa /var/run/mountd.pid 234the pid of the currently running mountd 235.It Pa /var/db/mountdtab 236the current list of remote mounted file systems 237.El 238.Sh SEE ALSO 239.Xr nfsstat 1 , 240.Xr kldload 2 , 241.Xr nfsv4 4 , 242.Xr exports 5 , 243.Xr rc.conf 5 , 244.Xr jail 8 , 245.Xr nfsd 8 , 246.Xr rpcbind 8 , 247.Xr showmount 8 248.Sh HISTORY 249The 250.Nm 251utility first appeared in 252.Bx 4.4 . 253