xref: /freebsd/sbin/mount_nfs/mount_nfs.8 (revision c92e3fa53306bcaf479bfac3feafc463eb220ce8)
14a4c5285SPeter Wemm.\" Copyright (c) 1992, 1993, 1994, 1995
28fae3551SRodney W. Grimes.\"	The Regents of the University of California.  All rights reserved.
38fae3551SRodney W. Grimes.\"
48fae3551SRodney W. Grimes.\" Redistribution and use in source and binary forms, with or without
58fae3551SRodney W. Grimes.\" modification, are permitted provided that the following conditions
68fae3551SRodney W. Grimes.\" are met:
78fae3551SRodney W. Grimes.\" 1. Redistributions of source code must retain the above copyright
88fae3551SRodney W. Grimes.\"    notice, this list of conditions and the following disclaimer.
98fae3551SRodney W. Grimes.\" 2. Redistributions in binary form must reproduce the above copyright
108fae3551SRodney W. Grimes.\"    notice, this list of conditions and the following disclaimer in the
118fae3551SRodney W. Grimes.\"    documentation and/or other materials provided with the distribution.
128fae3551SRodney W. Grimes.\" 3. All advertising materials mentioning features or use of this software
138fae3551SRodney W. Grimes.\"    must display the following acknowledgement:
148fae3551SRodney W. Grimes.\"	This product includes software developed by the University of
158fae3551SRodney W. Grimes.\"	California, Berkeley and its contributors.
168fae3551SRodney W. Grimes.\" 4. Neither the name of the University nor the names of its contributors
178fae3551SRodney W. Grimes.\"    may be used to endorse or promote products derived from this software
188fae3551SRodney W. Grimes.\"    without specific prior written permission.
198fae3551SRodney W. Grimes.\"
208fae3551SRodney W. Grimes.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
218fae3551SRodney W. Grimes.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
228fae3551SRodney W. Grimes.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
238fae3551SRodney W. Grimes.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
248fae3551SRodney W. Grimes.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
258fae3551SRodney W. Grimes.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
268fae3551SRodney W. Grimes.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
278fae3551SRodney W. Grimes.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
288fae3551SRodney W. Grimes.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
298fae3551SRodney W. Grimes.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
308fae3551SRodney W. Grimes.\" SUCH DAMAGE.
318fae3551SRodney W. Grimes.\"
324a4c5285SPeter Wemm.\"	@(#)mount_nfs.8	8.3 (Berkeley) 3/29/95
338fae3551SRodney W. Grimes.\"
34c92e3fa5SPeter Wemm.\" $Id: mount_nfs.8,v 1.11 1998/05/01 13:52:17 peter Exp $
35f9dc1926SJoerg Wunsch.\""
364a4c5285SPeter Wemm.Dd March 29, 1995
378fae3551SRodney W. Grimes.Dt MOUNT_NFS 8
388fae3551SRodney W. Grimes.Os BSD 4.4
398fae3551SRodney W. Grimes.Sh NAME
408fae3551SRodney W. Grimes.Nm mount_nfs
418fae3551SRodney W. Grimes.Nd mount nfs file systems
428fae3551SRodney W. Grimes.Sh SYNOPSIS
438fae3551SRodney W. Grimes.Nm mount_nfs
44cc75b131SJoerg Wunsch.Op Fl 23KNPTUbcdilqs
458fae3551SRodney W. Grimes.Op Fl D Ar deadthresh
46a62dc406SDoug Rabson.Op Fl I Ar readdirsize
478fae3551SRodney W. Grimes.Op Fl L Ar leaseterm
488fae3551SRodney W. Grimes.Op Fl R Ar retrycnt
498fae3551SRodney W. Grimes.Op Fl a Ar maxreadahead
508fae3551SRodney W. Grimes.Op Fl g Ar maxgroups
518fae3551SRodney W. Grimes.Op Fl m Ar realm
528fae3551SRodney W. Grimes.Op Fl o Ar options
538fae3551SRodney W. Grimes.Op Fl r Ar readsize
548fae3551SRodney W. Grimes.Op Fl t Ar timeout
558fae3551SRodney W. Grimes.Op Fl w Ar writesize
568fae3551SRodney W. Grimes.Op Fl x Ar retrans
578fae3551SRodney W. Grimes.Ar rhost:path node
588fae3551SRodney W. Grimes.Sh DESCRIPTION
598fae3551SRodney W. GrimesThe
608fae3551SRodney W. Grimes.Nm mount_nfs
618fae3551SRodney W. Grimescommand
628fae3551SRodney W. Grimescalls the
638fae3551SRodney W. Grimes.Xr mount 2
648fae3551SRodney W. Grimessystem call to prepare and graft a remote nfs file system (rhost:path)
658fae3551SRodney W. Grimeson to the file system tree at the point
668fae3551SRodney W. Grimes.Ar node.
678fae3551SRodney W. GrimesThis command is normally executed by
688fae3551SRodney W. Grimes.Xr mount 8 .
69a62dc406SDoug RabsonIt implements the mount protocol as described in RFC 1094, Appendix A and
70a62dc406SDoug Rabson.%T "NFS: Network File System Version 3 Protocol Specification" ,
71a62dc406SDoug RabsonAppendix I.
728fae3551SRodney W. Grimes.Pp
738fae3551SRodney W. GrimesThe options are:
748fae3551SRodney W. Grimes.Bl -tag -width indent
752cd1c32cSDoug Rabson.It Fl 2
762cd1c32cSDoug RabsonUse the NFS Version 2 protocol (the default is to try version 3 first
77e2b2b076SPeter Wemmthen version 2).  Note that NFS version 2 has a file size limit of 2
78e2b2b076SPeter Wemmgigabytes.
79a62dc406SDoug Rabson.It Fl 3
802cd1c32cSDoug RabsonUse the NFS Version 3 protocol.
818fae3551SRodney W. Grimes.It Fl D
828fae3551SRodney W. GrimesUsed with NQNFS to set the
838fae3551SRodney W. Grimes.Dq "dead server threshold"
848fae3551SRodney W. Grimesto the specified number of round trip timeout intervals.
858fae3551SRodney W. GrimesAfter a
868fae3551SRodney W. Grimes.Dq "dead server threshold"
878fae3551SRodney W. Grimesof retransmit timeouts,
888fae3551SRodney W. Grimescached data for the unresponsive server is assumed to still be valid.
898fae3551SRodney W. GrimesValues may be set in the range of 1 - 9, with 9 referring to an
908fae3551SRodney W. Grimes.Dq "infinite dead threshold"
918fae3551SRodney W. Grimes(i.e. never assume cached data still valid).
928fae3551SRodney W. GrimesThis option is not generally recommended and is really an experimental
938fae3551SRodney W. Grimesfeature.
94a62dc406SDoug Rabson.It Fl I
95a62dc406SDoug RabsonSet the readdir read size to the specified value. The value should normally
96a62dc406SDoug Rabsonbe a multiple of DIRBLKSIZ that is <= the read size for the mount.
978fae3551SRodney W. Grimes.It Fl K
988fae3551SRodney W. GrimesPass Kerberos authenticators to the server for client-to-server
998fae3551SRodney W. Grimesuser-credential mapping.
100a62dc406SDoug RabsonThis requires that the kernel be built with the NFSKERB option.
101a62dc406SDoug Rabson(Refer to the INTERNET-DRAFT titled
102a62dc406SDoug Rabson.%T "Authentication Mechanisms for ONC RPC" ,
103a62dc406SDoug Rabsonfor more information.)
1048fae3551SRodney W. Grimes.It Fl L
1058fae3551SRodney W. GrimesUsed with NQNFS to set the lease term to the specified number of seconds.
1068fae3551SRodney W. GrimesOnly use this argument for mounts with a large round trip delay.
1078fae3551SRodney W. GrimesValues are normally in the 10-30 second range.
108cc75b131SJoerg Wunsch.It Fl N
109cc75b131SJoerg WunschDo
110cc75b131SJoerg Wunsch.Em not
111cc75b131SJoerg Wunschuse a reserved socket port number (see below).
1128fae3551SRodney W. Grimes.It Fl P
1138fae3551SRodney W. GrimesUse a reserved socket port number.
114cc75b131SJoerg WunschThis flag is obsolete, and only retained for compatibility reasons.
115cc75b131SJoerg WunschReserved port numbers are used by default now.
1168fae3551SRodney W. GrimesThis is useful for mounting servers that require clients to use a
117a62dc406SDoug Rabsonreserved port number on the mistaken belief that this makes NFS
118a62dc406SDoug Rabsonmore secure. (For the rare case where the client has a trusted root account
119e71057d8SMike Pritchardbut untrustworthy users and the network cables are in secure areas this does
120a62dc406SDoug Rabsonhelp, but for normal desktop clients this does not apply.)
1218fae3551SRodney W. Grimes.It Fl R
1228fae3551SRodney W. GrimesSet the retry count for doing the mount to the specified value.
1238fae3551SRodney W. Grimes.It Fl T
1248fae3551SRodney W. GrimesUse TCP transport instead of UDP.
1258fae3551SRodney W. GrimesThis is recommended for servers that are not on the same LAN cable as
1268fae3551SRodney W. Grimesthe client.
1278fae3551SRodney W. Grimes(NB: This is NOT supported by most non-BSD servers.)
128a62dc406SDoug Rabson.It Fl U
129a62dc406SDoug RabsonForce the mount protocol to use UDP transport, even for TCP NFS mounts.
130a62dc406SDoug Rabson(Necessary for some old BSD servers.)
1318fae3551SRodney W. Grimes.It Fl a
1328fae3551SRodney W. GrimesSet the read-ahead count to the specified value.
1338fae3551SRodney W. GrimesThis may be in the range of 0 - 4, and determines how many blocks
1348fae3551SRodney W. Grimeswill be read ahead when a large file is being read sequentially.
135a62dc406SDoug RabsonTrying a value greater than 1 for this is suggested for
136a62dc406SDoug Rabsonmounts with a large bandwidth * delay product.
1378fae3551SRodney W. Grimes.It Fl b
1388fae3551SRodney W. GrimesIf an initial attempt to contact the server fails, fork off a child to keep
1398fae3551SRodney W. Grimestrying the mount in the background.
1408fae3551SRodney W. GrimesUseful for
1418fae3551SRodney W. Grimes.Xr fstab 5 ,
1428fae3551SRodney W. Grimeswhere the filesystem mount is not critical to multiuser operation.
1438fae3551SRodney W. Grimes.It Fl c
1448fae3551SRodney W. GrimesFor UDP mount points, do not do a
1458fae3551SRodney W. Grimes.Xr connect 2 .
1468fae3551SRodney W. GrimesThis must be used for servers that do not reply to requests from the
147a62dc406SDoug Rabsonstandard NFS port number 2049.
1488fae3551SRodney W. Grimes.It Fl d
149a62dc406SDoug RabsonTurn off the dynamic retransmit timeout estimator.
150a62dc406SDoug RabsonThis may be useful for UDP mounts that exhibit high retry rates,
151a62dc406SDoug Rabsonsince it is possible that the dynamically estimated timeout interval is too
152a62dc406SDoug Rabsonshort.
1538fae3551SRodney W. Grimes.It Fl g
1548fae3551SRodney W. GrimesSet the maximum size of the group list for the credentials to the
1558fae3551SRodney W. Grimesspecified value.
1568fae3551SRodney W. GrimesThis should be used for mounts on old servers that cannot handle a
1578fae3551SRodney W. Grimesgroup list size of 16, as specified in RFC 1057.
1588fae3551SRodney W. GrimesTry 8, if users in a lot of groups cannot get response from the mount
1598fae3551SRodney W. Grimespoint.
1608fae3551SRodney W. Grimes.It Fl i
1618fae3551SRodney W. GrimesMake the mount interruptible, which implies that file system calls that
1628fae3551SRodney W. Grimesare delayed due to an unresponsive server will fail with EINTR when a
1638fae3551SRodney W. Grimestermination signal is posted for the process.
1648fae3551SRodney W. Grimes.It Fl l
165a62dc406SDoug RabsonUsed with NQNFS and NFSV3 to specify that the \fBReaddirPlus\fR RPC should
1668fae3551SRodney W. Grimesbe used.
1678fae3551SRodney W. GrimesThis option reduces RPC traffic for cases such as
1688fae3551SRodney W. Grimes.Dq "ls -l" ,
169a62dc406SDoug Rabsonbut tends to flood the attribute and name caches with prefetched entries.
170a62dc406SDoug RabsonTry this option and see whether performance improves or degrades. Probably
171a62dc406SDoug Rabsonmost useful for client to server network interconnects with a large bandwidth
172a62dc406SDoug Rabsontimes delay product.
1738fae3551SRodney W. Grimes.It Fl m
1748fae3551SRodney W. GrimesSet the Kerberos realm to the string argument.
1758fae3551SRodney W. GrimesUsed with the
1768fae3551SRodney W. Grimes.Fl K
1778fae3551SRodney W. Grimesoption for mounts to other realms.
1788fae3551SRodney W. Grimes.It Fl o
1798fae3551SRodney W. GrimesOptions are specified with a
1808fae3551SRodney W. Grimes.Fl o
1818fae3551SRodney W. Grimesflag followed by a comma separated string of options.
1828fae3551SRodney W. GrimesSee the
1838fae3551SRodney W. Grimes.Xr mount 8
1848fae3551SRodney W. Grimesman page for possible options and their meanings.
185bc2cfd71SKarl StricklandThe following NFS specific option is also available:
186bc2cfd71SKarl Strickland.Bl -tag -width indent
187bc2cfd71SKarl Strickland.It port=<port_number>
188bc2cfd71SKarl StricklandUse specified port number for NFS requests.
189bc2cfd71SKarl StricklandThe default is to query the portmapper for the NFS port.
190c92e3fa5SPeter Wemm.It acregmin=<seconds>
191c92e3fa5SPeter Wemm.It acregmax=<seconds>
192c92e3fa5SPeter Wemm.It acdirmin=<seconds>
193c92e3fa5SPeter Wemm.It acdirmax=<seconds>
194c92e3fa5SPeter WemmWhen attributes of files are cached, a timeout caclulated to determine
195c92e3fa5SPeter Wemmwhether a given cache entry has expired.  These four values determine the
196c92e3fa5SPeter Wemmupper and lower bounds of the timeouts for ``directory'' attributes and
197c92e3fa5SPeter Wemm``regular'' (ie: everything else).  The default values are 3 -> 60 seconds
198c92e3fa5SPeter Wemmfor regular files, and 30 -> 60 seconds for directories.  The algorithm to
199c92e3fa5SPeter Wemmcalculate the timeout is based on the age of the file.  The older the file,
200c92e3fa5SPeter Wemmthe longer the cache is considered valid, subject to the limits above.
201bc2cfd71SKarl Strickland.El
202f9dc1926SJoerg Wunsch.Pp
203f9dc1926SJoerg Wunsch.Bl -tag -width "dumbtimerXX"
204f9dc1926SJoerg Wunsch\fBHistoric \&-o options\fR
205f9dc1926SJoerg Wunsch.Pp
206f9dc1926SJoerg WunschUse of these options is deprecated, they are only mentioned here for
207f9dc1926SJoerg Wunschcompatibility with historic versions of
208f9dc1926SJoerg Wunsch.Nm mount_nfs .
209f9dc1926SJoerg Wunsch.It bg
210f9dc1926SJoerg WunschSame as
211f9dc1926SJoerg Wunsch.Fl b .
212f9dc1926SJoerg Wunsch.It conn
213f9dc1926SJoerg WunschSame as
214f9dc1926SJoerg Wunsch.Fl c .
215f9dc1926SJoerg Wunsch.It dumbtimer
216f9dc1926SJoerg WunschSame as
217f9dc1926SJoerg Wunsch.Fl d .
218f9dc1926SJoerg Wunsch.It intr
219f9dc1926SJoerg WunschSame as
220f9dc1926SJoerg Wunsch.Fl i .
221f9dc1926SJoerg Wunsch.It kerb
222f9dc1926SJoerg WunschSame as
223f9dc1926SJoerg Wunsch.Fl K .
2242cd1c32cSDoug Rabson.It nfsv2
2252cd1c32cSDoug RabsonSame as
2262cd1c32cSDoug Rabson.Fl 2 .
227f9dc1926SJoerg Wunsch.It nfsv3
228f9dc1926SJoerg WunschSame as
229f9dc1926SJoerg Wunsch.Fl 3 .
230f9dc1926SJoerg Wunsch.It rdirplus
231f9dc1926SJoerg WunschSame as
232f9dc1926SJoerg Wunsch.Fl l .
233f9dc1926SJoerg Wunsch.It mntudp
234f9dc1926SJoerg WunschSame as
235f9dc1926SJoerg Wunsch.Fl U .
236f9dc1926SJoerg Wunsch.It resvport
237f9dc1926SJoerg WunschSame as
238f9dc1926SJoerg Wunsch.Fl P .
239f9dc1926SJoerg Wunsch.It seqpacket
240f9dc1926SJoerg WunschSame as
241f9dc1926SJoerg Wunsch.Fl p .
242f9dc1926SJoerg Wunsch.It nqnfs
243f9dc1926SJoerg WunschSame as
244f9dc1926SJoerg Wunsch.Fl q .
245f9dc1926SJoerg Wunsch.It soft
246f9dc1926SJoerg WunschSame as
247f9dc1926SJoerg Wunsch.Fl s .
248f9dc1926SJoerg Wunsch.It tcp
249f9dc1926SJoerg WunschSame as
250f9dc1926SJoerg Wunsch.Fl T.
251f9dc1926SJoerg Wunsch.El
2528fae3551SRodney W. Grimes.It Fl q
2534a4c5285SPeter WemmUse the leasing extensions to the NFS Version 3 protocol
2544a4c5285SPeter Wemmto maintain cache consistency.
255a62dc406SDoug RabsonThis protocol Version 2, referred to as Not Quite Nfs (NQNFS),
256a62dc406SDoug Rabsonis only supported by this updated release of NFS code.
257a62dc406SDoug Rabson(It is not backwards compatible with the release of NQNFS that went out on
258a62dc406SDoug Rabson4.4BSD-Lite. To interoperate with a 4.4BSD-Lite NFS system you will have to
259e71057d8SMike Pritchardavoid this option until you have had an opportunity to upgrade the NFS code
260a62dc406SDoug Rabsonon all your 4.4BSD-Lite based systems.)
2618fae3551SRodney W. Grimes.It Fl r
2628fae3551SRodney W. GrimesSet the read data size to the specified value.
263a62dc406SDoug RabsonIt should normally be a power of 2 greater than or equal to 1024.
2648fae3551SRodney W. GrimesThis should be used for UDP mounts when the
2658fae3551SRodney W. Grimes.Dq "fragments dropped due to timeout"
2668fae3551SRodney W. Grimesvalue is getting large while actively using a mount point.
2678fae3551SRodney W. Grimes(Use
2688fae3551SRodney W. Grimes.Xr netstat 1
2698fae3551SRodney W. Grimeswith the
2708fae3551SRodney W. Grimes.Fl s
2718fae3551SRodney W. Grimesoption to see what the
2728fae3551SRodney W. Grimes.Dq "fragments dropped due to timeout"
2738fae3551SRodney W. Grimesvalue is.)
2748fae3551SRodney W. GrimesSee the
2758fae3551SRodney W. Grimes.Fl w
2768fae3551SRodney W. Grimesoption as well.
2778fae3551SRodney W. Grimes.It Fl s
2788fae3551SRodney W. GrimesA soft mount, which implies that file system calls will fail
2798fae3551SRodney W. Grimesafter \fBRetry\fR round trip timeout intervals.
2808fae3551SRodney W. Grimes.It Fl t
2818fae3551SRodney W. GrimesSet the initial retransmit timeout to the specified value.
2828fae3551SRodney W. GrimesMay be useful for fine tuning UDP mounts over internetworks
2838fae3551SRodney W. Grimeswith high packet loss rates or an overloaded server.
2848fae3551SRodney W. GrimesTry increasing the interval if
2858fae3551SRodney W. Grimes.Xr nfsstat 1
2868fae3551SRodney W. Grimesshows high retransmit rates while the file system is active or reducing the
2878fae3551SRodney W. Grimesvalue if there is a low retransmit rate but long response delay observed.
288a62dc406SDoug Rabson(Normally, the -d option should be specified when using this option to manually
289a62dc406SDoug Rabsontune the timeout
290a62dc406SDoug Rabsoninterval.)
2918fae3551SRodney W. Grimes.It Fl w
2928fae3551SRodney W. GrimesSet the write data size to the specified value.
2938fae3551SRodney W. GrimesDitto the comments w.r.t. the
2948fae3551SRodney W. Grimes.Fl r
2958fae3551SRodney W. Grimesoption, but using the
2968fae3551SRodney W. Grimes.Dq "fragments dropped due to timeout"
2978fae3551SRodney W. Grimesvalue on the server instead of the client.
2988fae3551SRodney W. GrimesNote that both the
2998fae3551SRodney W. Grimes.Fl r
3008fae3551SRodney W. Grimesand
3018fae3551SRodney W. Grimes.Fl w
3028fae3551SRodney W. Grimesoptions should only be used as a last ditch effort at improving performance
3038fae3551SRodney W. Grimeswhen mounting servers that do not support TCP mounts.
3048fae3551SRodney W. Grimes.It Fl x
3058fae3551SRodney W. GrimesSet the retransmit timeout count for soft mounts to the specified value.
3068fae3551SRodney W. Grimes.El
3078fae3551SRodney W. Grimes.Sh SEE ALSO
3088fae3551SRodney W. Grimes.Xr mount 2 ,
3098fae3551SRodney W. Grimes.Xr unmount 2 ,
3108fae3551SRodney W. Grimes.Xr fstab 5 ,
3118fae3551SRodney W. Grimes.Xr mount 8
3128fae3551SRodney W. Grimes.Sh BUGS
3138fae3551SRodney W. GrimesDue to the way that Sun RPC is implemented on top of UDP (unreliable datagram)
3148fae3551SRodney W. Grimestransport, tuning such mounts is really a black art that can only be expected
3158fae3551SRodney W. Grimesto have limited success.
3168fae3551SRodney W. GrimesFor clients mounting servers that are not on the same
3178fae3551SRodney W. GrimesLAN cable or that tend to be overloaded,
3188fae3551SRodney W. GrimesTCP transport is strongly recommended,
3198fae3551SRodney W. Grimesbut unfortunately this is restricted to mostly 4.4BSD servers.
320