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diff --git a/sbin/mount_nfs/mount_nfs.8 b/sbin/mount_nfs/mount_nfs.8 new file mode 100644 index 000000000000..decac6efefed --- /dev/null +++ b/sbin/mount_nfs/mount_nfs.8 @@ -0,0 +1,222 @@ +.\" Copyright (c) 1992, 1993, 1994 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)mount_nfs.8 8.2 (Berkeley) 3/27/94 +.\" +.Dd March 27, 1994 +.Dt MOUNT_NFS 8 +.Os BSD 4.4 +.Sh NAME +.Nm mount_nfs +.Nd mount nfs file systems +.Sh SYNOPSIS +.Nm mount_nfs +.Op Fl KMPTbcdiklqs +.Op Fl D Ar deadthresh +.Op Fl L Ar leaseterm +.Op Fl R Ar retrycnt +.Op Fl a Ar maxreadahead +.Op Fl g Ar maxgroups +.Op Fl m Ar realm +.Op Fl o Ar options +.Op Fl r Ar readsize +.Op Fl t Ar timeout +.Op Fl w Ar writesize +.Op Fl x Ar retrans +.Ar rhost:path node +.Sh DESCRIPTION +The +.Nm mount_nfs +command +calls the +.Xr mount 2 +system call to prepare and graft a remote nfs file system (rhost:path) +on to the file system tree at the point +.Ar node. +This command is normally executed by +.Xr mount 8 . +It implements the mount protocol as described in RFC 1094, Appendix A. +.Pp +The options are: +.Bl -tag -width indent +.It Fl D +Used with NQNFS to set the +.Dq "dead server threshold" +to the specified number of round trip timeout intervals. +After a +.Dq "dead server threshold" +of retransmit timeouts, +cached data for the unresponsive server is assumed to still be valid. +Values may be set in the range of 1 - 9, with 9 referring to an +.Dq "infinite dead threshold" +(i.e. never assume cached data still valid). +This option is not generally recommended and is really an experimental +feature. +.It Fl K +Pass Kerberos authenticators to the server for client-to-server +user-credential mapping. +This may only be used over TCP mounts between 4.4BSD clients and servers. +.It Fl L +Used with NQNFS to set the lease term to the specified number of seconds. +Only use this argument for mounts with a large round trip delay. +Values are normally in the 10-30 second range. +.It Fl M +Assume that other clients are not writing a file concurrently with this client. +This implements a slightly less strict consistency criteria than 4.3BSD-Reno +did, that is more in line with most commercial client implementations. +This is recommended for servers that do not support leasing. +.It Fl P +Use a reserved socket port number. +This is useful for mounting servers that require clients to use a +reserved port number. +.It Fl R +Set the retry count for doing the mount to the specified value. +.It Fl T +Use TCP transport instead of UDP. +This is recommended for servers that are not on the same LAN cable as +the client. +(NB: This is NOT supported by most non-BSD servers.) +.It Fl a +Set the read-ahead count to the specified value. +This may be in the range of 0 - 4, and determines how many blocks +will be read ahead when a large file is being read sequentially. +This is recommended for mounts with a large bandwidth * delay product. +.It Fl b +If an initial attempt to contact the server fails, fork off a child to keep +trying the mount in the background. +Useful for +.Xr fstab 5 , +where the filesystem mount is not critical to multiuser operation. +.It Fl c +For UDP mount points, do not do a +.Xr connect 2 . +This must be used for servers that do not reply to requests from the +standard port number. +.It Fl d +Do not estimate retransmit timeout dynamically. +This may be useful for UDP mounts that exhibit high retry rates. +.It Fl g +Set the maximum size of the group list for the credentials to the +specified value. +This should be used for mounts on old servers that cannot handle a +group list size of 16, as specified in RFC 1057. +Try 8, if users in a lot of groups cannot get response from the mount +point. +.It Fl i +Make the mount interruptible, which implies that file system calls that +are delayed due to an unresponsive server will fail with EINTR when a +termination signal is posted for the process. +.It Fl k +Used with NQNFS to specify +.Dq get a lease +for the file name being looked up. +This is recommended unless the server is complaining about excessive +lease load. +.It Fl l +Used with NQNFS to specify that the \fBReaddir_and_Lookup\fR RPC should +be used. +This option reduces RPC traffic for cases such as +.Dq "ls -l" , +but increases the lease load on the server. +This is recommended unless the server is complaining about excessive +lease load. +.It Fl m +Set the Kerberos realm to the string argument. +Used with the +.Fl K +option for mounts to other realms. +.It Fl o +Options are specified with a +.Fl o +flag followed by a comma separated string of options. +See the +.Xr mount 8 +man page for possible options and their meanings. +.It Fl q +Use the leasing extensions to the protocol to maintain cache consistency. +This protocol, referred to as Not Quite Nfs (NQNFS), +is only supported by 4.4BSD servers. +.It Fl r +Set the read data size to the specified value. +It should be a power of 2 greater than or equal to 1024. +This should be used for UDP mounts when the +.Dq "fragments dropped due to timeout" +value is getting large while actively using a mount point. +(Use +.Xr netstat 1 +with the +.Fl s +option to see what the +.Dq "fragments dropped due to timeout" +value is.) +See the +.Fl w +option as well. +.It Fl s +A soft mount, which implies that file system calls will fail +after \fBRetry\fR round trip timeout intervals. +.It Fl t +Set the initial retransmit timeout to the specified value. +May be useful for fine tuning UDP mounts over internetworks +with high packet loss rates or an overloaded server. +Try increasing the interval if +.Xr nfsstat 1 +shows high retransmit rates while the file system is active or reducing the +value if there is a low retransmit rate but long response delay observed. +.It Fl w +Set the write data size to the specified value. +Ditto the comments w.r.t. the +.Fl r +option, but using the +.Dq "fragments dropped due to timeout" +value on the server instead of the client. +Note that both the +.Fl r +and +.Fl w +options should only be used as a last ditch effort at improving performance +when mounting servers that do not support TCP mounts. +.It Fl x +Set the retransmit timeout count for soft mounts to the specified value. +.El +.Sh SEE ALSO +.Xr mount 2 , +.Xr unmount 2 , +.Xr fstab 5 , +.Xr mount 8 +.Sh BUGS +Due to the way that Sun RPC is implemented on top of UDP (unreliable datagram) +transport, tuning such mounts is really a black art that can only be expected +to have limited success. +For clients mounting servers that are not on the same +LAN cable or that tend to be overloaded, +TCP transport is strongly recommended, +but unfortunately this is restricted to mostly 4.4BSD servers. |