7c7e2af6da
- Remove Tn macros - Refernce sysctl(8) instead of sysctl(1) - Start new sentences on new lines - Capitalize NFS where needed - Use Fx for FreeBSD - Remove a list block (Bl) that was added to the manual page by accident in r335174 Reviewed by: bcr Approved by: doc (bcr) Differential Revision: https://reviews.freebsd.org/D20215
336 lines
9.9 KiB
Groff
336 lines
9.9 KiB
Groff
.\" Copyright (c) 1989, 1991, 1993
|
|
.\" 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. 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.
|
|
.\"
|
|
.\" @(#)nfsd.8 8.4 (Berkeley) 3/29/95
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd February 14, 2019
|
|
.Dt NFSD 8
|
|
.Os
|
|
.Sh NAME
|
|
.Nm nfsd
|
|
.Nd remote
|
|
NFS server
|
|
.Sh SYNOPSIS
|
|
.Nm
|
|
.Op Fl ardute
|
|
.Op Fl n Ar num_servers
|
|
.Op Fl h Ar bindip
|
|
.Op Fl p Ar pnfs_setup
|
|
.Op Fl m Ar mirror_level
|
|
.Op Fl V Ar virtual_hostname
|
|
.Op Fl Fl maxthreads Ar max_threads
|
|
.Op Fl Fl minthreads Ar min_threads
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
utility runs on a server machine to service NFS requests from client machines.
|
|
At least one
|
|
.Nm
|
|
must be running for a machine to operate as a server.
|
|
.Pp
|
|
Unless otherwise specified, eight servers per CPU for UDP transport are
|
|
started.
|
|
.Pp
|
|
The following options are available:
|
|
.Bl -tag -width Ds
|
|
.It Fl r
|
|
Register the NFS service with
|
|
.Xr rpcbind 8
|
|
without creating any servers.
|
|
This option can be used along with the
|
|
.Fl u
|
|
or
|
|
.Fl t
|
|
options to re-register NFS if the rpcbind server is restarted.
|
|
.It Fl d
|
|
Unregister the NFS service with
|
|
.Xr rpcbind 8
|
|
without creating any servers.
|
|
.It Fl V Ar virtual_hostname
|
|
Specifies a hostname to be used as a principal name, instead of
|
|
the default hostname.
|
|
.It Fl n Ar threads
|
|
Specifies how many servers to create.
|
|
This option is equivalent to specifying
|
|
.Fl Fl maxthreads
|
|
and
|
|
.Fl Fl minthreads
|
|
with their respective arguments to
|
|
.Ar threads .
|
|
.It Fl Fl maxthreads Ar threads
|
|
Specifies the maximum servers that will be kept around to service requests.
|
|
.It Fl Fl minthreads Ar threads
|
|
Specifies the minimum servers that will be kept around to service requests.
|
|
.It Fl h Ar bindip
|
|
Specifies which IP address or hostname to bind to on the local host.
|
|
This option is recommended when a host has multiple interfaces.
|
|
Multiple
|
|
.Fl h
|
|
options may be specified.
|
|
.It Fl a
|
|
Specifies that nfsd should bind to the wildcard IP address.
|
|
This is the default if no
|
|
.Fl h
|
|
options are given.
|
|
It may also be specified in addition to any
|
|
.Fl h
|
|
options given.
|
|
Note that NFS/UDP does not operate properly when
|
|
bound to the wildcard IP address whether you use -a or do not use -h.
|
|
.It Fl p Ar pnfs_setup
|
|
Enables pNFS support in the server and specifies the information that the
|
|
daemon needs to start it.
|
|
This option can only be used on one server and specifies that this server
|
|
will be the MetaData Server (MDS) for the pNFS service.
|
|
This can only be done if there is at least one
|
|
.Fx
|
|
system configured
|
|
as a Data Server (DS) for it to use.
|
|
.Pp
|
|
The
|
|
.Ar pnfs_setup
|
|
string is a set of fields separated by ',' characters:
|
|
Each of these fields specifies one DS.
|
|
It consists of a server hostname, followed by a ':'
|
|
and the directory path where the DS's data storage file system is mounted on
|
|
this MDS server.
|
|
This can optionally be followed by a '#' and the mds_path, which is the
|
|
directory path for an exported file system on this MDS.
|
|
If this is specified, it means that this DS is to be used to store data
|
|
files for this mds_path file system only.
|
|
If this optional component does not exist, the DS will be used to store data
|
|
files for all exported MDS file systems.
|
|
The DS storage file systems must be mounted on this system before the
|
|
.Nm
|
|
is started with this option specified.
|
|
.br
|
|
For example:
|
|
.sp
|
|
nfsv4-data0:/data0,nfsv4-data1:/data1
|
|
.sp
|
|
would specify two DS servers called nfsv4-data0 and nfsv4-data1 that comprise
|
|
the data storage component of the pNFS service.
|
|
These two DSs would be used to store data files for all exported file systems
|
|
on this MDS.
|
|
The directories
|
|
.Dq /data0
|
|
and
|
|
.Dq /data1
|
|
are where the data storage servers exported
|
|
storage directories are mounted on this system (which will act as the MDS).
|
|
.br
|
|
Whereas, for the example:
|
|
.sp
|
|
nfsv4-data0:/data0#/export1,nfsv4-data1:/data1#/export2
|
|
.sp
|
|
would specify two DSs as above, however nfsv4-data0 will be used to store
|
|
data files for
|
|
.Dq /export1
|
|
and nfsv4-data1 will be used to store data files for
|
|
.Dq /export2 .
|
|
.sp
|
|
When using IPv6 addresses for DSs
|
|
be wary of using link local addresses.
|
|
The IPv6 address for the DS is sent to the client and there is no scope
|
|
zone in it.
|
|
As such, a link local address may not work for a pNFS client to DS
|
|
TCP connection.
|
|
When parsed,
|
|
.Nm
|
|
will only use a link local address if it is the only address returned by
|
|
.Xr getaddrinfo 3
|
|
for the DS hostname.
|
|
.It Fl m Ar mirror_level
|
|
This option is only meaningful when used with the
|
|
.Fl p
|
|
option.
|
|
It specifies the
|
|
.Dq mirror_level ,
|
|
which defines how many of the DSs will
|
|
have a copy of a file's data storage file.
|
|
The default of one implies no mirroring of data storage files on the DSs.
|
|
The
|
|
.Dq mirror_level
|
|
would normally be set to 2 to enable mirroring, but
|
|
can be as high as NFSDEV_MAXMIRRORS.
|
|
There must be at least
|
|
.Dq mirror_level
|
|
DSs for each exported file system on the MDS, as specified in the
|
|
.Fl p
|
|
option.
|
|
This implies that, for the above example using "#/export1" and "#/export2",
|
|
mirroring cannot be done.
|
|
There would need to be two DS entries for each of "#/export1" and "#/export2"
|
|
in order to support a
|
|
.Dq mirror_level
|
|
of two.
|
|
.Pp
|
|
If mirroring is enabled, the server must use the Flexible File
|
|
layout.
|
|
If mirroring is not enabled, the server will use the File layout
|
|
by default, but this default can be changed to the Flexible File layout if the
|
|
.Xr sysctl 8
|
|
vfs.nfsd.default_flexfile
|
|
is set non-zero.
|
|
.It Fl t
|
|
Serve TCP NFS clients.
|
|
.It Fl u
|
|
Serve UDP NFS clients.
|
|
.It Fl e
|
|
Ignored; included for backward compatibility.
|
|
.El
|
|
.Pp
|
|
For example,
|
|
.Dq Li "nfsd -u -t -n 6"
|
|
serves UDP and TCP transports using six daemons.
|
|
.Pp
|
|
A server should run enough daemons to handle
|
|
the maximum level of concurrency from its clients,
|
|
typically four to six.
|
|
.Pp
|
|
The
|
|
.Nm
|
|
utility listens for service requests at the port indicated in the
|
|
NFS server specification; see
|
|
.%T "Network File System Protocol Specification" ,
|
|
RFC1094,
|
|
.%T "NFS: Network File System Version 3 Protocol Specification" ,
|
|
RFC1813,
|
|
.%T "Network File System (NFS) Version 4 Protocol" ,
|
|
RFC3530 and
|
|
.%T "Network File System (NFS) Version 4 Minor Version 1 Protocol" ,
|
|
RFC5661.
|
|
.Pp
|
|
If
|
|
.Nm
|
|
detects that
|
|
NFS is not loaded in the running kernel, it will attempt
|
|
to load a loadable kernel module containing NFS support using
|
|
.Xr kldload 2 .
|
|
If this fails, or no NFS KLD is available,
|
|
.Nm
|
|
will exit with an error.
|
|
.Pp
|
|
If
|
|
.Nm
|
|
is to be run on a host with multiple interfaces or interface aliases, use
|
|
of the
|
|
.Fl h
|
|
option is recommended.
|
|
If you do not use the option NFS may not respond to
|
|
UDP packets from the same IP address they were sent to.
|
|
Use of this option
|
|
is also recommended when securing NFS exports on a firewalling machine such
|
|
that the NFS sockets can only be accessed by the inside interface.
|
|
The
|
|
.Nm ipfw
|
|
utility
|
|
would then be used to block NFS-related packets that come in on the outside
|
|
interface.
|
|
.Pp
|
|
If the server has stopped servicing clients and has generated a console message
|
|
like
|
|
.Dq Li "nfsd server cache flooded..." ,
|
|
the value for vfs.nfsd.tcphighwater needs to be increased.
|
|
This should allow the server to again handle requests without a reboot.
|
|
Also, you may want to consider decreasing the value for
|
|
vfs.nfsd.tcpcachetimeo to several minutes (in seconds) instead of 12 hours
|
|
when this occurs.
|
|
.Pp
|
|
Unfortunately making vfs.nfsd.tcphighwater too large can result in the mbuf
|
|
limit being reached, as indicated by a console message
|
|
like
|
|
.Dq Li "kern.ipc.nmbufs limit reached" .
|
|
If you cannot find values of the above
|
|
.Nm sysctl
|
|
values that work, you can disable the DRC cache for TCP by setting
|
|
vfs.nfsd.cachetcp to 0.
|
|
.Pp
|
|
The
|
|
.Nm
|
|
utility has to be terminated with
|
|
.Dv SIGUSR1
|
|
and cannot be killed with
|
|
.Dv SIGTERM
|
|
or
|
|
.Dv SIGQUIT .
|
|
The
|
|
.Nm
|
|
utility needs to ignore these signals in order to stay alive as long
|
|
as possible during a shutdown, otherwise loopback mounts will
|
|
not be able to unmount.
|
|
If you have to kill
|
|
.Nm
|
|
just do a
|
|
.Dq Li "kill -USR1 <PID of master nfsd>"
|
|
.Sh EXIT STATUS
|
|
.Ex -std
|
|
.Sh SEE ALSO
|
|
.Xr nfsstat 1 ,
|
|
.Xr kldload 2 ,
|
|
.Xr nfssvc 2 ,
|
|
.Xr nfsv4 4 ,
|
|
.Xr pnfs 4 ,
|
|
.Xr pnfsserver 4 ,
|
|
.Xr exports 5 ,
|
|
.Xr stablerestart 5 ,
|
|
.Xr gssd 8 ,
|
|
.Xr ipfw 8 ,
|
|
.Xr mountd 8 ,
|
|
.Xr nfsiod 8 ,
|
|
.Xr nfsrevoke 8 ,
|
|
.Xr nfsuserd 8 ,
|
|
.Xr rpcbind 8
|
|
.Sh HISTORY
|
|
The
|
|
.Nm
|
|
utility first appeared in
|
|
.Bx 4.4 .
|
|
.Sh BUGS
|
|
If
|
|
.Nm
|
|
is started when
|
|
.Xr gssd 8
|
|
is not running, it will service AUTH_SYS requests only.
|
|
To fix the problem you must kill
|
|
.Nm
|
|
and then restart it, after the
|
|
.Xr gssd 8
|
|
is running.
|
|
.Pp
|
|
If mirroring is enabled via the
|
|
.Fl m
|
|
option and there are Linux clients doing NFSv4.1 mounts, those clients
|
|
need to be patched to support the
|
|
.Dq tightly coupled
|
|
variant of
|
|
the Flexible File layout or the
|
|
.Xr sysctl 8
|
|
vfs.nfsd.flexlinuxhack
|
|
must be set to one on the MDS as a workaround.
|